BI 171 - Fourth Exam - 2000

NOTE - the numbers link to related information in the book.  Not all information on old exams is in the new book (so some numbers have no link), and if something looks unfamiliar, you can check to see if it's from a chapter you're supposed to be studying for your current exam.

Multiple Choice.

Place the letter of the choice that best answers the question on the line to the left.
Two Points Each. NOTE: "e" answers are never the correct answer.

_______ 1. Crossing over occurs during
                           a. Fertilization             b. Cytokinesis             c. Synapsis
                           d. Replication                     e. I thought I knew this one...

_______ 3. Ferredoxin
                           a. Picks up and moves electrons during respiration
                           b. Picks up and moves electrons during photosynthesis
                           c. Is the cytoplasmic link of the typical signalling pathway
                           d. Is the membrane link of the typical signalling pathway
                           e. Is an old French song about somebody's brother's dachshund

_______ 4.  During Meiosis II,
                           a. Chromosome strands separate 
                           b. Chromosome pairs separate
                           c. 4N cells produce 2N cells 
                           d. 2N cells produce 1N cells
                           e. Lots of cool stuff happens

_______ 5. The coding part of a gene is called a(n)
                           a. Operon                 b. Regulon                 c. Intron
                           d. Exon                         e. The part that has the code

_______ 6. Which is the best explanation for why it is common for genes to be in sequences that match pathway sequences in prokaryotes?
                           a. There is no transfer RNA in prokaryotes
                           b. The genes actually perform as enzymes in the pathways
                           c. Chromosomes leave the nucleus when needed
                           d. Ribosomes are in actual contact with the genes
                           e. Because if it wasn't common you couldn't ask this question

_______ 7. The dominance of an allele is determined by
                           a. The likelihood of it being passed on 
                           b. The effect of its protein
                           c. How often it is transcribed 
                           d. How common it is in a population
                           e. Its general level of self-esteem

_______ 8. The light-dependent reaction of photosynthesis, over several steps, transfers light energy to what intermediate used in the light-independent reaction?
                           a. Chlorophyll         b. Glucose         c. Water         d. ATP
                                                   e. Short-term Treasury Bonds

_______ 9. An anticodon is found on
                           a. rRNA             b. mRNA             c. tRNA             d. DNA
                                               e. A sofa next to the uncly-codon

_______ 10.  Which microfilaments are the major components of muscle?
                           a. Dynein & kinesin                 b. Actin & myosin 
                           c. Actin & clathrin                    d. Histone & Chaperonin 
                                               e. Tuggitin and uffda

_______11. Analysis of very small samples of DNA is made possible through what procedure?
                           a. Gene enhancement                             b. Southern blotting
                           c. Activator-promoter amplification        d. Polymerase chain reaction
                                                e. The tiny tweezer technique

_______12. Prokaryotes are most likely to keep around their
                           a. Housekeeping proteins                         b. Alarmones
                           c. Polar bodies                                         d. Barr bodies
                                               e. Most comfy pair of socks

_______13. A unicellular organism moving down a concentration gradient toward a food source is an example of
                           a. Diffusive behavior         b. Transduction         c. Bulk transport
                           d. Chemotaxis                     e. What happens when it forgets to shop

_______14. Genes may be directly accessed by
                           a. Transfer RNA             b. G proteins             c. Steroid hormones
                           d. Coated pits                 e. Giving them a little tickle

_______ 15.  Intermediate filaments are commonly found in cells
                           a. Under mechanical stress                  b. While they are dividing
                           c. While they are moving                     d. While DNA is being replicated
                                       e. That just can't make up their tiny little minds

_______16. In a family, the sex-linked trait of color-blindness shows up in one son and in only one of three daughters. Which should be true?
                           a. Both parents are color-blind
                           b. Neither parent is color-blind
                           c. The father is color-blind but the mother is not.
                           d. The mother is color-blind but the father is not.
                           e. They were all adopted

_______ 17.  Experiments with Neurospora molds led to what discovery?
                           a. Genes could spontaneously mutate
                           b. DNA is the carrier of genetic information
                           c. Enzymes are coded by genes
                           d. Genes exist in various allele forms
                           e. That yucky stuff in the back of the refrigerator can kill you

_______18. The signal region on a protein helps to determine
                           a. What sort of receptor it is                   b. Where in a cell it will go
                           c. What gene will be transcribed             d. The cell's gender
                                       e. Where explorers can plant their flags

Short Answer.  

Pick NINE questions to answer in the spaces provided.
NOTE: if you answer MORE than nine, only the first nine will be corrected.

Four Points each. Partial credit is possible.

1. How is assimilation different from consumption?

3. What makes certain cell structures epigenetic?

4. Photosynthesis releases oxygen as a byproduct. From which substrate molecule does that oxygen come?

5. What are Okazaki fragments?

6. Briefly explain why deletions are more likely to be a harmful mutation than substitutions.

7. What are two specific ideas developed by Gregor Mendel?
8. As multicellular organisms grow, what two different patterns can occur on a cell level?
9. Give two different possible reasons for the evolution of metamorphosis from larval to adult form.

10. Approximately how much does it cost (in ATPs) to build a protein?

11.   Briefly explain how position effect works.

12. Give two examples (they don't have to be biological) of

Positive Feedback & Result:

Negative Feedback & Result:

13. What is alternation of generations?

14. What is a karyotype?

15. Give two examples of different types of signal ligands.

16.  How does a prokaryote make sure that each of two new daughter cells gets a chromosome?

Long Answer.  

Select and answer completely any four of the following questions.
Note: if you answer more than four, only the first four will be corrected.
Seven Points Each. Partial credit is possible.

1. Give the missing steps of the typical eukaryotic transduction pathway:

Starting_____________________________________________________________
Strand          T  A  C  T  C  G  G  T  A  A  T  G  C  C  T  A  T  C  T  C  A  A  T  T

Other DNA___________________________________________________________
Strand

Amino Acid__________________________________________________________
Sequence Use the table attached to the end of the exam.

4. Show with a drawing the following processes. Label the steps and the resulting cells.

4. Explain, step by step, the basic procedure of Southern Blotting.

5. What are four different functions of microtubules?

6. Describe three steps each (in order) for the two parts of photosynthesis:

7. For the four mitosis phases of the cell cycle (one phase is NOT part of mitosis!), give the name of the phases in order and tell one thing that happens only during that phase.

LINK TO ANSWER KEY.

BONUS QUESTIONS. Answer as many or as few as you wish. You can't lose points on the rest of the exam by getting these wrong. Partial credit is possible.

What fact suggests that actin may be close to a "perfect" molecule? Four Points.

What important research areas are very interested in telomeres (Two Points each), and what telomere functions are being addressed in these areas (Three Points each)?

How do mitochondria fit into one of the theories about the origins of genders in sexual reproduction? Four Points.

What sorts of specific needs seem to have led do development of alternation of generations? Four Points each.

What is a chromosome "puff"? Four Points.

Single-base point mutations often have no noticeable effect. For Four Points each, what are the various reasons for this?

Use this table for the DNA question in the Long Answers. Read it using the mRNA sequence for codons - line up the first letter line block with the second letter column and the third letter line to get the amino acid. Amino acids can be represented with just their first three letters except for two pairs who share the first three letters: glutamine (gln), glutamate (glt), asparagine (asn), and aspartate (ast).

It's okay to tear this sheet off the lab. Make sure you put your final answer from this in the proper place in the long answer section.

Copyright 2002, Michael McDarby.