SCI 135 - Second Exam Spring 2015

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.  An allele is a

________  a. A type of membrane attachment                b. Molecule used for energy storage
                c. The dissolved material in a solution            d. Variation in the code of a gene
                                e. The newest flavor of alcoholic Snapple

2.  An atom that has added or lost electrons in order to be more chemically stable:

________  a. Ion         b. Acid         c. Base        d. Isotope         e. Obsessed with appearance

3.  In order to happen at a usable rate, cell reactions have to have

_______  a. Connected DNA             b. Lipids available            c. Heat supplied
               d. Enzymes available                    e. The money up front

4.  Which chemical process is essential in the digestion of food?

________  a. Dehydration synthesis             b. Spontaneous generation            c. Hydrolysis
                d. Endosymbiosis            e. Whatever weird stuff happens in barbeque sauce

5.  Someone who is lactose intolerant would have a problem digesting a(n)

________  a. Lipid             b. Protein            c. Sugar             d. Enzyme
                            e. I have no time for people who are intolerant

6.  Carbon dating only works for items younger than 60,000 years.  Why not older?

_______  a. Nothing is older than that                                       b. All of the carbon is gone
                  c. Not enough radioactive carbon left to measure         d. There are no comparison specimens
                                        e. The dating websites have rules about ages

7.  The pH of the digestive juices within the human small intestine is between 7.5 and 8.5.
                This environment could be described as

________  a. Acidic         b. Neutral         c. Basic        d. Dehydrated         e. Icky

8.  A codon has _____ the "bits" as the coded amino acid

_______  a. Half         b. Ten times         c. Two times         d. Three times         e. Eaten all the bits, forget the bits

9.  Which is most closely related to a microscope’s ability to focus clearly?

_______ a. Resolution         b. Total magnification         c. Clarity        d. Imaging         e. How drunk it is

10.  Carbohydrates include

________  a. Fats & oils                 b. Sugars & starches                c. DNA & RNA
                d. Acids & Bases                    e. One other thing I've forgotten from studying

11.  Actin and myosin are types of

_______  a. Respiratory enzymes             b. Membrane lipids            c. Digestible starches
                d. Muscle proteins                            e. Words, just words without meaning

12. Electrons are shared between atoms in

________  a. Covalent bonds         b. Ionic bonds        c. Isotopic bonds         d. Enzyme bonds
                                                e. Very picky divorce settlements


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.  For what two different, major reasons do plants produce glucose?

2.  What are the molecular "pieces" that go into a lipid?


3.  Given here is one side (strand) of DNA. Starting with this strand, show:

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

                                      Messenger RNA from 1st strand

4.  What makes a molecule organic?

5.  Many radicals are dangerously reactive. Why?

6a.  In the laboratory, what is sectioning?

6b. Why is that sectioning done?
7.  Name two different types of biological polymers.

8.  Explain what a DNA parasite is.

9.  What happens to an atom or molecule if it goes through an oxidation reaction?

10.  If more Hydrogen ions are added to a solution, what happens to the solution's pH reading?

11.  RNA and DNA molecules are built differently. Give two differences in the way the molecules are put together.

12.  What are the functions of the two molecule ends in an antibody molecule?

13.  What is it about a molecule that makes it polar?

14. Label the following chemical reaction with the general terms for each part –
        A           +             B                      x          >            C

   __________            ___________        ______________           _____________
15. What is a hydration shell?


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,  What are three different biological uses for lipids?

2.   All for the most common isotope –

How many protons?


# 4

Column 2


How many

electrons? (Radical form)

How many



ion form?

3.  Using the numbers of bonds as a guide, fill in the symbols for either Carbon, Hydrogen, Nitrogen, or Oxygen.
      Can't quite reproduce the picture - fill in your own bonds for the proper elements.
                     O                O                   O
      O            O                O                   O
      O                               O                               O
      O                                                                  O

4.  For three basic properties of water -
PROPERTY What’s happening on the molecular level




5.  Name and give a brief description for the four levels of protein structure.





6.  What are four different types of proteins involved in signaling?



7.  Give the terms for each of the two groups in each microscope category -



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.

What are people talking about if the subject is the half-life of a vitamin? Three Points.

The first version of the periodic table was organized according to what features of the elements? Three Points Each.

Earth's atmosphere is almost 75% Nitrogen. What is it about Nitrogen that has caused it to build up until it's such a large part of the air? Three Points.

Local lakes "turn over" in the fall and spring. What exactly causes this? Five Points.

Antioxidants may do a couple of not-so-helpful things in humans. What are they? Three Points Each.

What does stomach acid do to aid digestion? Three Points.

Where exactly do the numbers of the pH system come from? Three Points.

Plastics are what kind of molecules? Three Points.

Why did they decide to call it junk DNA? Three Points.

Human skin color evolves as a response to one good thing sunlight does and one bad thing. For Three Points Each, what are those things?

Why does an electron microscope have to have a vacuum inside? Three Points.



SCI 135 

Michael McDarby