1. Biology: Themes in the Study of Life
Chapter 1

2. Life’s levels of organization define the scope of biology
Emergent properties
Life emerges at the level of the ________

3. Cells are the Structural and Functional Units of Life
Two distinct groups of cells exist
Prokaryotic cells
lack membrane bound organelles
simple and small, range in size from 1-10 µm
ex. bacteria
Eukaryotic cells
Have membrane bound organelles;
Can be a single cell, most are multicellular; µm
ex’s. plants, animals, fungi and protists

4. Prokaryotic cell
Eukaryotic cell
DNA
(no nucleus)
Membrane
Nucleus
(contains DNA)
Organelles

5. Cells are the Structural and Functional Units of Life
Form generally fits function
By studying a biological structure, you can determine what it does and how it works.

6. Living Organisms Interact with their Environments
To be successful, an ecosystem must recycle chemicals necessary for life & move energy through the ecosystem
Biotic and Abiotic components must interact to accomplish this
Biotic components
Producers :Photosynthetic organisms that provide food for a typical ecosystem
Consumers: Eat plants (or animals that profit from plants)
Abiotic components
Chemicals & nutrients required for life
Ex’s. O2, CO2, water, visible light, etc.

7. Producers Consumers Ecosystem Sunlight Cycling of chemical nutrients
Heat
Chemical energy
Consumers
Figure 1.2 The cycling of nutrients and flow of energy in an ecosystem.
Heat

8. EVOLUTION, THE CORE THEME OF BIOLOGY

9. The Unity of Life: All forms of life Have Common Features
DNA is the genetic (hereditary) material of all cells
A gene is a discrete unit of DNA
Diversity of life results from differences in the sequence of chemical bases in DNA
The chemical structure of DNA accounts for its function

11. Diversity Results from Differences in DNA Sequence

12. The Unity of Life All living things share common properties Order
Regulation
Growth and development
Energy processing
Response to the environment
Reproduction
Evolutionary adaptation

13. (3) Growth and development (4) Energy processing
(1) Order
(2) Regulation
(3) Growth and development
(4) Energy processing
Figure 1.4B Some important properties of life.
(5) Response to the environment
(6) Reproduction
(7) Evolutionary adaptation

14. The Diversity of Life Can be Arranged Into Three Large Domains
Domain Bacteria—prokaryotic, mostly unicellular, microscopic
Domain Archaea—prokaryotic, mostly unicellular, microscopic
oldest and most extreme
Domain Eukarya—eukaryotic cells, uni/multicellular with membrane bound organelles

15. Domain Eukarya Includes Four Kingdoms: K. Animalia, K. Plantae, K
Domain Eukarya Includes Four Kingdoms: K. Animalia, K. Plantae, K. Fungi, K. Protista
K. Protista
K. Plantae
K. Fungi
K. Animalia

16. Evolution Explains the Unity and Diversity of Life
In 1859, Charles Darwin published On the Origin of Species by Means of Natural Selection
The book accomplished two things
Presented evidence to support evolution
Proposed that the mechanism for evolution is natural selection

17. Evolution Explains the Unity and Diversity of Life
Natural selection was inferred by connecting two observations
Individuals within a population inherit different characteristics and vary from other individuals
(A population is varied!!!)
A population can produce far more offspring than the environment can support; those individuals that have inherited traits best suited for the environment will survive to produce offspring of their own

18. Population with varied inherited traits1
Population with varied inherited traits 2
Elimination of individuals with certain traits
Figure 1.6B An example of natural selection in action. 3
Reproduction of survivors

19. Evolution Explains the Unity and Diversity of Life
Natural selection is an editing mechanism
It results from exposure of heritable variations to environmental factors that favor some individuals over others
Over time this results in evolution of new species adapted to particular environments

20. Killer whale Pangolin Pangolin
Figure 1.6C Examples of adaptations to different environments.
Killer whale
Pangolin

21. THE PROCESS OF SCIENCE

22. Scientists Use Two Main Approaches to Learn About Nature
Two approaches are used to understand natural causes for natural phenomena
Discovery science—uses verifiable observations and measurements to describe science
Hypothesis-based science—uses the data from discovery science to explain science.
This requires proposing and testing of hypotheses

23. Scientists Use Two Main Approaches to Learn About Nature
What is the difference between a theory and a hypothesis?
A hypothesis is a proposed explanation for a set of observations
A theory is supported by a large and usually growing body of evidence

24. Hypothesis-Based Science Poses and Tests Hypotheses
We solve everyday problems by using hypotheses
An example would be the reasoning we use to answer the question, “Why doesn’t the flashlight work?”
Using deductive reasoning we realize that the problem is either the (1) bulb or (2) batteries.
The hypothesis must be testable and falsifiable
A hypothesis must be testable—find ways to check the validity of the idea. A hypothesis must also be falsifiable—find ways to reveal whether such an idea is actually not true.
Teaching Tips
1. Consider using a laboratory exercise to have your students plan and perhaps conduct investigations using discovery science and/or investigations using a hypothesis-driven approach. Emphasize the processes and not the significance of the questions. Students can conduct descriptive surveys of student behavior (use of pens or pencils for taking notes, use of backpacks) or test hypotheses using controlled trials. Students will need some supervision and advice while planning and conducting their experiments.
2. Consider presenting your class with descriptions of several scientific investigations that you have written or found described in the media. Edit or include numerous examples of improper methodology (small sample size, several variables existing between the control and experimental groups, failure to specifically test the hypothesis, etc.). Let small groups or individuals analyze the experiments in class to identify the flaws. This critical analysis allows students the opportunity to suggest the characteristics of good investigations in class.
3. Have your students explain why a coordinated conspiracy promoting a specific idea in science is unlikely to succeed. Have your students describe aspects of science that would check fraudulent or erroneous claims and/or political efforts.

25. Test falsifies hypothesis
Observations
Question
Hypothesis #1:
Dead batteries
Hypothesis #2:
Burned-out bulb
Prediction:
Replacing batteries
will fix problem
Prediction:
Replacing bulb
will fix problem
Figure 1.8A An example of hypothesis-based science.
Test prediction
Test prediction
Test falsifies hypothesis
Test does not falsify hypothesis