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Science Study Notes 2011 Andrew Newbound © Andrew Newbound 2013
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Definitions Universe Big Bang Steady state Cosmology
Huge space which contains all of the mater and energy in existence Big Bang Theory that universe started in a big explosion from a single point Steady state Theory that universe has always existed and matter is being created all the time Cosmology Scientific study of theories about history & future of universe © Andrew Newbound 2013
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Definitions Evidence Organisms Darwin Evolution
Something that helps you form a conclusion Organisms Living things Darwin Created the theory of evolution and explained it through the mechanism of natural selection Evolution Slow change in a population of living things over many generations © Andrew Newbound 2013
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Definitions Comparative anatomy Fossils Geographical Isolation
Study of similarities and differences in body structures Fossils Remains/impressions of living things, mostly found in rock Geographical Isolation Natural arrangements of plants and animals in particular regions Homo sapiens Scientific term form modern humans © Andrew Newbound 2013
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Definitions Lamarck Natural Selection Hominid
Suggested that evolution was caused by organisms acquiring variations as they lived their lives, that were then inherited by their offspring. Natural Selection When only organism best adapted to their environment will survive and transmit their genes to their offspring Hominid Early human-like fossils that walked upright on 2 legs and were more like humans than apes © Andrew Newbound 2013
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The Big Bang 1929 1933 1948 Edwin Hubble Red Shift Big Bang Theory
Steady state theory © Andrew Newbound 2013
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The Big Bang 1965 1992 Robert Wilson & Arno ]]
Discovered microwave radiation in the universe 1992 COBE (Cosmic Background Radiation Explorer) © Andrew Newbound 2013
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The Big Bang Astronomer Cosmologist Astronomers & Cosmologists
Studies objects in space & info that can be derived from them Cosmologist Studies theories about the universe Formation, history & future of universe Astronomers & Cosmologists Use telescopes + satellites + space probes Computer simulations & models Big Bang Before = nothing Started space, energy & time © Andrew Newbound 2013
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The Big Bang Origin of Universe Theory For Against Big Bang
Microwave energy detected from Big Bang (background radiation) Red shift (universe expanding) Ripples in universe Starting point Steady state Starting point explained Galaxies can’t be made of nothing © Andrew Newbound 2013
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The Big Crunch Universe runs out of energy Stops expanding
Universe shrinks Back to size of Big Bang © Andrew Newbound 2013
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The Beginnings of Life 1924 1953 Aleksanr Oparin
Life originated in pools of water 1953 Stanley Miller Showed how earth could have started Wrong quantities of gases Fred Hoyle Life originated in space Molecules that make up life – on comets & dust of nebulae © Andrew Newbound 2013
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The Beginnings of Life 1969 1997 September
Meteorite flashed across sky in Victoria 4600 million years old 1997 ALH84001 Confirmed come from mars Microscopic patterns similar to bacteria colonies © Andrew Newbound 2013
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The Beginnings of Life Bacteria sent into space
Spacecraft ‘STARDUST’ collected samples from Comet Wild 2 in Jan 2004 Evidence for life on earth Fossils Oldest = bacteria Use hydrogen sulphide as an energy source Bacteria in harsh conditions Archaea © Andrew Newbound 2013
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The Beginnings of Life Planetary scientists Mars
Bacteria that can live in other places in the solar system Mars Most probable planet to support life Evidence for water has been detected Best place to find bacterial life Moon surrounding Jupitor/Saturn © Andrew Newbound 2013
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Charles Darwin Born: England 1809 Loved nature studies
Large collection of beetles Sorted them Catalogued the varieties of pigeons Studied to be a doctor Left when witnessed a child in surgery Screaming with pain © Andrew Newbound 2013
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Charles Darwin Heard father & grandfather talk about evolution
Unpaid naturalist on voyage around world Survey parts of world Draw biological specimens + descriptions of them South America Large fossil bones of extinct animals Resembled bones in living animals © Andrew Newbound 2013
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Charles Darwin After earthquake Galapagos island finches
Mussels moved to 3m above high tide mark Showed environments change Galapagos island finches Each had different: Shaped beak Source of food Similar to each other Like once same type of bird © Andrew Newbound 2013
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Charles Darwin Beetles Pigeons Finches Findings
Small differences between living things are important Pigeons Living things change over time Finches Populations change over time and grow apart when separated Findings Reluctant to publish Alfred Russel Wallace had same findings Darwin’s theory publicised & well known © Andrew Newbound 2013
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Comparative Anatomy Study of similarities & differences in body structures Similarities Determine evolutionary relationships Limb adapted by evolution for use in different environments © Andrew Newbound 2013
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Comparative Embryology
Study of embryos All similar during early development © Andrew Newbound 2013
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Evidence for Evolution
Comparative anatomy Some bones can be used for different purposes Pentadacyl limb Bones that are not used may still be around Comparative embryology Common ancestors changed to form different species Split further along than embryos Comparative DNA sequencing Measuring how long ago 2 species were 1 species Similarities compared Humans & chimpanzees 5-6 million years ago (98% similar) © Andrew Newbound 2013
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Evidence for Evolution
Fossils Minerals replaced by carbonates Impressions/casts Chemicals can’t break down Horse evolution using fossils Come from N. America Had 4 digits per limb Changed to graze tough grasses 3rd digit’s nail = hoof © Andrew Newbound 2013
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Evidence for Evolution
Dating Fossils Position in layers of rock Law of superposition Potasium10 Argon40 Older fossils up to 1,000,000 years ago Measure amounts of argon Carbon14 dating Ratio of carbon14 to carbon12 50,000 years ago © Andrew Newbound 2013
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Evidence for Evolution
Bio-Geographical Distribution Ratites (flightless birds all related) Emu, Kiwi etc. Continental drift © Andrew Newbound 2013
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Genetic sources All organisms contain chemicals that are based primarily on carbon DNA Structural and chemical similarities between things suggest relationships © Andrew Newbound 2013
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Palaeontology Study of fossils
Evidence of evolution because oldest fossils are simples animals & plants As rocks get younger the fossils get more complex © Andrew Newbound 2013
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Geographical Distribution of Related Species
Australia has its own distinctive kinds of living things E.g. waratah Endemic to Australia Explanations Begin as inferences Make hypothesis Produce theories Best scientific explanation at the time for the available evidence © Andrew Newbound 2013
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Dating Fossils Carbon Dating = Absolute Dating Relative dating
1000s of years ago Relative dating Only tell whether fossil is older or younger Layer of rock found in © Andrew Newbound 2013
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Natural Selection Artificial selection Slight advantage Slow
Farmers selecting largest/strongest animals for breeding Slight advantage More likely to survive Natural selection Slow Many generations E.g. Insect resistance to pesticides © Andrew Newbound 2013
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Lamarck's theory Use it or lose it Acquired characteristics WRONG
© Andrew Newbound 2013
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Darwin’s Theory Survival of the fittest
All individuals have different characteristics (variations) All individuals struggle to survive Find food, shelter and mates Avoid danger Some individuals born with variations help to survive Survive best and reproduce to pass successful variations onto offspring Population changes so that it has characteristics that make it best suited to the environment © Andrew Newbound 2013
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In The Beginning Hominids Pre-hominids
Closer to humans than apes Pre-hominids Closer to apes than humans Humans different to other animals Large brain for reasoning & language Opposable thumb Incomplete fossil records of human evolution © Andrew Newbound 2013
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In the Beginning © Andrew Newbound 2013 Austalopithecus Homo habilis
Homo erectus Neanderthals Cro-Magnon man Homo Sapien © Andrew Newbound 2013
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In The Beginning Hominid fossil changes Neanderthals & Cro Magnons
Brains grew Face became vertical Brow ridges rose Teeth shrunk Neanderthals & Cro Magnons Lived in caves Shelter & protection Preserved from elements Lots of fossils Super species Able to destroy all other living things on earth © Andrew Newbound 2013
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Gripped By Gravity (Motion)
Topic 2 © Andrew Newbound 2013
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Glossary Mass Weight Force Acceleration Net Force
The amount of matter in something Weight The force of gravity pulling on a mass Force A push, pull or twist applied to an object Acceleration The rate at which an object changes its speed Net Force The directional sum of all forces acting on an object © Andrew Newbound 2013
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Glossary Friction Distance Speed Time Average Speed
A rubbing force that slows moving objects Distance How far it is between 2 points Speed How quickly an object is moving Time How long it takes between 2 events Average Speed The total distance travelled divided by the total time taken © Andrew Newbound 2013
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Glossary Velocity Ticker timer Inertia Momentum Newton’s laws
Speed in a given direction Ticker timer A device that produces a series of dots on paper Inertia The tendency of an object to stay still or keep moving Momentum The product of mass and velocity Newton’s laws The 3 laws proposed by Sir Isaac Newton that describe motion © Andrew Newbound 2013
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Speed Formula 𝑆= 𝐷 𝑇 © Andrew Newbound 2013
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Measuring Motion Distance Time Speed
Measured with tape measure/trundle wheel Trundle wheel circumference = 1m Time Measured in seconds (s), minutes (min), hours (h), days and weeks Usually measured in s for experiments Speed In car, measured in km/h In lab, measured in m/s (𝑚/ 𝑠 −1 ) © Andrew Newbound 2013
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Measuring Motion Velocity Instantaneous speed Average Speed
Important for ships at sea etc. Instantaneous speed Speed the moment you look at it Measured: Speedometer, laser/radar speed gun Average Speed Speed if same speed constantly over journey Average speed velocity, instantaneous velocity Same as speed but with distance also © Andrew Newbound 2013
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Measuring Motion ×3.6 m/s km/h ÷3.6 © Andrew Newbound 2013
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Velocity If go back to start, average velocity is 0
© Andrew Newbound 2013
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Distance/time Graphs Gradient tells speed Time along bottom
Steeper = faster Flat = 0 (object not moving) Straight line = speed not changing Time along bottom Distance along side Scale must be constant © Andrew Newbound 2013
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© Andrew Newbound 2013
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Measuring Speed Easier studied if broken down Ticker timer
Measure time taken to walk along segments of path Constant speed = same distance in same time Ticker timer Measure time and distance together Hits carbon paper at regular intervals Dots close together = slow speed Dots consistently spaced = consistent speed Moving apart = accelerating Need to know distance & time between dots Time = 0.02s ( 1 50 𝑠) 1 dimension (forward & backward) © Andrew Newbound 2013
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Measuring Speed Use video camera Flashing light
Use pause button on VCR to analyse motion If picture contains ruler + clock Flashing light Disco – motion appears jerky Photographed = multiple images of moving dancers Stroboscopic light Flashes at regular intervals Multiple images of moving object Multiflash photography Movement in 2 dimensions (up & down, left & right) © Andrew Newbound 2013
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Calculating Speed Using Ticker Tape
Distance from start to finish = cm = m Number of gaps between dots = 1 50 × number of dots = s Speed = 𝐷 𝑇 = / = m/s © Andrew Newbound 2013
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Calculating Speed Using Ticker Tape
Distance from start to finish =9.5 cm =0.095m Number of gaps between dots =7 1 50 × number of dots =0.14s Speed = 𝐷 𝑇 =0.095/0.14 =0.68m/s © Andrew Newbound 2013
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Distance – Time Graphs Vertical axis = distance Horizontal axis = time
Straight line sloping upwards Motion at a constant speed Horizontal dine Stationary object w/ no motion Zero speed At rest Curved line sloping upwards Acceleration © Andrew Newbound 2013
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𝑉𝑒𝑙𝑜𝑐𝑖𝑡𝑦= 𝑑𝑖𝑠𝑝𝑙𝑎𝑐𝑒𝑚𝑒𝑛𝑡 𝑡𝑖𝑚𝑒
Acceleration 𝑉𝑒𝑙𝑜𝑐𝑖𝑡𝑦= 𝑑𝑖𝑠𝑝𝑙𝑎𝑐𝑒𝑚𝑒𝑛𝑡 𝑡𝑖𝑚𝑒 𝑎𝑣 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛= 𝑐ℎ𝑎𝑛𝑒 𝑖𝑛 𝑠𝑝𝑒𝑒𝑑 time 𝑎𝑣 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛= 𝑓𝑖𝑛𝑎𝑙 𝑠𝑝𝑒𝑒𝑑−starting speed time © Andrew Newbound 2013
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Acceleration If a car can go from 0km/h to 60km/h in 6s, what is its acceleration? = 60−0 𝑘𝑚/ℎ 6𝑠 = 60𝑘𝑚/ℎ 6𝑠 =10𝑘𝑚/ℎ/𝑠 © Andrew Newbound 2013
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Speed/Time Graphs Shows acceleration Horizontal = constant speed
Slope of graph Horizontal = constant speed Down = decelerating Up = accelerating © Andrew Newbound 2013
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© Andrew Newbound 2013
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Gravity & Acceleration
Change in motion over time Circular motion Changing direction but not speed Still accelerated Increase in speed Deceleration Decrease in speed © Andrew Newbound 2013
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Gravity & Acceleration
Jump from aeroplane Keep accelerating until hit terminal velocity Due to air resistance Car stopping at traffic lights Decelerates until hits 0 speed Satellite orbiting earth Constant speed but accelerating due to change in direction Weightlessness No gravity E.g. being in space © Andrew Newbound 2013
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Gravity & Acceleration
Jumping = better on moon Running = better on earth Acceleration = 𝑚/ 𝑠 2 𝑆𝑝𝑒𝑒𝑑 𝑚/𝑠 𝑇𝑖𝑚𝑒 (𝑠) ⇒ 𝑚 𝑠 𝑠 ⇒ 𝑚 𝑠𝑠 ⇒ 𝑚 𝑠 2 ⇒𝑚/ 𝑠 2 OR 𝑚 𝑠 −2 © Andrew Newbound 2013
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Chapter Review Speed Acceleration Data Graph Ticker timer
How fast something is moving Acceleration Going faster, slower or changing direction Data Information in numerical form Graph Visual way of displaying data Ticker timer Leaves dot on a paper tape to record motion © Andrew Newbound 2013
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Chapter Review Velocity Circular Motion Harmonic Pendulum Weight
Speed in a given direction Circular Motion Motion of an object round and round Harmonic Motion of an object going to and fro Pendulum Swinging object that can be used to measure time Weight Downwards force due to gravitational acceleration © Andrew Newbound 2013
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Chapter Review Gravity affects objects at the same rate
Heavy stone, light stone fall at same time Moon’s gravity < earth’s gravity Can jump higher Gravity causes objects to accelerate towards earth Air resistance slows falling objects near earth Terminal velocity Constant speed Same time to travel same distance © Andrew Newbound 2013
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Chapter Review Gravity is constant with/without air Higher speed
Objects would fall faster due to no terminal velocity Higher speed Shorter time to travel same distance Fall faster & faster if jump from plane Until hit terminal velocity Average speed 𝑚 𝑠 ×3.6=𝑘𝑚/ℎ © Andrew Newbound 2013
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Ticker Timer Closer together = slower speed
Farther apart = faster speed Moving apart = accelerating Moving together = decelerating © Andrew Newbound 2013
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Pushes, Pulls and Twists
Force Push/pull/twist Can change motion, shape of an object Measured in Newtons (N) Contact force Push/pull/twist through touching an object E.g. hammering a nail, lifting a book Weight force Movement caused by gravity © Andrew Newbound 2013
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Pushes, Pulls and Twists
Reaction force Pushes against your force Stops you from crashing through the floor Friction Force that slows movement Pushes against moving objects Ice = low friction surface Need to ride bike © Andrew Newbound 2013
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Mass and Weight Mass Weight Lift accelerates upward
Amount of matter inside an object Measured in kg Weight Downwards force Depends on your body’s mass + strength of gravity Measured in Newtons (N) Lift accelerates upward Floor pushes upwards Feet push harder against floor Extra weight © Andrew Newbound 2013
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Mass and Weight Weightlessness Neutron star = 10 million x mass
Occurs when there is no gravity Neutron star = 10 million x mass © Andrew Newbound 2013
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Drawing Forces Vector Arrow used to draw force Longer = more force
© Andrew Newbound 2013
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1. Law of Inertia Upwards push of road Resistance forces Thrust Weight
© Andrew Newbound 2013
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1. Law of Inertia Newton’s First Law of Motion states that an object will remain at rest, or will not change its speed or direction, unless it is acted upon by an outside, unbalanced force. Constant speed = balanced forces Seatbelt Keeps passenger moving with vehicle Prevents law of ineria © Andrew Newbound 2013
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2. 𝑭=𝒎𝒂 Newton's Second Law of Motion describes how the mass of an object affects the way that it moves when acted upon by one or more forces. Larger objects accelerate less rapidly than smaller object acted upon with the same force. Inertia Property of object that makes them resist change © Andrew Newbound 2013
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2.𝑭=𝒎𝒂 Rocket accelerates 𝐹 𝛼 𝑎 More mass = more inertia
Loses mass yet has same force 𝐹 𝛼 𝑎 Acceleration is proportionate to force More mass = more inertia © Andrew Newbound 2013
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Net Force; Resultant Force
Sum of forces acting upon it Taking into account their direction Same side + Different – 𝐹𝑜𝑟𝑐𝑒 𝑛𝑒𝑤𝑡𝑜𝑛𝑠 =𝑚𝑎𝑠𝑠 𝑘𝑔 ×𝑎𝑐𝑐𝑒𝑙𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛(𝑚/ 𝑠 2 ) © Andrew Newbound 2013
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Action/Reaction ‘For every action there is an equal and opposite reaction.’ OR ‘If one object pushes on another object, then the other object pushes back with equal force.’ Stand on floor Weight force (downwards)=upward force of floor action reaction Unbalanced Move in dirrection © Andrew Newbound 2013
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Action Reaction Slippery floor Moving in space
Move foot, lower force reaction ∴ slip Moving in space Cylinders of compressed gas attached to space suits © Andrew Newbound 2013
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Momentum 𝑚𝑜𝑚𝑒𝑛𝑡𝑢𝑚 (𝑘𝑔.𝑚/𝑠)=𝑚𝑎𝑠𝑠 (𝑘𝑔)×𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦(𝑚/𝑠)
More momentum = harder to stop © Andrew Newbound 2013
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Car Safety Reducing number of accidents Reducing injuries Seatbelts
Hold occupants in their seas Absorb inertia Headrest Reduce whiplash from inertia Crumple zone Crumples to absorb energy © Andrew Newbound 2013
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Car Safety Air bags Anti-lock brake systems (ABS) Deep tread
Absorb inertia & deceleration forces of occupants Anti-lock brake systems (ABS) Stop wheels from skidding Friction lost with road Deep tread Maximum friction Twice as fast = 4 times longer to stop © Andrew Newbound 2013
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Car Safety Reaction time Reaction distance Braking distance
Time taken for driver to react to danger Moving from accelerator to the brake Reaction distance Distance car travels during reaction time Braking distance Distance taken for car to stop when brakes are applied Stopping distance Total distance © Andrew Newbound 2013
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Car Safety Alcohol & fatigue Law 1 Law 2 Law 3 Lower concentration
Increase reaction time Stop. Revive. Survive. Law 1 Seatbelts Headrests Law 2 Airbags Crumple zones Law 3 ABS Tire tread © Andrew Newbound 2013
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Physics Crash Video 2 cars crash at 80km/h 𝐾𝐸= 1 2 𝑚 𝑟 2
= single car crashing into solid barrier 𝐾𝐸= 1 2 𝑚 𝑟 2 3x speed = 9x stopping distance 4x speed = 16x stopping distance 50km/h accident Dropped from a 3 storey building 100km/h accident Dropped from a 12 storey building © Andrew Newbound 2013
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Getting Into Genes Topic 3 © Andrew Newbound 2013
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Glossary Alleles Chromosome Dominant Gametes
The alternative forms of each gene Chromosome A length of DNA, containing many genes Dominant The one of a pair of opposite characters that appears when both are inherited Gametes The sex cells – sperm and ova © Andrew Newbound 2013
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Glossary Genetics Genotype Heredity Heterozygous
The study of inheritance and variation and the factors controlling them Genotype The genetic make-up of an individual Heredity Passing on characteristics from one generation to the next Heterozygous Different alleles for a gene © Andrew Newbound 2013
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Glossary Homozygous Meiosis Mendel 2 of the same alleles for a gene
Cell division resulting in daughter cells with half the chromosome number of the parent cell. (makes the sex cells) Mendel An Austrian monk who carried out experiments on pea plants ‘The father of genetics © Andrew Newbound 2013
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Glossary Mitosis Mutation Phenotype Recessive Zygote
Cell division resulting in in 2 daughter cells each an exact copy of the parent cell Mutation Results when a mistake is made in copying of DNA Phenotype How living things appear and function Recessive Appearing in offspring only when not masked by a dominant characteristic Zygote The 1st cell of a new individual, formed when a sperm fuses with the ova during fertilisation © Andrew Newbound 2013
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Cells & Organisms All living things made of cells/product of cells
Cell theory Unicellular Only have 1 cell E.g. bacteria Multicellular All familiar plants & animals © Andrew Newbound 2013
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Cells Functions Take in substances (assimilate)
Extract energy from food Excrete their wastes Grow Reproduce Respond to things Parts Nucleus Control centre Cell membrane Controls what gets in/out Cytoplasm Liquid containing various structures (organelles) © Andrew Newbound 2013
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Plant Cells Additions Chloroplasts Make food Cell wall
Strengthens structure Vacuoles Store water & dissolved substances Smaller/none in animal cells © Andrew Newbound 2013
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Body System Structure Cells Tissues Organs Body systems
© Andrew Newbound 2013
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Cells to Systems All cells = same size Cells need body systems
Just diff quantity Cells need body systems Need food, water & oxygen Delivered by body systems © Andrew Newbound 2013
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Plant Cell cytoplasm © Andrew Newbound 2013
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Microscope © Andrew Newbound 2013
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Microscope Eyepiece lens Microscope tube
Bends the light to make the object look bigger Microscope tube Light travels through it to the eyepiece Coarse focus & fine focus knobs Moves the lens up/down so that the object can be seen clearly Objective lens Can be changed so that the object can be magnified more or less © Andrew Newbound 2013
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Microscope Stage Mirror Base
Holds the slide with the object you are looking at in place Mirror Makes light bounce through the slide into the lens Base Holds the microscope up © Andrew Newbound 2013
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The Cell – How it Works Cell tissue e.g. Multi-cellular Cell membrane
Muscle, nerve, skin Multi-cellular Large groups of cells which specialise Cell membrane Outside of cell Cytoplasm Liquid inside cell All except nucleus Semi-transparent Includes cytosol, various organelles © Andrew Newbound 2013
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The Cell – How it Works Organelles Nucleus Nucleus = most prominent
Mitochondria Cytoskeleton Ribosomes Golgi complex Lysomes Nucleus Contains DNA & runs the cell © Andrew Newbound 2013
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Cellular Organisation
Animal Muscle cell Muscle Artery Circulatory System Horse Plant Epidermal cell Epidermis Leaf Photosynthesis system (leaves & stem) Whole plant © Andrew Newbound 2013
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What Cells Need to Survive
Cannot function without food & water Correct temperature <0°C = cell stops functioning Water freezes Respiration Burning of food w/ oxygen = energy 𝐹𝑂𝑂𝐷+𝑂𝑋𝑌𝐺𝐸𝑁 →𝐸𝑁𝐸𝑅𝐺𝑌+𝐶𝐴𝑅𝐵𝑂𝑁 𝐷𝐼𝑂𝑋𝐼𝐷𝐸+𝑊𝐴𝑇𝐸𝑅 © Andrew Newbound 2013
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What Cells Need to Survive
Energy is needed for Growth Reproduction Other functions © Andrew Newbound 2013
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Cell Organelles Nucleus Nuclear membrane Cell membrane Contains DNA
Control centre of cell Nuclear membrane Surrounds the nucleus Lets in and out RNA Chemical copy of DNA Used to make protein Cell membrane Controls entry and exit of chemicals © Andrew Newbound 2013
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Cell Organelles Protoplasm Cytoplasm Mitochondria Ribosomes
All contents of cell Cytoplasm All contents of cell except nucleus Mitochondria Produces energy from food Ribosomes Manufactures protein Endoplasmic reticulum Moves products through the membrane © Andrew Newbound 2013
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Cell Organelles Chloroplasts Lysosomes Microfilaments/cytoskeleton
Contains chlorophyll Used for photosynthesis Lysosomes Stores enzymes Microfilaments/cytoskeleton Holds organelles in place Vacuoles Stores food & minerals © Andrew Newbound 2013
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Nuclear Matter Nucleic acids DNA RNA Generally located in nucleus
Deoxyribonucleic acid Stores coded instructions Double helix Watson and Crick RNA Ribonucleic acid Allows DNA to read coded instructions Generally located in nucleus Prokaryote It is located in an area of the cell Not in a membrane © Andrew Newbound 2013
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Nuclear Matter Nucleus Nucleus=programmed by DNA Control centre
Instructions For making all parts of cell Way cell behaves How carry out functions Transmitting Nerve impulse Supplying energy Contracting (muscle cells) Carrying out photosynthesis © Andrew Newbound 2013
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Nuclear Matter Nuclear membrane’s pores
Connect with endoplasmic reticulum Transport material in and out of nucleus Nucleus need to be stained to be visible under a microscope © Andrew Newbound 2013
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Nuclear Matter - Chromosomes
Shorted and coiled forms of DNA made when the cell is about the divide Only visible when stained Human cell 23 pairs 46 individual Sex chromosomes Information for sexual characteristics Autosomes Non-sex chromosomes © Andrew Newbound 2013
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Karyotyping Process of sorting chromosomes into their matched pairs
Important in investigating chromosomal disorders © Andrew Newbound 2013
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Mitosis Parent cell Chromosomes duplicate (chromatid pairs)
Chromosomes appear as long thin threads Chromosomes duplicate (chromatid pairs) Become shorter and thicker Chromatid pairs line up Along the equator of the cell Chromatids separate Move to opposite ends of cell Starts to split into 2 cells Daughter cells Chromosomes become longer, thinner and less distinct © Andrew Newbound 2013
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Mitosis Homologous Pair Diploid Haploid Daughter cell
Chromosomes exist in pairs in each body cell. One pair from the mother, one pair from the father Diploid 2 of each type of chromosome Haploid Genetes (ova/sperm) contain only 1 of each type of chromosome Daughter cell Cell that is an exact copy of parent cell due to MITOSIS © Andrew Newbound 2013
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Mitosis Occurs in all body parts except sex cells
Multicellular organism purpose Growth and repair Single-celled organism purpose Reproduction © Andrew Newbound 2013
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Meiosis Very complex form of cell division Begins same as mitosis
Occurs only in reproductive organisms Ovaries & testes in humans After duplication of chromosomes From “half-cells” ½ of correct number of chromosomes for organism Fertilisation Recombine to give correct no. of chromosomes © Andrew Newbound 2013
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Meiosis Ova 23 Sperm 23 Zygote © Andrew Newbound 2013
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Meiosis 2 pairs of chromosomes are visible Chromosomes double
Joined at centromere Homologous pairs line up along equator One of each pair moves to ends of cell Chromosomes line up along equator Chromosomes separate + move to ends of cell Membranes form to produce 4 daughter cells © Andrew Newbound 2013
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Building DNA Made of many nucleotides 4 bases
Joined like links in a chain Made of sugar – deoxyribose + phosphoric acid + nitrogenous base 4 bases Adenine Thymine Guanine Cytosine Order determines chemical code © Andrew Newbound 2013
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Building DNA Copied RNA Genome Unzips along bases Like DNA
In every cell Sugar = ribose Base uracil instead of Thymine Used to make copies of DNA Genome Sequence of bases in the DNA/RNA of a living thing Human = 3100 million base pairs © Andrew Newbound 2013
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How DNA Works Gene Chromosome DNA Length of DNA Sequence of bases
Code for 1 protein Chromosome Length of genes DNA Carries all instructions for cell to function Copied onto carrier molecule Messenger RNA M-RNA © Andrew Newbound 2013
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How DNA Works m-RNA Cells differentiate Stem cells
Moves out through nuclear membrane Into cytoplasm of cell At ribosomes Translated into protein Cells differentiate As multicellular organisms grow Specialise into different roles & tasks Stem cells Cells which aren’t specialised Take on any task © Andrew Newbound 2013
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Biotechnology DNA Gene Chromosome The material that genes are made of
Deoxyribonucleic acid Gene Coded instructions that control our development & body function Chromosome Collections of genes Wound in double helix 23 from each parent © Andrew Newbound 2013
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Biotechnology Mutation Biotechnology Clone
Changes in the code of genes Biotechnology The exploitation of biological processes for industrial and other prospects Clone Any organism with identical genes to their parent organism © Andrew Newbound 2013
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Human Genome Project Completely decode human blueprint
Fund laps to map genes of humans Physical + gene maps Needs 15 years 3 billion bases in genome © Andrew Newbound 2013
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Human Genome Project Pros Prevent genetic conditions
Testing genes early on Cons Insurance companies could use info Introduction of new genes could make others worse Parents may not want to know their condition © Andrew Newbound 2013
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GM Food Foods derived from genetically modified organisms
E.g. soybean, corn, canola & cotton seed oil © Andrew Newbound 2013
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GM Food Advantages Lower price Reduces use of toxic chemicals
Prevents wasted crops Solve hunger Grow foods in different climates Improve vitamin & mineral content Faster growth Disadvantages Lasting effects on other species Natural immunity of insects to GM plant changes Ownership of food Allergens © Andrew Newbound 2013
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Dolly – The Cloned Sheep
1st mammal cloned from an adult cell 5th July 1996 Produced 6 lambs 2003 Experienced progressive lung disease + severe arthritis Euthanized Possible cause of short life Born at age of 6 years Only had 6 left © Andrew Newbound 2013
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Cloning Eliminate famine Eliminate STIs Social discrepancy
Only few able to achieve © Andrew Newbound 2013
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Dr Fiona Wood AM Born Feb 2 1958 Discovered in 1990
Treatment of cultivating skins from patient = ineffective Requires days Scaring likely to occur Burn wounds taking 21+ days to heal Scaring less likely to occur <10 days © Andrew Newbound 2013
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Dr Fiona Wood AM Skin sheets produced in 10 days Spray on skin
More could be done Spray on skin CellSpray Aerosol delivery system Apply cultivated skin to larger burn areas Treat burns victims quicker Noticeable during Bali Bombings © Andrew Newbound 2013
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Reading the Code DNA RNA/m-RNA Carries code for making proteins
Form our bodies Made from proteins/products made by proteins Makes 20 diff amino acids 3 bases code for each amino acid + start and stop RNA/m-RNA Opposite to code for DNA Complementary Occurs during mitosis © Andrew Newbound 2013
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Reading the Code Genetic fingerprinting
Using someone’s DNA to establish their identity Relies on enzymes Break DNA into short lengths Separated by Chroma typing Uses: Forensic work Confirming pedigree of valuable animals Checking genetic diversity of endangered animals © Andrew Newbound 2013
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Figure thing © Andrew Newbound 2013
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Mutations Spontaneous change in gene/chromosome
Alteration in related characteristic Increased rate due to mutagens Mutation-causing agents E.g. X-rays Gamma rays Ultraviolet light Range of chemicals including benzene Responsible for genetic variation we see today © Andrew Newbound 2013
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Gregor Mendel Discovered + made detailed investigations of base principals of heredity How traits are inherited Used pea plants Started w/ pure breeding Hybrids Plants produced by crossing contrasting breeding plants © Andrew Newbound 2013
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Gregor Mendel Dominant characteristic Recessive characteristic Genes
Strong form Recessive characteristic Weak characteristic Genes Small factors that controlled inheritance Alles Diff forms of a gene E.g. purple and white colours in flowers © Andrew Newbound 2013
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Gregor Mendel Phenotype Genotype Appearance of new offspring
Combination of genes that determine a phenotype © Andrew Newbound 2013
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Gregor Mendel P generation (Breeding Parents)
F1 generation (first filial generation) F2 generation (2nd generation) © Andrew Newbound 2013
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Punnett Square S s Ss ss Short hair hybrid dog (Ss) and long haired hybrid dog (ss) with long hair being recessive © Andrew Newbound 2013
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Heterozygous/Homozygous
Different alles Homozygous Same alles © Andrew Newbound 2013
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Human Inheritance 23 pairs of chromosomes 100,000 diff genes
Linked genes Lying near each other on the same chromosome Particular characteristic Determined by 1 dominant/recessive genes Incomplete dominance Halfway between 2 genes © Andrew Newbound 2013
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Sex Determination Females Males
22 normal pairs of chromosomes + XX pair of sex chromosomes Males 22 normal pairs of chromosomes + XY pair of sex chromosomes © Andrew Newbound 2013
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Sex Determination X Y XX XY Genotype: XX : XY 50% : 50%
50% : 50% Phenotype: Female : Male © Andrew Newbound 2013
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Sex Determination Sex linked Sex linked genetic diseases
Genes found on the X and Y chromosome Y chromosome only has a few genes compared to the X chromosome Sex linked genetic diseases Caused by defective genes on X chromosome and occur more frequently in males than females E.g. colour blindness © Andrew Newbound 2013
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Colour Blindness Females Males
Must contain 2, reate faulty genes to be colour blind X`X` 1 faulty gene = carrier Dominant normal gene = proper vision Males Need only one faulty gene to be colourblind X`Y © Andrew Newbound 2013
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Colour Blindness X` Y X XX` XY Normal mother and a colour-blind father
Genotype XX`:XY Phenotype Female Male Carrier Normal © Andrew Newbound 2013
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Colour Blindness X` Y XX` X`Y X XY
Normal mother and a colour-blind father Genotype XX`:X`X`:XY:X`Y Carrier Carrier: Colour blind: Normal: colour blind Phenotype Female:Female:Male:Male © Andrew Newbound 2013
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Chemical Changes Topic 4 © Andrew Newbound 2013
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Spelling List Chemistry Model Charge
Scientific study of matter, its properties and its interaction with other matter and energy Model A representation of something based on a set of assumptions, usually determined through experiments Charge The net effect of losing or gaining atoms © Andrew Newbound 2013
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Spelling List Atom Element Molecule Compound
The smallest particle of an element Element A substance made up of only 1 part of an atom Molecule A group of atoms joined by bonds Compound A group of different atoms that are joined in a fixed ratio © Andrew Newbound 2013
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Spelling List Periodic table Electron shells Chemical formula
The arrangement of elements into a table of groups and periods Electron shells The arrangement of electrons around the nucleus, based on energy levels Chemical formula A shorthand way of writing the name of an element or compound © Andrew Newbound 2013
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Spelling List Word equation Chemical reaction Reactant Products
Shows the changes that occur in a chemical reaction using words Chemical reaction Interactions in which atoms exchange or share electrons forming new chemical compounds Reactant The chemical compounds that combine to start a chemical reaction Products The chemical compounds that are produced during a chemical reaction © Andrew Newbound 2013
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Chemistry Revision © Andrew Newbound 2013 All Substances
Pure Substances Element Compound Mixtures © Andrew Newbound 2013
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Chemistry Revision Element Compound Molecule
Cannot be broken down into simpler substances E.g. oxygen, argon and helium Compound Pure substance that can be broken down E.g. sodium chloride Combined elements Molecule Joined atoms © Andrew Newbound 2013
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What are Atoms Made of? Element Can’t look at atoms
Not made of anything except self 92 in nature Many too unstable Can’t look at atoms Too small Everything we look with is made of atoms Indirect evidence How it affects what is around it © Andrew Newbound 2013
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What are Atoms Made of? Proton Neutron Electron Define the element
Positively charged In nucleus Neutron No charge Create diff isotopes of element Electron Negatively charged Orbiting nucleus © Andrew Newbound 2013
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What are Atoms Made of? Ion Isotype Nucleus Charged atom
Different number of protons to electrons Isotype Atoms of element with different number of neutrons Nucleus Makes up 1/10,000 of space in atom Mostly empty space © Andrew Newbound 2013
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What are Atoms Made of? Rutherford Fired alpha particles at gold leaf
2 protons + 2 neutrons Positive charge Expected to steer away & he would measure how much they changed direction Actually didn’t change direction very much Many came back at him © Andrew Newbound 2013
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What are Atoms Made of? Niels Bohr Colours in emission spectra
Electrons occupy own orbitals Colours in emission spectra Represent element giving off light Represents energy level Outer shell Valance shell Occupied by high energy electrons Predicts properties & reactivity © Andrew Newbound 2013
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What are Atoms Made of? The Periodic Table Discovered by Mendeleev
Patterns appeared periodically Gaps would be filled by elements Predicted properties © Andrew Newbound 2013
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What are Atoms Made of? Chemical symbol Atomic number Atomic weight
Unique 1-3 letters E.g. C=carbon, Cl=Chlorine Atomic number Number of protons in 1 atom of element Atomic weight Average weight of 1 atom of element Different isotopes Carbon = © Andrew Newbound 2013
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What are Atoms Made of? Group
Number of electrons in outer shell (Valence electrons) Alkali metals 1 Alkali Earth metals 2 Noble gases 8 Halogens 7 © Andrew Newbound 2013
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What are Atoms Made of? Period Number of electrons in shell
Row of elements Number of electrons in shell 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑠ℎ𝑒𝑙𝑙 2 ×2 © Andrew Newbound 2013
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What are Atoms Made of? © Andrew Newbound 2013
Only 1 electron in outer shell Very reactive Can be easily lost Wants to lose E.g. Lithium, sodium Needs 1 electron in outer shell Strongly attracts elements to fill shell E.g. Iodine, bromine, chlorine, fluorine © Andrew Newbound 2013
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What are Atoms Made of? 𝑆𝑜𝑑𝑖𝑢𝑚+𝑐ℎ𝑙𝑜𝑟𝑖𝑛𝑒→𝑠𝑜𝑑𝑖𝑢𝑚 𝑐ℎ𝑙𝑜𝑟𝑖𝑑𝑒
Sodium donates 1 electron to chlorine Makes stable Compound Not mixture Not similar properties to reactants © Andrew Newbound 2013
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What are Atoms Made of? © Andrew Newbound 2013 Ionic Bonding
1 positive (cation) & 1 negative (anion) Covalent Bonding Share electrons Not as reactive © Andrew Newbound 2013
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Chemical Building Blocks
~ 400BC Democritus All substances consist of indestructible particles called atoms 1808 John Dalton All matter consisted of atoms Could not be divided Same element = alike Combined in whole number ratios © Andrew Newbound 2013
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Chemical Building Blocks
1897 Sir J.J Thomson Plumb pudding 1911 Lord Rutherford Nuclear model for atom 1913 Niels Bohr Electrons orbit at different energy levels 1932 Sir James Chadwick Discovered neutrons © Andrew Newbound 2013
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Chemical Building Blocks
Protons + In nucleus Electrons - Orbit nucleus of proton Neutrons Neither +/- About same size as proton © Andrew Newbound 2013
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Looking into Atoms Mass number No. of protons + neutrons
© Andrew Newbound 2013
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The Periodic Table Shows trends in properties between elements
Predict properties of elements Most elements are solids 2 elements are liquid at room temp (25º) Some melt just above 11 elements gases at room temp Heaviest natural = uranium © Andrew Newbound 2013
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Electrons and Atoms Electrons Determine chemical properties of element
Orbit in layers/shells Same number as protons 2 fill 1st shell 8 fill 2nd shell 8 fill 3rd shell (1st 20 elements) 4th shell = partly filled Jump to higher energy level when heated © Andrew Newbound 2013
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Electrons and Atoms Electron configuration E.g. aluminium = 2.8.3
© Andrew Newbound 2013
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Chemical Changes Periodic table Element Compound Symbol
Chart showing all elements in order of atomic number Element Pure substances made of billions of same type of atom Compound Pure substance made of billions of same type of molecule Symbol Short way of writing chemical name © Andrew Newbound 2013
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Chemical Changes Formula Molecule Electrolysis Decomposition Proton
Way of writing type & ratio of atoms in a compound Molecule Group of atoms joined in a fixed ratio Electrolysis Using electricity to cause a chemical change Decomposition Breakdown of compound into simpler substances Proton Part of nucleus of atom that determines identity of atom Electron Orbits nucleus of atom in energy shell © Andrew Newbound 2013
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OPTIONAL CONTENT MAY GO HERE
© Andrew Newbound 2013
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Reading Equations Chemical equation Balanced equation
Shows more than word equation Ratios and types of atoms present Balanced equation Shows even more Atoms only change positions Not created/destroyed Not shown in chemical equation Energy changes Rate (speed) of reaction How reactants change into products © Andrew Newbound 2013
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𝐴𝑐𝑖𝑑+𝑏𝑎𝑠𝑒 →𝑠𝑎𝑙𝑡+𝑤𝑎𝑡𝑒𝑟
Reactions With Acids 𝐴𝑐𝑖𝑑+𝑏𝑎𝑠𝑒 →𝑠𝑎𝑙𝑡+𝑤𝑎𝑡𝑒𝑟 © Andrew Newbound 2013
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Reactions With Acids Salts Hydrochloric acid Sulphuric acid
Ionic compounds Hydrochloric acid Chloride salts Sulphuric acid Sulphates © Andrew Newbound 2013
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𝑀𝑒𝑡𝑎𝑙+𝑎𝑐𝑖𝑑 →𝑠𝑎𝑙𝑡+ℎ𝑦𝑑𝑟𝑜𝑔𝑒𝑛
Reactions With Acids 𝑀𝑒𝑡𝑎𝑙+𝑎𝑐𝑖𝑑 →𝑠𝑎𝑙𝑡+ℎ𝑦𝑑𝑟𝑜𝑔𝑒𝑛 © Andrew Newbound 2013
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𝑀𝑒𝑡𝑎𝑙 𝑜𝑥𝑖𝑑𝑒+𝑎𝑐𝑖𝑑 →𝑠𝑎𝑙𝑡+𝑤𝑎𝑡𝑒𝑟
Reactions With Acids 𝑀𝑒𝑡𝑎𝑙 𝑜𝑥𝑖𝑑𝑒+𝑎𝑐𝑖𝑑 →𝑠𝑎𝑙𝑡+𝑤𝑎𝑡𝑒𝑟 © Andrew Newbound 2013
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𝐴𝑐𝑖𝑑𝑠+𝐶𝑎𝑟𝑏𝑜𝑛𝑎𝑡𝑒𝑠 →𝑆𝑎𝑙𝑡+𝑊𝑎𝑡𝑒𝑟 +𝐶𝑎𝑟𝑏𝑜𝑛 𝐷𝑖𝑜𝑥𝑖𝑑𝑒
Carbonates 𝐴𝑐𝑖𝑑𝑠+𝐶𝑎𝑟𝑏𝑜𝑛𝑎𝑡𝑒𝑠 →𝑆𝑎𝑙𝑡+𝑊𝑎𝑡𝑒𝑟 +𝐶𝑎𝑟𝑏𝑜𝑛 𝐷𝑖𝑜𝑥𝑖𝑑𝑒 © Andrew Newbound 2013
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Acids & Bases in the Home
Common acids Hydrochloric Sulphuric Corrosive = harmful Damage/eat away material it touches © Andrew Newbound 2013
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Acids & Bases in the Home
Sour Corrosive Lose hydrogen in water Base Bitter Slippery Eat away proteins Lose hydroxide in water © Andrew Newbound 2013
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Acids & Bases in the Home
Indicator Changes colour in different conditions Acids & bases Litmus Red = acid Blue = base Water = neutral Neutralisation reaction Acid + base © Andrew Newbound 2013
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Acids & Bases in the Home
Citric acid Cola drinks Milk Shampoo Bases Laundry powder Soap Dishwashing detergent Oven cleaners © Andrew Newbound 2013
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Precipitates Change of chemical partners Cloudy mixture formed
© Andrew Newbound 2013
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Precipitates © Andrew Newbound 2013 Soluble Sodium salts
Potassium salts Ammonium salts Most sulfates Calcium sulfate = slightly soluble Sodium carbonates Potassium carbonate Ammonium carbonate Insoluble Sulfates Lead Barium Most carbonates © Andrew Newbound 2013
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Chemical Changes Ionic Covalent Ion
Type of compound made from attraction of metal and non-metal ions Covalent Type of compound made from two non-metals that share electrons Ion An atom that has lost or gained electrons and now carries an electrical charge © Andrew Newbound 2013
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Chemical Changes Lattice Flame test Equation
Large array of atoms or ions that repeats itself millions of times Flame test Where the colours of the flame are used to identify the types of atoms present Equation A written record of the reactants and products in a chemical reaction © Andrew Newbound 2013
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Chemical Changes Limewater Limestone Precipitate Suspension
Reagent used to test for presence of carbon dioxide Limestone Type of rock dissolved away by carbon dioxide gas dissolved in rainwater Precipitate An insoluble substance that forms when ions come together Suspension An insoluble substance shaken in water © Andrew Newbound 2013
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Chemical Changes Element Decomposition Neutralisation Precipitate
A pure substance made of only one type of atom Decomposition When a group of atoms breaks apart into smaller groups Neutralisation Reaction where an acid and a base react and destroy each other Precipitate An insoluble substance made from the reaction of any two soluble substances © Andrew Newbound 2013
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Chemical Changes Covalent Ionic Compound
Groups of compounds formed from atoms of non-metals Ionic Groups of compounds formed from metal and non-metal ions Compound A pure substance made of 2 or more different atoms joined in a fixed ratio © Andrew Newbound 2013
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Chemical Changes Electron Calcium carbonate Flame test
The outermost part of an atoms that can be lost or gained in chemical reactions Calcium carbonate The chemical compound present in lime, limestone, caves, chalk and cement Flame test Procedure where atoms are heated and the colours they produce are recorded © Andrew Newbound 2013
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Chemical Changes Hydrochloric acid chloride salts
Sulfuric acid sulfate salts Nitric acid nitrate salts Phosphoric acid phosphate salts © Andrew Newbound 2013
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Chemical Reactions Combustion (burning) Corrosion E.g.
𝑚𝑒𝑡ℎ𝑎𝑛𝑒+𝑜𝑥𝑦𝑔𝑒𝑛→𝑐𝑎𝑟𝑏𝑜𝑛 𝑑𝑖𝑜𝑥𝑖𝑑𝑒+𝑤𝑎𝑡𝑒𝑟 Corrosion 𝑙𝑒𝑎𝑑 𝑛𝑖𝑡𝑟𝑎𝑡𝑒+𝑝𝑜𝑡𝑎𝑠𝑠𝑖𝑢𝑚 𝑖𝑜𝑑𝑖𝑑𝑒 →𝑙𝑒𝑎𝑑 𝑖𝑜𝑑𝑖𝑑𝑒+𝑝𝑜𝑡𝑎𝑠𝑠𝑖𝑢𝑚 𝑛𝑖𝑡𝑟𝑎𝑡𝑒 © Andrew Newbound 2013
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Chemical Reactions Acids + metals Acids + carbonates
𝑀𝑒𝑡𝑎𝑙+𝐴𝑐𝑖𝑑→𝑆𝑎𝑙𝑡+𝐻𝑦𝑑𝑟𝑜𝑔𝑒𝑛 E.g. 𝑚𝑎𝑔𝑛𝑒𝑠𝑖𝑢𝑚+ℎ𝑦𝑑𝑟𝑜𝑐ℎ𝑙𝑜𝑟𝑖𝑐 𝑎𝑐𝑖𝑑 →𝑚𝑎𝑔𝑛𝑒𝑠𝑖𝑢𝑚 𝑐ℎ𝑙𝑜𝑟𝑖𝑑𝑒+ℎ𝑦𝑑𝑟𝑜𝑔𝑒𝑛 Acids + carbonates 𝐴𝑐𝑖𝑑+𝐶𝑎𝑟𝑏𝑜𝑛𝑎𝑡𝑒→𝑆𝑎𝑙𝑡+𝑊𝑎𝑡𝑒𝑟+𝐶𝑎𝑟𝑏𝑜𝑛 𝐷𝑖𝑜𝑥𝑖𝑑𝑒 𝑠𝑢𝑙𝑓𝑢𝑟𝑖𝑐 𝑎𝑐𝑖𝑑+𝑐𝑜𝑝𝑝𝑒𝑟 𝑐𝑎𝑟𝑏𝑜𝑛𝑎𝑡𝑒 →𝑐𝑜𝑝𝑝𝑒𝑟 𝑠𝑢𝑙𝑓𝑎𝑡𝑒+𝑤𝑎𝑡𝑒𝑟+𝑐𝑎𝑟𝑏𝑜𝑛 𝑑𝑖𝑜𝑥𝑖𝑑𝑒 © Andrew Newbound 2013
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Chemical Reactions Neutralisation
Acids are neutralised (cancelled) bases pH 7 (neutral) 𝐴𝑐𝑖𝑑+𝐵𝑎𝑠𝑒→𝑆𝑎𝑙𝑡+𝑊𝑎𝑡𝑒𝑟 E.g. 𝐻𝑦𝑑𝑟𝑜𝑐ℎ𝑙𝑜𝑟𝑖𝑐 𝑎𝑐𝑖𝑑+𝑠𝑜𝑑𝑖𝑢𝑚 ℎ𝑦𝑑𝑟𝑜𝑥𝑖𝑑𝑒 →𝑠𝑜𝑑𝑖𝑢𝑚 𝑐ℎ𝑙𝑜𝑟𝑖𝑑𝑒+𝑤𝑎𝑡𝑒𝑟 © Andrew Newbound 2013
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Chemical Reactions Decomposition Combination
∆≡ℎ𝑒𝑎𝑡 Decomposition Single compound is broken down/decomposed Form 2≤ products E.g. 𝑐𝑜𝑝𝑝𝑒𝑟 𝑐𝑎𝑟𝑏𝑜𝑛𝑎𝑡𝑒→∆→𝑐𝑜𝑝𝑝𝑒𝑟 𝑜𝑥𝑖𝑑𝑒+𝑐𝑎𝑟𝑏𝑜𝑛 𝑑𝑖𝑜𝑥𝑖𝑑𝑒 Combination 2 elements combining to form a single compound 𝐼𝑟𝑜𝑛+𝑠𝑢𝑙𝑓𝑢𝑟𝑒→𝑖𝑜𝑛 𝑠𝑢𝑙𝑓𝑖𝑑𝑒 © Andrew Newbound 2013
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Chemical Reactions - Tests
Oxygen Glowing split will burst into flames in oxygen Carbon dioxide Burning splint is put out Limewater turns milky Hydrogen Pop test © Andrew Newbound 2013
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Chemical Reactions Moisture Nitrogen dioxide
Often visible around top of a test tube when heating a substance that contains water Nitrogen dioxide Brown-orange coloured gas © Andrew Newbound 2013
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Waves & Energy Topic 5 © Andrew Newbound 2013
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Waves & Energy Waves & radiation Sound waves Carries energy
Formed when particles are pushed from normal/rest position Springs back to where they were Pushes on near particles Sound waves Longitudinal wave motion Move to and fro in the same & opposite direction to the wave Move in direction of wave & return to original position Energy is pushed © Andrew Newbound 2013
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Waves & Energy Compressions Rarefactions Longitudinal waves e.g.
Particles move closer together Rarefactions Spread further apart Longitudinal waves e.g. Sound waves Explosions Some earthquake waves Force of explosion Pushes air away Transferred energy Strong enough to break windows © Andrew Newbound 2013
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Waves & Energy Water waves Ripples travel outwards Transverse waves
At right angles Boat over water E.g. Water Pulse in spring Some earthquake waves © Andrew Newbound 2013
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Waves & Energy Progressive waves Standing waves
Move energy from one place to another Moving forwards E.g. soundwaves Standing waves Identical waves in opposite directions E.g. pulse in rubber tube Travel through substance E.g. water, sound Don’t need substance to travel through Electromagnetic Light, radio © Andrew Newbound 2013
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Waves & Energy displacement © Andrew Newbound 2013
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Waves & Energy rarefaction © Andrew Newbound 2013
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Waves & Energy Crest Trough Amplitude Top of wave Bottom of wave
Distance from normal position to crest/trough © Andrew Newbound 2013
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Waves & Energy Displacement Wavelength Frequency
Distance from crest to trough Wavelength Length of 1 wave Distance between 2 crests/2 troughs Frequency Number of waves in a certain time © Andrew Newbound 2013
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Electromagnetic Waves
Vibrating particles Carry the energy in a wave Atoms Gain energy Absorb it Re-emit it Travel at 3× 10 8 m/s Differ in wavelength & frequency No sharp boundaries between types of waves Overlap © Andrew Newbound 2013
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Types of Electromagnetic Waves
Gamma Shortest wavelength Can go through lead and concrete Medical X-Rays Affect photographic film Ultraviolet Beyond violet ‘Black light’ Cause skin cancer & sunburn Sunbeds © Andrew Newbound 2013
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Types of Electromagnetic Waves
Light Visible light Infrared Beside red light Heat radiation Passes through some gases and glass Greenhouses Trap Heating © Andrew Newbound 2013
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Types of Electromagnetic Waves
Microwaves Telecommunications Make water molecules in food vibrate Television & Radio Waves Longest wavelength TV & radio signals © Andrew Newbound 2013
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Waves & Technology Laser Light Photonics Surgery Shopping
Intense heat Cut away unwanted tissues Burn off skin blemishes Shopping Read barcodes Photonics Using light in electric appliances © Andrew Newbound 2013
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Waves & Technology Satellites cheaper than fixed lines
35880km above the earth Energy comes from solar cells Remote areas Receive all TV, radio and Internet services © Andrew Newbound 2013
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Medical Uses Imaging Being able to see where you cannot normally see
© Andrew Newbound 2013
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Medical Uses © Andrew Newbound 2013 Gamma radiation
Patient given tiny dose of radioactive atoms Recorded through gamma camera Different types for diff parts of body Ultrasound Very rapid vibrations Not detected by our ears Sound is reflected (echo) off diff parts inside body Show unborn children, heart function, blood flow, treat kidney stones & gall stones X-Rays More absorbed by denser parts of body © Andrew Newbound 2013
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Medical Uses: X-Rays © Andrew Newbound 2013 CAT Scans CT scans
X-Rays concentrated on small slices Computerised Axial Tomography Detector records intensity of X-Rays Treat Cancer Can kill cells Particularly rapid growth ones © Andrew Newbound 2013
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Medical Uses: X-Ray Protection
Placed close to patient Not scattered by dust No-one else in room at time Machine placed in room with thick concrete walls Absorb X-Rays Entry to X-Ray room is along zig-zag hallway Stops X-Rays being reflected into busy corridors Radiation monitoring badges Thermoluminescent dosimeters (TLDs) Check radiation levels © Andrew Newbound 2013
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Waves Able to transmit energy Transverse waves Compression waves
Without moving matter Transverse waves E.g. waves on the surface of water Compression waves E.g. sound waves Vibrations Cause sounds Cause compressions & rarefactions © Andrew Newbound 2013
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Waves Medium Frequency Pitch Sound Electromagnetic waves
Material which waves travel through Frequency Number of complete waves made in 1 second Pitch Determined by frequency Sound Travels faster in solids & liquids than gases Electromagnetic waves Travel through air at 3× 10 5 Can travel through a vacuum © Andrew Newbound 2013
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Water Waves in the Ocean
Not formed on lakes Not enough space Size of wave Determined by strength + speed of wave Diffraction Waves spreading out when they approaches shallower water Wave hits a cliff/breaks into a beach Kinetic energy ⇒ sound + heat energy © Andrew Newbound 2013
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Water Waves in the Ocean
Waver blows over ocean Energy is transferred from wind to wave © Andrew Newbound 2013
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Water Waves in the Ocean
Breaking waves Sucks up water to support itself Not enough since gets shallower Rips Move straight out Swim sideways if caught in one No waves breaking Used by surfers to get out quicker © Andrew Newbound 2013
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Riding on a Light Beam Rays Beam Transparent Translucent
Lines used to show the path of light Beam Stream of light rays Visible Particles in substances scatter it Transparent Most light travels through a substance Translucent Let just enough light to detect objects on other side Can’t see objects clearly © Andrew Newbound 2013
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Riding on a Light Beam Opaque
Substances which absorb or reflect all light striking them © Andrew Newbound 2013
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Reflections Convex Mirror (Diverging mirror) Concave mirror
(Converging mirror) © Andrew Newbound 2013
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∠𝑖=∠𝑟 Reflections Angle of incidence = angle of reflection
© Andrew Newbound 2013
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Mirrors Image Image in curved mirror Concave mirror Convex mirror
Something that we see that is not really where we see it Image in curved mirror Distorted Concave mirror Enlarged image Convex mirror Wide view © Andrew Newbound 2013
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Using Lenses Piece of glass/plastic with curved sides
Shaped to bend light rays in new directions Shape of lens Amount of refraction of light Size & type of image Simple camera lens - convex Focuses light to give sharp image on film Convex lens at front of eye Focuses light onto cells at the back of our eyes © Andrew Newbound 2013
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Refraction of Light Changes in speed at the boundary
Bends towards normal © Andrew Newbound 2013
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Colour Rainbow Dispersion Filter A spectrum of light
Light from sun = separated Dispersion Separation of light into its colours Filter Plastic sheet Absorbs some colours but lets others pass through © Andrew Newbound 2013
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Colour Tiny particles of dust & water vapour
Scatter light Scatter blue better than red Reflected light from objects See objects © Andrew Newbound 2013
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Colour © Andrew Newbound 2013 Red Orange Yellow Green Blue Indigo
Violet © Andrew Newbound 2013
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Colours of Light © Andrew Newbound 2013
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Natural Resources Topic 6 © Andrew Newbound 2013
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Energy Allows things to happen & change Cannot be seen
Can never be used and destroyed Changes into other types of energy Most can’t be used again Energy efficiency Percentage of total energy that is used & not used Joules (J) Unit of measurement for energy 1000J=1 kilojoule © Andrew Newbound 2013
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Alternative Energy Sources
Fossil fuels Non-renewable Will be used up in the future Non-renewable fuels Cause many environmental problems Renewable energy sources Can be made again in the environment Sustainable Can be used in the future without problems: Economic Environmental Social © Andrew Newbound 2013
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Alternative Energy Sources
Don’t cause pollution Cheap Readily available Renewable © Andrew Newbound 2013
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Types of Alternative Energy
Advantages Disadvantages Hydroelectricity More rainwater is replenished in the dam Only sometimes suitable Disrupts the environment Tidal energy Works with environment Expensive Only some places are suitable Wave energy Works with the environment Cost Finding locations Wind energy Small power output per generator Solar Amount of suitable sites Geothermal Uses unutilised energy Very limited locations Biomass Can make more valuable fuels © Andrew Newbound 2013
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Fuels of the Future © Andrew Newbound 2013 Ethanol
Fermentation of plant matter Hydrogen Electrolysis of water Biomass Methane & bacterial decay of animal matter © Andrew Newbound 2013
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Greenhouse Earth Greenhouse gases Greenhouse effect
Gases which trap some of the energy leaving the Earth’s surface E.g. Carbon Dioxide Methane Chlorofluorocarbons (CFCs) Nitrogen oxides Greenhouse effect Heat from earth radiated towards surface Supports life © Andrew Newbound 2013
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Greenhouse Earth Enhanced greenhouse effect
Burning of fossil fuels more greenhouse gases Increase in amount of energy trapped in the atmosphere Rise in temp of atmosphere Clearing forests For agriculture, paper production © Andrew Newbound 2013
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Sources of Greenhouse Gases
Main Sources Carbon dioxide Burning of coal Burning of gas Burning of oil Methane Livestock E.g. cows Rice paddies Mining CFCs Aerosols Refrigerants in fridges and air-cons Production of plastic foal Dry cleaning Nitrous oxides Fertilisers Burning of fossil fuels Especially petrol © Andrew Newbound 2013
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⇒𝐶𝑎𝑟𝑏𝑜𝑛 𝐷𝑖𝑜𝑥𝑖𝑑𝑒 +𝑊𝑎𝑡𝑒𝑟
Burning Fossil Fuels ⇒𝐶𝑎𝑟𝑏𝑜𝑛 𝐷𝑖𝑜𝑥𝑖𝑑𝑒 +𝑊𝑎𝑡𝑒𝑟 © Andrew Newbound 2013
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Nuclear Energy Contained inside nucleus of atoms Fission
Splitting an atom into 2 Protons and neutrons join together at random Make 2 new atoms Not correct balance between neutrons, protons and binding energy Eject excess ‘radioactive’ © Andrew Newbound 2013
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Nuclear Energy Radioactive atoms Fusion Unstable
Decay into stable atoms Excess energy/subatomic particles are ejected from nucleus Can damage surrounding cells Fusion Joining atoms of hydrogen to make helium Produces huge amounts of energy No radioactive waste products © Andrew Newbound 2013
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Nuclear Energy Chain reaction Nuclear medicine
Neutrons being thrown from an atom during fission triggers more fission Nuclear medicine Radioactive chemicals to view tumours etc. inside the body Nuclear radiation can cause tumours Makes cells change Including DNA © Andrew Newbound 2013
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Chain Reaction © Andrew Newbound 2013
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Power from the nucleus Fission of a uranium-235 atom produces
A krypton atom Barium atom 3 neutrons Gamma rays Boron can absorb neutrons Used in nuclear power stations Control rods Change speed of reaction © Andrew Newbound 2013
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Power from the Nucleus Nuclear power station Heat from reaction
Changes water to steam Steam drives turbines Turbines drive generators Generators produce electricity © Andrew Newbound 2013
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Radioactivity Carbon-14 is radioactive
Nucleus is unstable due to extra neutrons Compared to stable carbon-12 © Andrew Newbound 2013
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Types of Radiation © Andrew Newbound 2013 Alpha Particles
2 protons and 2 neutrons Like helium nucleus Shoot out at high speed but slow down in air Paper and skin can stop them © Andrew Newbound 2013
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Types of Radiation © Andrew Newbound 2013 Beta Particles
Fast electrons Neutron breaks up forming a proton and an electron Pass through thin sheets of metal Get through skin 20/30cm in air © Andrew Newbound 2013
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Types of Radiation © Andrew Newbound 2013 Gamma rays High energy rays
Through thick sheets of metal Except lead Can pass deep into our bodies © Andrew Newbound 2013
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Radioactivity Geiger counter Half-life Carbon dating Detects radiation
Time taken for ½ of radioactive atoms in a sample to decay Carbon dating Carbon atoms constantly being taken in when alive Including carbon-14 Decay slowly when die Age can be worked out © Andrew Newbound 2013
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Elements in the Earth’s crust
© Andrew Newbound 2013
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Earth Resources Resource Metals Ore
Useful material/substance obtained from the Earth Metals Obtained from minerals called ores Ore Economically important mineral Useful quantities of a metal Most are impure Mixed with sand + other worthless materials Gangue © Andrew Newbound 2013
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Earth Resources Concentrate Refining Concentrated metal ore
Carried to smelter Refined Through heating Refining Purification of metals Electrolysis Electrical energy used to deposit pure metal onto large electrodes © Andrew Newbound 2013
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Earth Resources Froth flotation
Method used to extract metals from impure minerals Make metals stick to kerosene bubbles © Andrew Newbound 2013
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New Materials Stone age Ancient Egyptians Iron Age
People used stone tools and implements Ancient Egyptians 1st people to smelt copper Iron Age Began: BC Tech used to extract iron was developed Iron tools were widely used © Andrew Newbound 2013
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New Materials Industrial Revolution Ceramics & plastics 1750-1800
Small workshops factories Hand made machine made Energy No longer animals + moving water Now steam engines burning coal Ceramics & plastics Replacing metals in many uses Creating new uses © Andrew Newbound 2013
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New Materials New materials from biological molecules
Ages started at diff times in diff places Availability of resources was diff New plastics Kevlar Polycarbonate Terram © Andrew Newbound 2013
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New Materials Iron Age Bronze Age Copper Age Stone age 1500-1000BC
yrs ago Stone age © Andrew Newbound 2013
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