Janice Lapsansky
MWF 8-8:50, AH 100
Fall 2007
(no labs this week)
Office: Biology 305
Phone: 650-7337
Email: janice.lapsansky@wwu.edu

• Attend class and lab meetings
• Pre-read
• Use all of the resources available
– print the PPT handouts
• Form study groups
• Plan for enough study time
• Know your preferred learning style(s)
• Record lectures
• Checkout a “ clicker ”

1. E-MAIL the TA (teaching assistant) assigned to the lab you want.
2. Continue to attend lecture.
3. If issued an override, you must register before 5pm on Friday , Oct.
5 th , or you will be charged $40 late fee by the Registrar.

1.
Describe the work of biologists and the method they use to create knowledge about living things.
2.
Differentiate between inductive and deductive reasoning. Which is used more often in biology?
3.
Which of the steps in the scientific process is the most important: observation, hypothesis, or test? Justify your answer.
4.
Create a hypothesis and describe its use to answer an important question in science.
5.
Compare and contrast the levels of organization in biological systems.
6.
Describe the characteristics shared by all living things.
Use these characteristics to distinguish one non-living thing (e.g. a virus or a table) from yourself.
7.
Describe the classification of all living things according to the 5-Kingdom classification scheme.

Why do we study life?
How do we study life?
-- a matter of scale - -
size and time
-- chemistry & physics --
Which ideas & concepts guide biologists?
Oldest known fossil of cyanobacteria.

How do you respond to the following statement?
“Living things are chemical and physical machines.”
Do you tend to have holistic view of life, or do you see life as a sum of its parts?

The world of life shows levels of organization, from the simple to the complex, which extend through: cells (made of?) tissues & organs organisms populations communities ecosystems the biosphere

p. 8
Taxonomy
= the process of naming and classifying organisms
Three Domains:
Archaea
Bacteria
Eukarya
Five Kingdoms:
(see figure on next slide)
Carolus Linnaeus
What is his claim to fame?

1. Levels of organization:
The difference between living and non-living is one of degree, not kind.
What does this mean?
The cell is life’s basic unit of structure and function
What is a cell?
List one example that illustrates the interdependence of structure and function.

What are some of the main similarities & differences between bacteria and human cells?
How is this order maintained, and what does it cost?

Levels of Organization
(plant example) p. 4

(animal example)
(A biome is a group of ecologicallysimilar communities.)

2. Informational Molecules
Some biological molecules contain “code” by virtue of the sequence of their building blocks.
Name the type of molecule that contains the instructions for maintaining the structure and function of an organism.
Name the type of molecule that is made from these instructions.
All forms of life use this same code
Are there other similarities that unify the diversity of life?
Inheritance of traits relies on accurate duplication and transmission of this code to offspring
Can organisms change because they “have to” in order to survive in a challenging environment?
p. 6

3. Emergent Properties
Each level of biological organization has emergent properties that result from the interaction between structure and function
These emergent properties include the range of characteristics we would use to describe life: metabolism, growth and development, homeostasis, reproduction, and evolutionary adaptation .
p. 4

All living things depend directly or indirectly on all other living things for survival
Briefly describe how an organism changes its biotic environment….its abiotic environment.
Describe the flow of energy and raw materials through the
biosphere.
p. 6

What does this figure describe? What else “flows” from producers to consumers to decomposers?

p. 7

p. 6
How and why may an organism change over it’s lifespan?
Animals often exhibit metamorphosis in their development.
Can you explain at least one advantage to this “strategy”?

p. 7
= the maintenance of a dynamic equilibrium
Why does an organism’s internal environment change?
Why is a stable internal environment important to an organism’s survival?
Describe an example.
Most homeostatic mechanisms operate as negative feedback loops.
Draw the components of a basic negative feedback loop.

Which of these groups of organisms have sexual reproduction ? Which can reproduce asexually ?

Who accurately describes an important observation made by Charles Darwin that was pivotal to the development of his concept of evolution?
Alice Populations never produce more offspring than can be supported by the environment
Some individuals possess traits that make them more “fit” in their environment
Barry
Individuals in a population exhibit at least slight differences in their structure and/or function
Cal
Human skin cells look like bacterial cells from mineral hot springs
Dan

p. 10
Evolution is the core theme of biology
– All living organisms are descended from a single common ancestor
• “descent with modification”
– Natural selection is one mechanism of evolution
• In response to gradual, long-term changes in the environment
Evidence indicates that life on Earth first appeared more than 3.5 billion years ago.

True or False.
Evolution creates adaptations.
1. Individuals w/in species are variable.
2. Some variations are passed on to offspring.
3. More offspring are produced than can survive.
4. Survival and reproduction are not random.
Justify your answer.

A human activity that attempts to describe and explain the world
– begins with a question/problem
– one way to acquire knowledge
Can any question be answered by the scientific method?
Can science prove “cause-and-effect” between two variables?
2 basic ways to approach a question:
• inductive reasoning
• deductive reasoning

Inductive Reasoning: generalize from specific observations
(Read the “turkey goodness” story on p. 15)
When is inductive reasoning used in the scientific process?
Deductive Reasoning: propose a model (involving assumptions) that provides a tentative explanation that can be applied to specific situations requires that evidence be collected to test the model and assumptions

Flashlight doesn’t work
Observation(s)
Why doesn’t it work?
Question
Hypothesis A
Batteries are dead
Prediction A
Change batteries…
Hypothesis B
Bulb is broken
Prediction B
Change bulb…
Hypothesis C
Connectors are dirty
Prediction C
Clean connectors…
Test experiments, further observations, simulations

• What important skills are critical to your ability to formulate hypotheses?
• When is more than one hypothesis appropriate in science?
• What is a scientific theory and how is it different from a hypothesis?
When you begin to formulate a question, make sure it is answerable by the scientific method. In other words, the topics of scientific investigation must be:
1) well-defined
2) measurable
3) controllable p. 11

Does smoking cause lung cancer? Does drunk driving cause accidents? Do thin people live longer? You may think you know the answers to some or all of these questions already. On what evidence and/or reasoning do you base your answers?
The collection and analysis of data to determine whether two variables are “linked” are important elements in scientific investigations. Finding variables to be linked (i.e. correlated) suggests the possibility of a cause-and-effect relationship.
The purpose of this small group exercise is to evaluate information based on the results of scientific research, as reported in a newspaper article. Read the article and answer the questions that follow.

Study links low income with high blood pressure
1. What two variables are correlated according to the article?
2. Is this proposed as a direct or inverse correlation? Explain.
3. Does either the author or researcher argue that one of the variables causes the other? Explain
4. What other explanations could there be?