1. Biological Principles

2. Biology – Science of life Greek – “bios” = life “logos” = study of Biology Botany Zoology (study of plants) (study of animals)

3. How do you tell if something is living?
All living things are made of cells.
All living things are highly organized.
All living things use energy.
All living things are able to maintain homeostasis.
All living things grow as a result of cell division.
All living things reproduce.

4. Nine Life Activities found in all living organisms:
Nutrition – getting food
Digestion – chemical changing of food into a form which is usable
Absorption – getting water, ions, and food from the environment
Biosynthesis (assimilation) – using food to make new protoplasm
Respiration – process by which food is oxidized to release energy
Excretion – separation of waste products
Secretion – manufacture of special chemicals (hormones and vitamins) which affect other cells
Response – change due to stimuli; varies
Reproduction- cells dividing to produce new cells

5. Metabolism – the sum total of all chemical reactions which build up and tear down complex molecules

6. Scientific Method Goal of Science – investigate and understand nature
Science is an organized use of evidence to learn about the natural world
Science starts with observations – information gathered using the senses (data)

7. 2 Forms of gathering data
Quantitative – uses numbers (counting and measuring)
Qualitative – uses the senses
Inferences – interpretation based on what you already know

8. Quantitative Vs. Qualitative (data)
Describing the color of a sample
Describing the smell of a particular sample
Touching an object to determine if it is smooth or rough
*Usually includes an adjective
Using a ruler to measure how much a plant has grown
Using a thermometer to obtain the temperature of a sample
Estimating the population of polar bears in the Arctic
*Always includes a number (and unit)

9. Variables Variable – what is being manipulated
can only test one variable at a time
Two types of variables in experiments:
Independent Variable
Dependent Variable

10. Independent vs. Dependent Variables
The variable directly affected by the independent variable
Placed on the Y-axis
Ex. Growth rate, acceleration, weight change
Independent
The variable that can be controlled by the experimenter (“I change”)
Placed on the X-axis
Ex. Time, depth, temperature

11. Graphing

12. Scientific Method
A logical, organized method of study – used to establish scientific principles
The beginning of the scientific method begins with an observation

13. 5 Steps to the Scientific Method
State the problem
Make an educated guess, hypothesis, about the answer based on what is known (if-then); testable
Design and conduct a controlled experiment to test the hypothesis
a. control group – under normal conditions; variable not changed b. experimental group- exposed to the variable 4. Analyze the data collected 5. State the conclusion
After much testing, the hypothesis may
become a scientific principle or a theory.

14. Experiment 1
A student wants to determine the effect of differing amounts of fertilizer on the growth of ivy. Ivy plants of the same length are planted in the same amount of soil in three identical containers. The containers have the following amounts of fertilizer:
The containers are
placed in front of the
same window.
The length of the ivy is measured every five days, the observations are recorded in a data table.
Container 1
5 mL
Container 2
10 mL
Container 3
no fertilizer

15. Experiment 1 What is the inference?
Identify the experimental group(s).
Identify the control group.
What is the quantitative measurement?
What is the qualitative measurement?
What is the independent variable?
What is the dependent variable?
Make a good hypothesis for this experiment.

16. Experiment 2
A scientist is testing the efficiency of various microwaves by measuring the temperature of water after being heated for one minute at high power.
What is the inference?
Is this a controlled experiment?
What is the quantitative measurement?
What is the independent variable?
What is the dependent variable?

17. The Microscope
Magnification – power to increase an object’s apparent size Resolution – power to show detail clearly Light microscope – uses light Specimen – the object being viewed – must be thin enough to let light through

18. Compound Light Microscope
2 Kinds of lenses 1. ocular (A.K.A. the eyepiece) – magnifies 10X 2. objective – nearest the specimen The degree of magnification is determined by the combined magnification of the lenses. X stands for times

20. How to find total magnification:
Multiply the power of the objective lens by the power of the ocular lens
The powers are usually sketched on the side of the lens

21. Total Magnification 4 10 40 10 10 100 40 10 400 Scan Low High
Objective
Power of
Ocular
Total
Magnification
Scan
Low
High 4 10 40 10 10
100 40 10
400

22. Evolution
Study of how organisms adapt to their changing environment over time
Many different theories
Speciation – introduction of new species resulting from evolution
Important unifying concept in biology

23. Microevolution versus Macroevolution
Small-scale changes
Often can be observed in a lifetime in populations
Does not result in speciation
Macroevolution
Large-scale changes
Often debated
Takes so long, often cannot be observed, so fossil data is used
Results in speciation