SC 135 - Second Exam 2000
Answer Key
MULTIPLE CHOICE.
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. When a molecule too big to fit through membrane pores
moves from a high concentration
___C___ a. Active transport b. Osmosis
c. Facilitated diffusion
...the movement direction says diffusion, and
the description says
it's diffusion with help, or facilitated
2. In general, if you compare an element’s common ion
to its uncharged atom form, the ion
should be
___B___ a. More likely to be radioactive
b. Chemically more
stable
c. Less likely to be radioactive
d. Chemically less stable
e. Available in more styles and colors
...an atom becomes more chemically stable by forming
the ion,
adjusting the "fullness" of the outer electron shell.
3. Cells are often given structure with
___D___ a. Cilia
b. Nucleolus
c.
Endoplasmic reticulum
d. Microfilaments
e. Strict upbringings
...these are one of the components of cytoskeleton.
4. Which type of molecules have many different
functions because of their
limitless ability
to be different shapes?
___A___
a. Proteins
b. Nucleic Acids
c. Carbohydrates
d. Lipids
e. Silly Putty
...part of the features of proteins.
5. The reaction CO2 + H20 ----> C6H12O6 + 6 O2 represents
___B___
a. Aerobic respiration
b.
Photosynthesis
c. Enzyme activity
d.
Hydrolysis
e. More than I ever wanted to know
...production of oxygen and sugar is a big clue.
6. Which is a base bonding combination in nucleic acids?
___D___ a. Glucose - Glycerol
b. Thymine - Cytosine
c. Adenine - Guanine
d. Adenine - Uracil
e. "Base bonding" sound like we’re sticking
statues together
...it could have been Adenine - Thymine, or Cytosine -
Guanine
as well.
7. Two different isotopes of the same element have different numbers of
___C___ a. Protons
b. Electrons
c. Neutrons
d. Nuclei
e. Zip
codes
...part of the definition.
8. The pH of digestive juices in the
intestine is between 7.5 and 8.5. Compared with a
neutral pH, the concentration of
H+ ions should be
___B____ a. Higher
b. Lower
c. Equal
d. There's no way to tell
e. I guess I shouldn’t have skipped this one
in the book
...pH above 7 (neutral) is more OH- and less H+.
9. Which is an allowable species name, according to the rules?
___A___
a. Rattus rattus
b. rattus
rattus
c. Rattus Rattus
d. rattus
Rattus
e. There are rattus rules? Weird!
...first word capitalized, second one not.
10. If a cell is known to be secreting some sort of protein, then what cell
organelles__A___
a. Ribosomes & Golgi bodies
b. Ribosomes &
vacuoles
...ribosomes make the proteins, Golgi bodies prepare it and secrete it.
11. The growth of a plant or animal would have to directly involve
___D___ a. Endocytosis
b. Hydrolysis
c. Osmotic pressure
d. Dehydration synthesis
e. A doorway with little pencil marks on it
...this is the process that's used to build molecules needed for growth.
12. Which is not a use for lipids in living things?
___B___ a. Storing energy
b. Moving things
c. Hormones
d. Water barriers
e. Making students remember answers
...moving things is a use for proteins.
SHORT ANSWER.
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. A red blood cell (with a membrane permeable to water) is put into a hypertonic salt solution. What should happen to the cell?
...the solution would have more particles and less water than the cell, so the water should move from inside (higher concentration) to outside (lower concentration), so the cell should shrink.
2. Compounds with ionic bonds very rarely have any function in living systems. Why is that?
...ionic compounds almost always come apart in water.
3. Give a definition of the term allele.
...it's a variation of any particular gene.
4. Both carbon and water are essential to life. How are the bonding characteristics of each important aspects of their biological importance?
|
CARBON: With four available bonds, |
WATER: Bipolar nature allows
molecules |
5. What two features of mitochondria led to the idea that they might have originated as endosymbionts?
| Physically very similar to types of bacteria known. |
Have their own, bacterial-type DNA. |
6. What are the basic principles of the cell theory?
|
All living things are made up of at least one cell. |
|
The cell is the smallest unit that is actually alive. |
|
Cells only come from other, related cells. |
7. Name and briefly define two different types of bonds that can hold molecules together. There are more than two.
| COVALENT |
Atoms share electrons. |
|
HYDROGEN |
Attractions between partial charges. |
| IONIC | Attractions between opposite-charged atoms. |
8. If a molecule goes through oxidation, what by definition has happened to it?
...it has lost at least one electron.
9. Fill in four labels on this drawing of a cell: Labels point to organelles on a simple line drawing.
|
---------------------------------- ---------------------------------- ------------------------- ------------------------- ------------------------- -------------------------
|
10. What are two sets of differences between (other than names or initials) -
|
DNA |
RNA |
|
Double-stranded |
Single-stranded |
|
Contains Thymine |
Contains Uracil |
| Contains Deoxyribose | Contains Ribose |
11. What feature or features does a molecule need to have to be considered organic according to the newest definition?
...contains Carbon and Hydrogen.
12. Put them in order, SMALLEST TO LARGEST: Class, Family, Genus, Kingdom, Order, Phylum, Species, Superorder.
|
1 SPECIES |
2 GENUS |
3 FAMILY |
4 ORDER |
|
5 SUPERORDER |
6 CLASS |
7 PHYLUM |
8 KINGDOM |
13. What are two structures found in both eukaryotes and prokaryotes? There are more than 2.
|
CELL MEMBRANE |
CHROMOSOMES |
| CELL WALL | RIBOSOMES |
14. What are two effects that would happen inside your cells if your lysosomes stopped working?
|
White blood cells would not be able to digest particles taken in. |
Cells that should die will not be able to. |
15. Briefly explain where the two terms come from in the Fluid Mosaic Model:
|
FLUID - Phopspholipid molecules move |
MOSAIC - Other molecules, mostly |
LONG ANSWER.
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. For four different properties of water, give the term associated with that property in the first column, and give an example of that property in action in the second column.
|
TERM |
EXAMPLE |
|
COHESION |
Produces surface tension, holds liquid in vessels together, etc. |
|
ADHESION |
Water in paper towels, blood moving up a tiny sample tube, etc. |
|
HEAT STABILITY |
Bodies of water are stable and help stabilize climates, etc. |
|
EXPANSION WHEN FREEZING |
Ice forms and stays on the surface, isolating and insulating liquid layers underneath for things to live in, etc. |
| WIDE SOLVENT ABILITY | Biological chemistry depends upon many different things floating around in solution. |
2. Name three types of adaptations living things use against osmotic pressure. For each, explain how that adaptation keeps osmotic pressure from harming the organisms.
| WATERPROOFING |
Prevents inflow of water |
|
PUMPS |
Moves incoming water back out. |
|
RIGID OUTER WALLS |
Will not allow membranes to expand to the point of breaking. |
3. The atoms in this molecule are either Carbon(C), Hydrogen(H), Oxygen(O), or Nitrogen(N). Based upon the bonding information given, place the appropriate symbols in the circles.
Each atom was connected to the next by bonds - the number of bonds on each is the key here.
4. For cilia and flagella, give three sets of differences, the one feature they share:
|
CILIA |
FLAGELLA |
|
Much smaller |
Much larger |
|
Always in large numbers on a cell |
Rarely more than 12 on a cell |
|
Tend to move in coordinated fashion |
Usually not coordinated |
| Do not carry added structures | May carry added structures |
|
FEATURE THEY HAVE
Similar shapes, both are extensions of cell membranes, |
|
5. Pick an element from the Periodic Table (something on Row 2 or higher). For an uncharged atom of that element, give the...
Element Name _________ Element Symbol ________
Atomic Number _________ Most Likely Atomic Weight Round Off the Number!
Number of Protons Same
as Atomic Number
Most Likely Number of Neutrons Atomic Weight Minus Proton Number
Number of Electrons Same as Proton Number
6. Name and define the four structural levels of proteins.
| PRIMARY |
Order of amino acids in the string. |
|
SECONDARY |
Local atom arrangements on the string. |
|
TERTIARY |
Overall 3-Dimensional shape from interactions among distant parts of the string |
|
QUATERNARY |
Complexes of more than one string. |
NO KEY FOR BONUS QUESTIONS.
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.
Different types of radiation from radioactive materials can have hugely different energies and penetrating power. What is it about the types of radiation that makes them act so differently? Four Points.
The right-hand column on the test’s periodic table is labeled "0." According to our rules, what should the label be (Three Points), and why does it have a zero on it (Four Points)?
What is it about the structural molecules in leaves and grass that make them a potentially great food source (Three Points), and why are those molecules so difficult to digest? (Three Points)
How many fatty acids would a typical lipid molecule have? (Three Points)
Briefly explain, step-by-step, how an antibiotic given wrongly to someone today can lead to antibiotic resistance in a disease bacterium they’ll pick up in a year. Two Points per correct step.
What two features of bony fish are indications that the group’s early evolution occurred in fresh water? Three Points each.