Biology assignments
Ibrahim
Chapter 1 Exploring Life This chapter is designed to give you an overview of the themes of the course. For our purposes, concentrate on the section/pages indicated below and just skim the remaining pages. 1.1 Exploring Life on its Many Levels READ: Overview, Section 1.1 ( “Emergent Properties”, “The Power and Limitations of Reductionism”, “Systems Biology”, “Systems Biology at the Levels of Cells and Molecules” and Figure 1.4 skim all other subsections) |
|||
1. |
List and Briefly describe the 7 properties and processes we associate with life. Order (ex: flower structure), evolutionary adaptation (ex: seahorse camaflouged in coral reef) , respond to environment (ex: venus fly trap closes on dragonfly), regulate internal environment (ex: temperature regulation), process energy (take in food( change it into a form body can use( excrete waste), reproduce and grow and develop. |
|
|
2. |
p. 4-8 1. List the 10 levels of biological organization. Write a brief definition of each level and list an example. Level Description Example Biosphere All environments on earth that support life Earth ecosystem all the interactions among organisms living in a certain area their interaction the nonliving environmental components EX: Florida coast- Pelicans, seagulls, fish, crabs, sand, water, air… community All the interactions among the living organisms in an ecosystem Pelicans, seagulls, fish, crabs, population localized group of individuals of a species Pelicans organism An individual living entity One pelican Organ system Group of organs that work together to accomplish body functions that sustain life Cardiovascular system organ Group of several types of tissues that perform a specific function or group of functions within an organism. heart tissue a group of cells of the same type that perform a similar function Muscle tissue Cell basic organizational unit of all living organisms Cardiac muscle cell organelle a specialized subunit within a cell that has a specific function mitochondrion molecule Group of at least two atoms in a definite arrangement held together by very strong (covalent) chemical bonds. Mitochondrial protein
|
|
|
3. |
Explain how the properties of life emerge from complex organization. (Give an example of an emergent property observed in living organisms). |
|
|
. |
Many tissues make an organ. Separate each tissue that makes that organ and that organ no longer can perform its function. (ex: brain separated into tissues = brain can no longer process information) The functioning of the organ is an emergent property of that organ, based on the organization of its tissues. “The whole is greater than the sum of its parts” |
|
|
|
4. What is reductionism? Describe the dilemma of reductionism. Reductionism: Reduces complex systems to simpler components. Only one components of the system is studied. Dilemma: unable to explain all the interactions of the components of a system when only one component is studied. Lose/unable to study the emergent properties of the system. |
|
|
5. |
What is systems biology? What might one consider when looking at a flat tire on a car from a systems approach? Model the dynamic behavior of whole biological systems. Biologists will be able to predict how change in one component of the system will impact other components and the system as a whole. Biologists are able to study emergent properties of a system. When looking at a flat tire from a systems approach, you would consider the affect that flat tire has on the system as a whole (i.e. if the tire is flat you cannot drive the car). |
|
|
|
|
||
|
1.3 The Process of Science READ: p. 18-24, Skip the snake experiment! |
||
6. |
Distinguish between discovery science and hypothesis-based science. Explain why both types of exploration contribute to our understanding of nature. Discovery science: Describes natural structures and processes through careful observation and data collection. Hypothesis-based science: This type of science seeks to answer questions that are asked after observation of a natural structure or process.
|
|
|
7. |
Distinguish between quantitative and qualitative data. Quantitative: Numerical measurements. Ex. How many times an infant chimpanzee is nursed each day. Qualitative: Descriptive recording rather than numerical measurements. Ex: A description of how a mother chimpanzee reacts when her infant is attacked.
|
|
|
8. |
Distinguish between inductive and deductive reasoning. |
|
|
9. |
Inductive reasoning (used in Discovery Science): Make several specific observations over a long period of time and come to a generalization. Ex: SPECIFIC OBSERVATIONS= Every year for the past 15 years I have observed that the leaves fall off the trees in the fall. GENERALIZATION= Leaves fall off trees in the fall. Deductive reasoning (used in Hypothesis-Based Science): From a generalization you come to a specific conclusion. Ex: GENERALIZATION= Leaves fall off trees in the fall. SPECIFIC CONCLUSION (after testing)= leaves fall off the trees in the fall because the days get shorter. Explain why hypotheses must be testable and falsifiable but are not provable. Testable: There must be some way to check the validity of the hypothesis (idea/answer to the question being asked) Falsifiable: There must be some observation or experiment that could reveal if such an idea is actually not true. Not provable: No amount of experimental testing can absolutely prove a hypothesis is true…because it is impossible to test all alternative hypotheses (including the ones no one has thought of).
|
|
|
10. |
Describe what is meant by a controlled experiment. An experimental group is compared with a control group. The experimental and control groups only differ in the one factor that the experiment is trying to test. |
|
|
11. 12. |
Describe the clinical experiment discussed in class involving a cholesterol drug trial. Step1: Observation- Drug active ingredients may lower cholesterol Step 2: Question- Can this drug lower cholesterol? Step 3: Hypothesis- This drug will lower blood cholesterol Step 4: Prediction- If the cholesterol of the patients that take this drug decreased then this drug is effective at decreasing cholesterol in humans Step 5: Experiment- Experimental vs. Control group: · 2000 people with high cholesterol recruited for study · Experimental- 1000 people receive drug · Control- 1000 people do not receive drug, get placebo · Study Results: · Experimental- 93% show significant decrease in cholesterol · Control- 20% show significant decrease in cholesterol Step 6: If a hypothesis is supported by test, then we can accept the hypothesis Distinguish between the everyday meaning of the term ‘theory’ and its meaning to scientists. Everyday meaning: explanation of a an observation/problem with little experimental data to back it up; extensive testing of a hypothesis is not done Scientific meaning: explanation of an observation/problem with a great deal of experimental data to back it up; results from extensive testing of a hypothesis.
|
|
|
13. |
Explain how science is influenced by social and cultural factors. What we are able to understand in the world around us is influenced by current social and cultural factors. For example, changing attitudes about recruiting women for human research studies has increased the number of women who participate in these studies . Several decades ago, a majority of the people recruited for human research studies were men. As a result, certain diseases such as heart disease were thought to occur in men more often than in women. Over the last several years more and more women have been recruited for such studies and it has been uncovered the risk women face for developing heart disease is equal to that of men. |
|
|
14. |
Identify and describe the 6 steps of the Scientific Method. Provide an example similar to the flashlight example discussed in the chapter and the powerpoint Please refer to the powerpoint slides detailing the flashlight example |
|
|
|
|
Suggested End of Chapter SELF-QUIZ questions:
#1, 2, 4, 7-10
SEE answers in the back of the textbook!