1. 7th Science
Chapter 1

2. Section 1: Getting Started/What is Life?
Types of Science
1. Earth science – atmosphere, solar system, geology (rock layers, volcanoes, etc.)
2. Life science – plants, animals, other living things
3. Physical science – matter and energy – chemistry and physics

3. Characteristics of Life
All living things have cellular organization, contain similar chemicals, use energy, respond to their surroundings, grow and develop, and reproduce
Living things arise from other living things through reproduction
All living things must satisfy their basic needs for food, water, living space, and stable internal conditions(homeostasis).

4. Characterisitcs of Life
Living things = organisms
Cell= basic unit of structure and function in an organism
Aall organisms are composed of at least one cell (unicellular) some are many cells (multicellular).
Cells are made of chemicals and the most abundant chemical is water.
Carbohydrates are a cell’s main source of energy

5. Proteins and Lipids are building materials for cells
Nucleic Acids (DNA /RNA) are the genetic material of the cell
Nucleic Acids are the chemical instructions that cells meed to carry out the functions of life
Metabolism= combination of chemical reactions through which an organism builds up or breaks down materials

6. Stimulus= Achange in an organism’s environment that causes the organism to react
Response= An action (reaction) or a change in behavior due to a stimulus
Growth & Development
Growth= process of becoming larger
Development = is a process of change that occurs during an organism’s life

7. Reproduction
Asexual= involves only one parent and produces offspring that are identical to the parent (cloning)(Budding) (Fragmentation)(Binary Fission)
Sexual= involves two parents and combines their genetic material to produce a new organism that differs from both parents.

8. – Living Things
An organism is any living thing, no matter how big or small
Examples of nonliving things: water, air, sun, clouds
Living things are organized
Cell – smallest unit
Tissues
Organ
Organ system (digestive, circulatory)
Organism

9. Some organisms are made up of only one cell, some have many cells.
Living things react to their surroundings.
Anything that causes some change in an organism is called a stimulus.
The reaction to a stimulus is called a response.
Stimuli is more than one stimulus

10. Homeostasis – ability to keep a balance within the body no matter what conditions are outside the body.
Living things use energy
Plant – use the Sun’s energy to make their own food (photosynthesis)
Humans – eating food

11. Living things grow and develop
Increase in the number and size of their cells.
Living things reproduce
Without reproduction the species would become extinct.
Living things need a proper place to live.
Raw materials – food, drink, oxygen

12. Where Do Living Things Come From?
Biogenesis = Current Belief.
Living things arise from other living things through reproduction (asexual or sexual)
Spontaneous Generation= Original belief. Mistaken idea that living things can arise from nonliving sources.

13. Support of Biogenesis Fransico Redi – still non believers
Louis Pasteur- Finally disproved spontaneous generation

14. Fransico Redi’s Experiment
Showed that maggots laid eggs that developed into flies
Controlled experiment
Series of tests that are identical in all ways except for ONE factor (experimental factor)
Redi’s = Type of covering over the jars- (experimental factor) only change in his experiment

15. Pasteur’s Experiment
Developed the Swan neck flask ( experimental factor)
Pasteur = worked with bacteria
This was the experiment that finally disproved spontaneous generation

16. Solving Problems
Scientific Method
-State the Problem
-Gather Information
5 senses – taste, touch, smell, sight, hearing
Make observations
-Form a hypothesis
A prediction about what you think will happen

17. -Test hypothesis with an experiment
You can only change one variable at a time!
-Analyze data
Set up charts, graphs, tables
-Draw Conclusions
Logical answer based on observations, data, and analysis
Report Results
Communication with other scientists

18. Measuring with Scientific Units
Scientists use the SI system and the Metric system (based on units of 10).
Length – meter (m)
Volume – liter (L), centimeter cubed (cm3)
Mass – gram (g) – Kilogram (Kg- SI system
Temperature = Kelvin (SI) Celsius (Metric)
Mass and Weight are different b/c weight measures the force of gravity on an object

19. Safety
Most important safety rule is ask your teacher before beginning anything.

20. What Do Things Need to Survive?
Basic Needs: food, water, living space, and a stable internal condition (homeostasis)
FOOD:
Autotroph = Organisims that can make their own food (photosynthesis or chemosynthesis)
Heterotroph= Organism that cannot make its own food

21. WATER
All living things need water
Ability to dissolve more chemicals than any other substance on Earth.
Apx. 90% of the liquid part of our blood is water

22. Classification Section 2
Aristotle – was one of the first people to classify organisms
Plant or Animal
Linnaeus – simplified the system
Still use Linnaeus’s system today
Binomial Nomenclature – two-word name used to classify living things
It minimizes confusion among scientists
System provides information about the species
Taxonomy= Scientific study of how living things are classified

23. Biologists find taxonomy useful b/c this scientific study gives them musch information about an organism based on its classification
Each genus of organisms contains noe or more species

24. Classification Domains - Broadest Kingdoms Phylum Class Order Family
Genus
Species or specific epitaph – Most Specific

25. Classification Based in LATIN
Two Words ( Genus + Species or specific name)
Capitalize ONLY the FIRST word – Genus)
Second word is the Species (Not Capitalized)
Written in Italics or Underlined
Scientific name for humans = Homo sapien
Scientific name for wolf – Canus lupus

26. An advantage of our scientific naming system is that biologists can communicate regardless of their native languages. Minimizes confusion

27. Scientific names prevent confusion.
Two different organisms can NOT have the same scientific name but they might have the same common name.
The easiest and most efficient field guide to use to identify an organism would be a dichotomous key.
The dichotomous key uses TWO paired descriptions at each step.
Taxonmic Keys- help to determine the identity of organisms

28. The dichotomous key has three basic functions
Avoids errors in communication
It classifies organisms with similar evolutionary histories together.
It gives descriptive information

29. Classification divisions with in the domains
Kingdom
Phylum ( Division- Plants)
Class
Order
Family
Genus
Species - most inclusive / most similar

30. Each level of classification is based on SHARED characteristics
Family is made up of similar Order
Class is made up of similar Phylum
Species is made up of similar Genus
Etc..
Broadest group – Domain
Most Inclusive – Species
Species - Organisms that are similar in structure and form and successfully reproduce among themselves.

31. The DOMAINS and Six Kingdoms
The classification system most commonly used today separates organisms into six (6) Kingdoms
Each level of classification contains all organisms that share the same characteristics

32. 3 Domains
Domain Bacteria
Domain Archae
Domain Eukarya

33. Classification
Characteristics used to place an organism into a specific Kingdom
Autotroph or Heterotroph
Prokaryote or Eukaryote
Body Form
Complex Tissues

34. 6 - Kingdoms Archaebacteria- Domain Archae Eubacteria- Domain Bacteria
Protista-Domain Eukarya
Fungi-Domain Eukarya
Plantae-Domain Eukarya
Animalia-Domain Eukarya

35. Characteristics -Kingdoms
Cell Type - Prokaryote or Eukaryote
Body Form - Unicellular/ Multicellular /Both
Food Getting - Heterotrophs / Autotrophs
Complex organ systems - Yes / No

36. Cell Type Prokaryote – No internal membrane bound organelles
- No Nucleus
Eukaryote – Has internal membrane bound organelles
Archaebacteria - Proraryote
Eubacteria - Prokaryote
Protista – Eukaryote
Fungi - Eukaryote
Plantae - Eukaryote
Animalia - Eukaryote

37. Evolution and Classification
Species with similar evolutionary histories are classified more closely together
Classifies organisms by traits and evolutionary histories
By comparing body structures a scientists can get information about the evolutionary history of a species
Evolution- Process of change over time
Darwin- Natural Selection
Shared Derived Characteristic- a trait that a common ancestor of a group had and passed it on to its descendants
Branching Tree or Cladogram- shows probable evolutionary relationships. Organisms are grouped according to shared derived characteristics.

38. MODERN SYSTEM of CLASSIFICATION
Charles Darwin
Theory of Natural Selection
Commonly called survival of the fittest

39. Can an organisim belong to the same family but to different classes
Can an organisim belong to the same family but to different classes? Explain
No, A family is a sub group of one order, and an order is a sub group of one class. Therefore, any two organisms that belong to the same family MUST also belong to the same class
Kindom-Phylum-Class-Order-Family-Genus-Species

40. Why is the Protista Kingdom sometimes called the “odds and ends” or ‘Junk” Kingdom?
Its members differ so much from one another and they do not fit into any of the other kingdoms. Some are autotrops and also heterotrophs and some are unicellular and multicellular

41. Computers use energy and respond to stimuli, such as commands from the user, Why, then are computers not considered living?
Computers do not have all the characteristics of living things. They are not composed of cells. They can not reproduce. They do not grow and develop.

42. What are Linnaeus’ two major contributions to taxonomy?
1. Binomial Nomenclature
2. Grouping organisims based on their observable or structural characteristics