Presentation on theme: "Chapter 1 Honors Biology Part II Notes. II. Unifying Themes of Biology 1. The Unity of life’s diversity: - Organization & Cell Theory - The Genetic Code."— Presentation transcript:
Chapter 1 Honors Biology Part II Notes
II. Unifying Themes of Biology 1. The Unity of life’s diversity: - Organization & Cell Theory - The Genetic Code (DNA) & Classification 2. Evolution: - Charles Darwin, Natural Selection, - Adaptations 3. Interdependence: - Relationships between living things - The Environment & Ecology
Themes of Biology 1. Diversity and unity of life a)there are millions of species of organisms b)Diversity = Differences
But how is all of life unified? All life is organized: –Made of cells All life has DNA: –The genetic code DNA **all life has hereditary information in DNA –Its is found in the cell’s nucleus –It is identical in all cells of an organism
Cells represent Unity because they are features that all organisms have in common. List a few things all these types of cells have in common.
Myth Busters: Is dust really mostly made up of human skin ? The myth household dust is mostly human skin; 70, 80 or 99 per cent! The "truth“ No evidence shows dust is mostly made up of any one ingredient; up of any one ingredient; rather, it is a potpourri of everything that is likely to be drifting around your house – skin cells, dust mites and their feces, cat dander, face powder, cigar ash, soil, pollen, insect excreta, and general industrial pollution Dust mites
DNA- all cells have DNA DNA is a large macromolecule that stores hereditary information DNA is short for Deoxyribonucleic acid -–DNA is short for Deoxyribonucleic acid - Double helix shape - Double helix shape is formed by nitrogenous base pairs attached to a sugar- phosphate backbone. –It’s twisted ladder shape (double helix) is about 3 feet long in a single cell
“Unity of Life’s Diversity” Taxonomy: the classification of organisms Tree of Life: shows that all living things have descended with modification from a single common ancestor
Phylogenic Tree Shows relationships: between 3 Domains & 6 Kingdoms
Taxonomic Classification: 3 domains: Bacteria, Archaea, and Eukarya. 6 Kingdoms: Archaea, Bacteria, Protista, Fungi, Plantae, and Animalia. Further divided into smaller Taxonomic groups: –phyla –class –order –family –genus –species
3 Domains 1.Archaea -Prokaryotic cells (unicellular) -little understood, recently discovered life -probably oldest cells & found in extreme environments KINGDOM– Archaea 2.Bacteria = Prokaryotic cells (unicellular) -all the common bacteria, both good & bad -KINGDOM— Bacteria 3. Eukarya = Eukaryotic cells (have a nucleus) There are four kingdoms in Eukarya * Protista* Fungi * Plantae* Animalia
The Tree of Life : -The relationships by ancestry among organisms Three domains -2 are prokaryotic -1 Eukaryotic
2. Evolution 1.Theory that organisms change over time, the driving force is the environment. 2.Natural Selection - process by which adaptation is passed on to the next generation for best survival. 3.Adaptations- -are favorable traits -Ex.- cactus plants adapted to desert (2nd Theme in Biology)
Science & Religion- Science & Religion- in answer to your questions: Occasionally, the media may report on the “conflict” between religion & science- implying that one must “choose” – or that science has “replaced” religion. For most there is no conflict! Many famous scientists were Christians who used their Judeo-Christian belief in a rational God as the foundation for their study. Even Evolution is NOT contrary to personal faith.
Charles Darwin- English naturalist who presented compelling evidence that all species of life have evolved over time from common ancestors, through the process he called natural selection.
Darwin’s trip around the world on the H.M.S.Beagle, especially the stops in South America & the Galapagos Islands were the basis for his work.
Darwin saw unusual things on his voyage & tried to explain them: Strange Fossils Large tortoises Many kinds of beaks on finches
Summary: 4 Main Parts of Darwin’s Reasoning 1. Overproduction- more offspring are produced than can survive 2. Genetic Variation- within a population, individuals have different traits 3. Struggle to Survive - individuals must compete with each other to exist. 4. Differential Reproduction - Organisms with the best adaptations to environment more likely to survive & reproduce.
Chapter 15 Natural Selection 4 Main Parts of Darwin’s Reasoning
Natural Selection A simple example of Natural Selection -tiny fish may be able to hide under rocks and not get eaten by a predator -next generation has fewer large fish, “ nature ” has selected for smaller fish in that pond
22 the ability of a species to survive in a particular ecological niche, esp. because of alterations of form or behavior brought about through natural selection adaptation
Evolution: Darwin’s Finches
Evolution discuss the ideas that make up the mechanism for evolution- NATURAL SELECTION. For example:
Terms about Structure & Function MorphologyMorphology – the structure and form of an organism AnatomyAnatomy – the branch of morphology that deals with internal structure Structure is almost always related to function. Example- Bird beaks- shape shows how it gets food Biology Terms: Extra Info that you will need to know
3. Interdependence Ecology- How organisms interact with both other organisms & the environment. 1.Biotic Factors – living organisms 2.Abiotic Factors - non-living part of the environment (water, temperature, soil type,etc) 3.Ecosystems - Communities of different living species (Biotic factors)& interact with each other & their non-living environment (Abiotic factors). II. 3 Themes in Biology
Ecology Ecology Is the study of how organisms interact with each other and their physical environment. Environment – everything- biotic & abiotic- surrounding an organism
Energy Relationships Energy Relationships -study how organisms get, use & transfer energy Sun- Source of almost all energy Autotrophs- Organisms that make their own energy (food) ( photosynthesis ) Heterotrophs – Organisms that obtain energy by eating other organisms
Food Chain & Food web in an Antarctic Ecosystem All food chains must start with a producer (autotroph)!!! What is the difference between a food chain & a food web?
Note numbers of organisms: Chart: many times more producers than large carnivores
Ecology Levels of Organization ORGANISM - Simplest Level (1 living thing) POPULATION - All the members of the same species - that live in one place at a given time & make-up a breeding group. COMMUNITY- Includes all the interacting populations in one area. ECOSYSTEM - Includes all the living (biotic) & non-living (abiotic) factors in the environment. BIOSPHERE - Thin layer of life around earth.
Levels of Organization
The future: Note that the human population level on planet Earth is now approaching 7 billion individuals. That’s more than five children born every second!
Sustainability: The ability to meet today’s needs without sacrificing the needs of future generations
Science & Society Applied Science- knowledge from biological science can be used to improve human life Bioethics – The study of what is right or wrong as it applies to biological concerns. Biotechnology- technology based on biology, especially when used in agriculture, food science, and medicine –genetic engineering, & DNA Technology- making new forms of life by transferring genes from one organism into another- like inserting gene for enzyme Chymosin -from the stomach of calves into the DNA of both bacteria and yeasts-
36 application of scientific research to society's needs and problems technology
Biotechnology: Biotechnology: Genetically engineered cheese – cheese is now cheaply made - with genetically modified yeast chymosin, (an enzyme which curdles milk, found in calves, who drink milk, but not in normal yeast!)
Genetic Medical Applications Making medicine- until recently- medicine had to be collected from plants or made from chemicals. Now can make body substances like human blood clotting factors, insulin, vaccines & (HGH) HumanGrowthHormone with GM bacteria. Making body parts- may be able to clone cells & make new organs so that no rejection occurs. May be able to grow new human liver in another organism like a pig. May also be able to screen for diseases, create “designer babies”, cure cancer.
Gene Therapy Example: replace or repair faulty gene for cystic fibrosis. Insert a copy of good gene from healthy person into virus. Infect patient’s lungs with virus, virus delivers good gene. Now patient can make the right protein to stop accumulation of mucus & can breathe normally. Imagine being this mother of child with CF, Daily you must massage & loose mucus. Any cold could overwhelm & cause death. Now imagine what gene therapy represents.
Examples: Featherless chicken a controversial featherless chicken which they say is faster growing. will not need to be plucked, saving money in processing plants. they would not be suitable for cooler countries,but OK in hot climates There was a rumor that KFC uses these already but it is not true.
Fishy Strawberries Flounder is a fish that can withstand icy cold temperatures. Scientists took the gene in the fish that Produces an antifreeze & inserted it into a plasmid of a bacterium The bacterium infected the strawberry & the flounder antifreeze gene entered the strawberry’s DNA The new GM strawberry cells are grown Into new plants that have strawberries which make a protein that keeps the fruit from frost damage.
GM foods- Golden Rice Golden Rice is part of the solution to world hunger & malnutrition. Biofortified rice may alleviate life-threatening micronutrient deficiencies in developing countries -(decrease starvation) -Biofortified rice may alleviate life-threatening micronutrient deficiencies in developing countries -(decrease starvation) - Genetically modified- gene for provitamin A (β-carotene) is inserted into rice genome. - Genetically modified- gene for provitamin A (β-carotene), is inserted into rice genome.
All living things have the same genetic building blocks DNA- deoxyribonucleic acid has 4 nitrogenous bases which make up the “alphabet” for the genetic code. SO- the same sequence of DNA (gene) codes for an enzyme, a protein or other molecule no matter which organism that gene is in. That is the basis for Gene technology
Biotechnology There is currently much debate among scientists, politicians & environmentalist about the safety & quality of genetically modified products, especially foods. It is very likely that you have already eaten multiple products that were produced with biotechnology and/or DNA technology
III. The Study of Biology A. The Scientific Method Steps: 1. Observation 2. Hypothesis 3. Prediction 4. Experiment 5. Data Analysis/ Conclusions 6. Communication/ Verification B. Evaluating Bias- at times, scientists have conflicts of interest. A scientist’s goal should be finding facts, not support of government agency agenda or the desired results of a pharmaceutical company.
Experiment terms Remember: Experiment terms –Control group provides a normal standard against which we compare results of the experimental group. –Experimental group is identical to the control group except for one factor. –Variables: factors that change –Theory - a set of related hypotheses confirmed to be true many times –An advantage of the scientific method is that it is unbiased & repeatable.
Controlled Experiment A control group provides a normal standard against which the biologist can compare results with the experimental group An experimental group is identical to the control group except for one factor, the independent or manipulated variable. *** Other variables that may affect the outcome of the experiment should be the same in both control and experimental groups
Implementing the Scientific Method The scientific method is used to solve problems It is not an exact process No Experiment is a Failure If negative results occur, a scientist can show that a certain hypothesis is not valid An experiment can be successful even if it shows that a hypothesis is not consistent with observations
Communicating Ideas Publishing or presenting experimental results Four Parts of a Paper –Introduction – states problem and hypothesis to be investigated –Materials and Methods – what was used and how –Results – Findings using graphs, tables, charts –Discussion – conclusion, error sources, significance of experiment, and future needs are discussed Paper submitted for Peer Review –Errors, conflict of interest and honesty is checked –Allows science a method to self-correct mistakes
Read the following passage and answer these questions with a partner: An environmental engineering firm has been called to determine why fish are dying in a local stream. A red liquid was observed leaking from a mine that while fish were dead downstream, there were no dead fish upstream from the mine. 1.Give a possible hypothesis. 2.Design an experiment to test your hypothesis. 3.What is the control in your experiment. 4.List dependent & independent variables.
IV. Tools & Techniques A. Microscopes 1. Types of Microscopes *Compound light microscope - shines light through a specimen (must have thin slice of object) -uses 2 lens to magnify image. *Electron microscope -SEM ( scanning electron microscope) -TEM (transmission electron microscope) 2. The parts of the Microscope- see hand out
Compound microscopes Used to magnify thin slices of specimens
Magnification with each lens TOTAL MAGNIFICATION= low power magnification X eye piece magnification The eyepiece is 10X Low power is 4X Other lens may vary- usually - 10X - 40X
Microscope Use: Carry the microscope with 2 hands- By the “arm” & one hand under the base Look through eyepiece & keep both eyes open Place the slide that you want to view over the aperture and gently move the stage clips over top of the slide to hold it into place. ALWAYS begin use & focus with the *M icroscope on LOW Power (4X)!!!! * Make sure the stage is all the way down.!!!!! Always Begin focusing with the coarse adjustment
Light Microscopes –The eyepiece magnifies the image. –The objective lens enlarges the specimen. –The stage is a platform that supports slides with specimens. –The light source is a light bulb that provides light for viewing images.
Magnification & Resolution –Magnification is the increase of an object’s apparent size. –Resolution is the power to show details clearly in an image.
Figure 1. Relative Size of Microbes. E.M. refers to the Electron Microscope.
Object Size and Magnifying Power of Microscopes
B. Other tools Centrifuge- spinning separation of materials in a liquid that have different densities Autoclave – heating chamber to disinfect Chromatography - is any technique that separates different substances based on their chemical or physical properties Electrophoresis - is a technique for separating particles that have an electrical charge. Spectrophotometer -determines what a substance is by measuring the amount of each wavelength of light absorbed by the sample. Computers are one of the most important tools used in biology studies.
Electron Microscopes –Scanning electron microscopes pass a beam of electrons over the specimen’s surface for better viewing the external surface of a specimen. –Transmission electron microscopes transmit a beam of electrons through a thinly sliced specimen for better viewing the internal structures of a specimen.
C. Units of Measure SI Units –Scientists use a single, standard system of measurement, called the metric system. The official name of the metric system is Système International d’Unités or SI.
The Metric System The metric system is also called the International System of Units or SI It is a single unified system that is used in nearly every country in the world. This includes the scientific community The English system uses feet, inches, pounds, and quarts.
Prefixes of the Metric System Ttera trillion Ggiga billion Mmega million kkilo thousand h hecto* hundred dadeka* ten BASE Unit Meter- Liter- Gram one ddeci*10 tenth ccenti*10 hundredth mmilli10 thousandth µmicro10 millionth nnano10 billionth ppico10 trillionth