SC 135 - Third Exam 1999

On the line to the left, place the letter of the choice that best answers the question.
NOTE: "e" answers are never the correct answer. Six Points Each.

1. Setting up an effect to control a reaction is known as

__________    a. Activation             b. Optimization             c. Feedback 
                        d. Cofactoring                     e. Taking the easy way out

2. Spindle fibers are a type of

__________    a. Microtubules                 b. Chromosomes                 c. Membrane 
                             d. RNA                                                 e. New candy

3. A karyotype is

__________    a. Way of doing photosynthesis         b. Overall chromosome analysis  
                        c. Feature of light energy                    d. Anaphase structure 
                                    e. What airline people call the bags you stuff under your seat

4. Occam’s razor  

__________    a. Appears during anaphase  
                        b. Explains how light frequency and wavelength relate  
                        c. Is part of the Krebs Cycle  
                        d. Advises that the simplest explanation is usually right  
                              e. Could be found in Occam’s medicine cabinet

5. The various roles or "jobs" performed by living things in the environment:

__________    a. Ecoroles                 b. Niches              c. Homologies             d. Fixations  
                                            e. Don’t know, but the want ads must be weird!

6. Which would have been energy sources for the development of the first  "living" molecules?

__________    a. Oxygen & Primordial Soup                 b. Sun & volcanic vents  
                        c. Water & organic molecules                 d. ATP or glucose  
                                            e. What, Niagara Mohawk wasn’t around -?

7. Oxygen debt involves

__________   a. A buildup of lactic acid in muscle cells
                            b. Removal of light during photosynthesis
                            c. Early aspects of the Heterotroph Hypothesis
                            d. Optimal respiratory enzyme levels
                            e. Another of those weird investment companies

8. A dark surface absorbing light and giving off heat is an example of

__________    a. Conversion                              b. Potential energy  
                        c. Electron transport                    d. Reradiation  
                                    e. The existence of slackers in nature

9. Meiosis produces

__________    a. 4 diploid cells                 b. 2 diploid cells                 c. 4 haploid cells  
                        d. 2 haploid cells                             e. Your what does what -?

10. The animals that survived the Cretaceous Extinction that killed most of the dinosaurs 
                                were most likely

__________    a. Small scavengers                         b. Small plant-eaters  
                             c. Sea animals                                 d. Single-celled  
                                            e. Out of town at the time

11. Bioaccumulation occurs with

__________    a. Chlorophyll and sunlight                     b. The light independent reaction  
                             c. Nutrients and pollutants                      d. Anaerobic respiration  
                                        e. Some of the stranger mutual funds

SHORT ANSWER. 

Answer any ten of the following questions for 7 Points Each.
Note: if you answer more than ten, only the first ten will be corrected.

1. Define mutation.

2. Briefly explain what a coupled reaction is.

3. When, where, and why are polar bodies made?

4. In double-stranded chromosomes, the strands are called ____________________, and are connected by a structure called a _____________________________.

5. Of autotrophs and heterotrophs, which...

        ... have the greatest number of species? ___________________

        ... makes up most of the Earth’s biomass? ___________________

6. Chromosome are only visible as actual features during cell division. Why are they in a visible form at that time? What purpose is served?

7. What are the four levels of a simple food chain?

8. What are two things that happen to the high frequency radiation from the Sun when it reaches the Earth?

9. What is activation energy?

10. What are histones?

11. What are two different ways that anaerobic organisms have an impact on humans?

12. What are the two types of dietary nutrients that act as cofactors in enzyme reactions?

13. Define alternation of generations.

14. What are two different ways that organisms can determine gender in species that have genders? (A way would explain how both sexes appear.)

15. What are the three jobs performed by codons?

16. The lesser photosynthetic pigments, ________________ reflect mostly______________

and absorb mostly ____________________________________________________________.

17. When only 2% of the energy in the light that hits chlorophyll winds up in chemical bonds, what, according to the laws of thermodynamics, happened? Both laws are at work here.

18. In chemical evolution, what are two ways that a molecule can compete with another molecule?

Answer any four of the following questions for 16 Points Each.
Note: if you answer more than four, only the first four will be corrected.

1. For the steps in aerobic respiration:

2. For the main photosynthesis reactions:

3. What two important but very different jobs are done by cells in interphase?

4. Step-by-step, describe how meiosis differs from mitosis. You only have to deal with the steps that meiosis does differently.

5. Fill in the blanks about the process of protein production.

        _________________(what?) is made from one side of DNA in the ______________(where?);

       it moves out to ______________(where?), at which point ________________ molecules bring

      in the ______________ molecules which will bind together to form a protein.

6. What are four different ways that, under normal conditions in nature, an enzyme can be "turned off."

7. For the four phases of mitosis (remember, one of the phases is not part of division!), name the phases in order and for each one, describe one thing that occurs only during that phase.

Answer as many as you are able. Wrong answers will not result in points being lost from the main exam.

What two areas of human health may be greatly affected by research on telomeres? Four Points each.

Explain why radiation affects cancer cells much more than most regular body cells - what exactly is happening to kill the cancer but leave the other cells relatively unaffected? Ten Points.

What is the main advantage (Six Points) and the main disadvantage (Six Points) to being warm-blooded?

The first theories on the origin of Life on Earth had to come up with a way for autotrophs to "spontaneously" arise. Why was that thought necessary? Four Points.

What two-step process (combining of two separate processes) might have led to the evolution of photosynthesis? Six Points.

What process (give the steps) leads to the turning of the leaves in the fall? Six Points.

It is thought that Adirondack lakes are "dying off" due to acid rain. What other explanation could be likely? Six Points.