1. Introduction to Biology
The Study of Life

2. What is Science?
Science is an organized way of gathering and analyzing evidence about the world.
There are universal laws that apply to all objects in the universe, small or large, living or nonliving.

3. The goal of science is to
Provide explanations for events in
nature
To understand patterns
To make useful predictions

4. Science never stands still. New discoveries
raise new questions.
Science aims for the best understanding that current methods can reveal.

5. Science begins with making observations which involve noticing and describing events.
Scientists use the information they gather to make inferences. These are logical interpretations based on prior knowledge.

6. The Scientific Method Steps: 1. Observe and ask questions
2. Infer and form a hypothesis
3. Design a controlled experiment
a. controlled variables-may be deliberately changed. These are called the independent variable or manipulated variable.
b. The variable that responds to the independent variable is called the dependent or responding variable

7. c. the control group is carried out under normal conditions d
c. the control group is carried out under normal conditions d. The experimental group is done the same as the control group except for the dependent variable

8. The information we gather is called data There are two main types:
Quantitative which is expressed in numbers
Qualitative which involves descriptions and can’t be counted.
Data can then represented in some visual way such as a chart, graph or diagram

9. Graphing Rules: Independent variable is known or predetermined.
it is placed on the bottom of the graph
Dependent variable is the unknown
it is placed on the side of the graph

10. An understanding of science is important in making intelligent decisions about life.
Science can make recommendations but
society makes the final decisions.

11. follow the teacher and lab handout instructions exactly!
Lab Safety
The most important rule in a lab is:
follow the teacher and lab handout instructions exactly!
If in doubt, ask questions.

12. Class labs: No goofing around Keep glassware from edges of tables
No food or drink in lab area
Always clean up your own area

13. Lab tools
1. Dissection tray-pan for holding animal while dissecting. Filled with wax to stick pins in.

14. 2. Eye dropper-used for small amounts of liquid
3. Triple beam balance-determines the mass of an object

15. 4. Metric ruler-measures length of objects 5
4. Metric ruler-measures length of objects 5. Dissection scissors-for cutting, have a short blade

16. 6. Probe-for probing inside animal
7. Forceps-picking up small items
8. Scalpel-cutting

17. 9. Petri dish-circular dish for growing bacteria

18. 10. Test tube rack-holds several test tubes upright
11. Test tube-for growing bacteria

19. 12. Microscope-magnifies very small objects

20. 13. Slide-rectangle shaped glass for putting object on to view under microscope 14. Cover slip-square of thin glass to spread out object so light can go through it

21. 15. hand lens-magnifying objects that are too big for a microscope.

22. 16. Beaker-holding materials, mixing, heating--never for measuring 17
16. Beaker-holding materials, mixing, heating--never for measuring 17. Graduated cylinder-accurately measures liquids

23. 18. Thermometer-measures heat in an object

24. 19. Goggles-protects eyes from splashes from
harmful chemicals
20. Bunsen burner-for heating materials

25. The Metric System Most experiments include measurements.
(quantitative)
Experiments must be able to be repeated so scientists use a common measuring system called the metric system.

26. Basic units of measuring:
mass-grams

27. Length-meter

28. Volume-liter

29. Temperature Scales Fahrenheit Celsius Water boils Body temp Room temp
Water freezes

30. Prefixes for units: Milli = .001 Centi = .01 Deci = .1 1 Deka = 10
Hecto = 100
Kilo =

31. Rule to change from one to another:
When you go up you multiply by 10 and move the decimal to the right.
When you go down you divide by 10 and move the decimal to the left.

32. Characteristics of living things:
Made up of cells
Able to reproduce
Based on the genetic code-DNA
Grow and develop
Obtain and use energy (Metabolism)
Respond to their environment
Maintain a stable environment (homeostasis)
Groups of living things change over time (evolve)