SCI 135 - Third Exam Fall 2016
Links connect to relevant parts of the online book.



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

        1.  During fertilization,

_______    a. Diploid cells get together                          b. Haploid cells get together
                c. One diploid cell joins one haploid cell        d. All of these can happen
                                        e. Fertility is, umm, made fertilaceous...

        2.  If cells are going to pick up extra gene copies, it’s probably going to happen during

_______    a. Interphase         b. Meiosis I         c. Meiosis II        d. Mitosis         e. Happy Hour

        3.  Spindle fibers are made of

__________    a. Microfilaments         b. Cilia         c. Microtubules        d. DNA         e. Spindly stuff

        4.  Cancer is most likely to happen in cells that are normally

_______    a. Dormant         b. Dividing        c. Involved in antibody production         d. Dead
                                    e. Spending most of their days on Facebook anyway

        5.  What are HIV escape mutants escaping?

_______    a. The body, spreading to others            b. The cells, where many have been trapped
                 c. Antibody attachment                         d. All of these
                                    e. A plot of a bad movie

        6.  In a double-stranded chromosome, a telomere can be found

_______    a. Holding each strand together            b. Side-by-side - it is the name of the strands
                 c. Only during telophase                      d. At the end of each strand
                                        e. Only if you really really want to find it

        7.  A point mutation occurs at what “point”?

_______    a. DNA nucleotide         b. Centromere        c. Chromatid         d. Anaphase
                                                            e. A mutation point

        8.  Histones are used for

__________    a. Lowering activation energy             b. Winding up DNA            c. Grabbing chromosomes
                      d. Capturing some light energy                    e. Weren't they an old 50's singing group?

        9.  HOX genes are going to be active mostly in

_______    a. Respiratory systems         b. Proofreading systems        c. Early embryos         d. Prokaryotes
                                                                    e. Hairball production

        10. In dividing cells, actual cell division occurs

_______    a. Only in telophase            b. In anaphase or telophase            c. In telophase or interphase
                d. In interphase, telophase, or anaphase            e. When cell parts get really angry with each other

  11.  What produces the “rough” part of rough endoplasmic reticulum?

_______    a. Nucleoli         b. Ribosomes         c. Microfilaments        d. Vesicles         e. The neighborhood

        12. Which has a codon on one end and an attachment for an amino acid on the other?

__________    a. Transfer RNA             b. DNA             c. Enzyme             d. Messenger RNA
                                            e. Sounds like sitting down would be a problem

Answer any eight of the following questions for 4 Points Each.

Note: if you answer more than eight, only the first eight will be corrected.
You can get partial credit on these answers.

1.  What two different materials are combined in chromatin?


2.  What are two different general functions that are performed during interphase?


3.  What is meant by genetic linkage?

4.  Briefly describe the two different types of genetic redundancy.


5.  What is apoptosis?

6.  Give each one’s advantage, compared to the other one -

7a. What sort of organelle would be more numerous in cells found in a gland?

7b. Why would those organelles be more numerous there?

8.  Cells infected with prions often stop working properly. How do the prions make the cells stop working?

9.  For some mutations, a position effect is created. How does that effect work?

10. Why are Barr bodies formed?

11. Why is it called a nuclear envelope instead of a nuclear membrane?

12. What two molecular-complex organelles are involved in some sort of RNA processing?


13. What, technically, is a gene?

14. Why is a deletion mutation much more dangerous than a substitution mutation?

15. What are two different, specific effects that make multiple DNA breaks, such as can happen from radiation, dangerous?


16. Polyploidy mutations can be found in what sort of living things?


Answer any four of the following questions for Eight Points Each.
Note: if you answer more than four, only the first four will be corrected.
You can get partial credit on these answers.

1.  Give three sets of differences (other than the associated genders) between -




2.  Using this DNA code give the messenger RNA sequence and, using the chart attached to the back of the exam, give the coded amino acid sequence.
Strand     T  A  C  A  A  C  G  A  A  C  A  G  G  G  G  C  C  C  T  A  G  A  C  G  A  T  C

mRNA _________________________________________________________________________________________


3.  What are three sets of differences between mitosis and meiosis?




4a. Briefly explain the endosymbiont theory.

4b. What two structures are associated with the endosymbiont theory?


5. For each of the three cell layers found in most animals, give the name of the layer and one system that develops mostly from that layer.




6.  For four different types of vesicles or vacuoles, give the name and function:





7.  For the four phases of mitosis (so not the one between), name the phases in order and give one specific thing for each that happens particularly in that phase.





Link to Answer Key


Answer as many as you are able. Wrong answers will not result in points being lost from the main exam. You can get partial credit on these answers.

People usually pronounce “apoptosis” wrong – what’s the common mistake? Three Points.

What common feature, not part of the basic definition, makes most recessive alleles recessive? Three Points.

A new company called Teloyears are selling their tests on tv and online. Based on their name, what are they running tests on and what condition are they addressing? Three Points.

What group of animals have matched chromosomes in males and unmatched chromosomes in females? Three Points.

In a double-stranded chromosome, what part is new and what part is old? Three Points.

When cells turn into cancer, they spend less and less time in interphase. Why? Three Points.

In humans, even though only one egg cell at a time should be ovulated, 4 to 7 actually begin to develop in the ovaries. Why the extras? Three Points.

In humans, when a sperm nucleus enters an egg cell, it can’t immediately join with the egg cell nucleus. Why not? Three Points.



SCI 135 

Michael McDarby