General Biology I
Biology 1406
LOCKLIN
Name_______________________________
June 17, 2004
Exam II-A
I. (30 points) Multiple choice. Select the correct answer for each question and place the answer on your
exam in the blank to the left of the number.
____1.
a.
b.
c.
d.
e.
How are plasma membranes best described?
A double layer of phospholipid molecules with hydrophobic tails directed toward cytoplasm of the cell.
A single layer of phospholipid molecules with water molecules attached along one side.
A double layer of phospholipid molecules with hydrophilic heads directed toward each other.
A double layer of phospholipid molecules with hydrophobic tails oriented toward each other.
A single layer of phospholipids with tails pointed to the inside of the cell.
____2.
a.
b.
c.
d.
e.
Within the fluid mosaic of a plasma membrane, what is the role of transport and channel proteins?
They prevent passage of amino acids.
They allow movement of salts and sugars through the plasma membrane.
They may set off cellular changes such as cell division or hormone secretion.
They are cell-surface attachment sites.
They identify the cell.
____3. The net movement of molecules from a high concentration to a low concentration is described by which of the
following?
a. diffusion
b. active transport
c. Osmosis
d. facilitated diffusion
e. exocytosis
____4.
a.
b.
c.
d.
e.
If red blood cells are taken from the body and placed in a hypertonic solution, what happens to the cells?
The cells swell and burst because water moves into the cells.
The cells shrivel up because water leaves the cells.
The cells remain unchanged due to equal solute concentration inside and outside the cells.
The cells remain unchanged due to equal water concentrations inside and outside the cells.
They become white blood cells.
____5.
a.
b.
c.
d.
e.
A freshwater protozoan, such as Paramecium, tends to _______ because it lives in a _______ environment.
gain water; hypotonic
lose water; hypertonic
gain water; hypertonic
lose water; hypotonic
gain water; isotonic
____6. Osmosis moves water from a region of
a. high concentration of dissolved material to a region of low concentration.
b. low concentration of dissolved material to a region of high concentration.
c. hypertonic solution to a region of hypotonic solution.
d. negative osmotic potential to a region of positive osmotic potential.
e. low concentration of water to a region of high concentration of water.
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____7.
a.
b.
c.
d.
e.
The urinary bladder is protected from leaking due to cell-to-cell junctions called:
Desmosomes
Tight junctions
Gap junctions
Plasmodesmata
Stretch receptors
____8.
a.
b.
c.
d.
e.
All cells possess all the following components except:
Cytoplasm
Genetic material
Nuclear membrane
Plasma cell membrane
Ribosomes
____9. What is the difference between "free" and "attached" ribosomes?
a. Free ribosomes are in the cytoplasm while attached ribosomes are anchored to the endoplasmic reticulum.
b. Free ribosomes produce proteins that remain in the cytosol while attached ribosomes produce proteins that may
be exported from the cell.
c. Free ribosomes produce proteins that are exported from the cell while attached ribosomes make proteins for
mitochondria and chloroplasts.
d. a and c.
e. a and b.
____10. What is the function of a central vacuole?
a. Storage of wastes
b. Support of the cell
c. Excretion of wastes
d. a and b
e. b and c
____11. The golgi packages materials into _________ for transport or export.
a. organelles
b. plastids
c. vesicles
d. microns
e. nucleoli
____12. Which cellular component packages hydrolytic enzymes and forms lysosomes?
a. Golgi complex
b. Smooth ER
c. Mitochondrion
d. Cytoskeleton
e. Rough ER
____13. An organelle associated with carbohydrate synthesis is the:
a. Golgi complex
b. Ribosome
c. Centriole
d. Nucleolus
e. Nucleus
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____14. What primarily determines the shape of cells that lack cell walls?
a. Nucleus
b. Cytoplasm
c. Endoplasmic reticulum
d. Cytoskeleton
e. Ribosomes
____15. Which of the following is capable of converting light energy to chemical energy?
a. Chloroplasts
b. Mitochondria
c. Amyloplasts
d. Vacuoles
e. Golgi bodies
____16. Which of the following has the greatest amount of kinetic energy?
a. Tank of gasoline
b. Moving car
c. Hot car engine
d. Cool air surrounding the engine
e. An unlit firecracker
____17. Which of the following is part of the first law of thermodynamics?
a. Energy cannot be created or destroyed.
b. Kinetic energy is stored energy.
c. Energy cannot be transferred or transformed.
d. Exergonic reactions are coupled with endergonic reactions.
e. Potential energy equals kinetic energy in a reaction.
____18. In exergonic chemical reactions:
a. Reactants have more energy than products.
b. Reactants have less energy then products.
c. Reactants and products possess equal amounts of energy.
d. Energy is stored by the reactions.
e. Catalysts are required.
____19. The most common energy carrier molecule of living organisms is:
a. ATP
b. Inorganic phosphate
c. DNA
d. Glucose
e. NADPH
____20. A "high-energy" bond of an ATP molecule is located between:
a. Adenine and ribose
b. Two phosphate groups
c. Ribose and first phosphate group
d. Adenine and first phosphate group
e. Both b and c
____21. ATP is an energy carrier. Where is the energy actually located?
a. attached to the phosphate group
b. in the bonds between phosphate groups
c. attached to the nucleotide
d. inside the phosphate
e. between the sugar and the phosphate
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____22. Coenzymes function by ...
a. bonding to the enzyme and weakening the bonds of the substrate.
b. binding to the substrate and weakening the bonds of the enzyme.
c. binding two or more substrates and joining them.
d. helping substrates find enzymes.
e. joining together to form an enzyme.
____23. Endproducts of biosynthetic pathways often act to block the initial step in that pathway. This phenomenon is
called
a. negative inhibition.
b. denaturation.
c. irreversible inhibition.
d. feedback inhibition.
e. endproduct inhibition.
____24. What structural feature of a leaf allows a leaf to obtain CO2 from the air?
a. Stomata
b. Epidermis
c. Cuticle
d. Mesophyll
e. Chloroplast
____25. The vast majority of chloroplasts found in a leaf are located where?
a. Vascular bundles
b. Cuticle
c. Epidermis
d. Stroma
e. Mesophyll
____26. The replacement electrons for the reaction center of photosystem II come from:
a. Photosystem I
b. H2O
c. Glucose
d. O2
e. NADPH
____27. Energy is passed around different chlorophyll molecules until it reaches a specific chlorophyll molecule called
the:
a. Reaction center
b. Photoelectric point
c. Electron carrier molecule
d. Accessory pigment
e. Nucleus
____28. Light-dependent photosynthetic reactions produce:
a. ATP, NADPH, O2
b. ATP, NADPH, CO2
c. Glucose, ATP, O2
d. Glucose, ATP, CO2
e. ATP, NADPH, H2O
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____29. Where is glucose synthesized?
a. Thylakoids
b. Cytoplasm
c. Matrix
d. Stroma
e. Intermembrane compartment
___30. Cells are generally small in size based on their __________________ ratio of ____________.
a. surface area: volume; 1:3
b. surface area: volume; 3:1
c. volume: surface area; 10:1
d. volume: surface area; 1:10
e. a & c only
II. (15 points) Fill in the blanks with the correct word or statement. The value of each question is in the
parentheses following the number.
1. (1) mRNA carries information for protein synthesis from the DNA in the nucleus to the ribosomes in the cytoplasm.
To get from the nucleus to the cytoplasm, mRNA must pass through a ___________________________.
2. (1) Name one way in which plant cells differ from animal cells.
________________________________________________________________________________________.
3. (1) ________________________ is the diffusion of water molecules across a differentially (semi-) permeable
membrane.
4. (1) In chemical reactions, the ____________________ is converted into products.
5. (1) Energy "waiting to happen" is known as __________________ energy.
6. (1) Substances may move across a cell membrane very easily if they are (name one characteristic)
________________________________________________.
7. (3) The three types of endocytosis are ______________________________, _________________________ and
____________________________.
8. (1) The combination of oxygen with RuBP during the light-independent reactions, rather than carbon dioxide, is called
___________________________.
9. (1) __________________ are biological catalyst.
10. (1) If an animal cell is placed in a solution which is hypotonic to it, it will probably eventually
____________________________________________.
11. (1) Facilitated diffusion and active transport both require ______________ for the movement of molecules across the
membrane.
12. (2) Although both extensions from the cytoplasm serve to move the cell or move fluid past the cell, the
___________________ are often short and numerous, while the _____________________ are longer and few in number.
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III. (15 points) Labeling.
A. (8) Use the names, processes, etc., at the bottom of the page to fill in the blanks in the following diagram.
(6) _______________________
(1) _________________________
(7) __________
2 e(3)_____________
2 eNADP=
(4) _________________
(5) _______________________
(2) _____________________
2 H20  2
H+
+2
e-
(8) ___________________________________
(name of this part of the process)
+ H2O + ½ O2
Photosystem I
Reaction Center Molecule (P720)
Photosytem II
Electron Acceptor
NADP
ATP
ADP + Pi
Reaction Center Molecule (P680)
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B. (7 points) Below is an illustration of a membrane. Label all the parts indicated.
1. _____________________
2. _____________________
3._____________________
4. ________________
5. _________________
7. ____________________
6. __________________
Adenosine Triphosphate
Phospholipid bilayer
Recognition protein
Extracellular fluid
Cholesterol
Transport Protein
Binding site
Mitochondria
Golgi complex
Carbohydrate
Microfilaments (protein filaments)
Cytoplasm
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IV. Lab Material (15 Points)
1. (1.5 points) What are the three layers in the leaf?
2. (1 point) What is the function of the cuticle?
3. (4 points) You put a plant cell in a solution of 7% NaCl. Draw what the cell would look like after 5
minutes. Label the cell wall, the cell membrane, chloroplasts, and the nucleus.
4. (1 point) The enzyme found in saliva that breaks starch down to maltose is called __________________.
5. (1 point) What was the role of the acid in the test tubes in the enzyme experiment?
6. (1.5 points) Graph the actual data below that was generated in the enzyme lab. Was this data taken from the ice
bath or the warm bath?
Time (minutes)
0
3
6
9
12
Transmittance: 25%
26%
45%
55%
60%
Label the following. Each is worth 1 point.
95% H2O
(3) __________ % H2O
15% solute
(1) __________% H2O
In comparison to the cell, the solution is a(n)
(2) ____________________ solution.
4._________% H2O
5. _________% solute
The solution is isotonic to the cell. Make the
figure fit the situation. (NOTE: the cell
cannot be 100% H2O)
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V. (20 points) Matching. Place the letter of the correct answer from Column B into the blank to the left of
the term in Column A. NOTE: There are more answers in Column B than you will need.
A
____1. cytoplasm
____2. active transport
____3. phosphorylation
____4. passive transport
____5. ribosome
____6. active site
____7. prokaryotic cell
____8. endergonic reaction
____9. carotenoids
___10. granum
___11. heterotrophs
___12. "9+2" arrangement
___13. microtubules
___14. C4 cycle
___15. enzyme inhibitor
___16. mitochondrion
___17. diffusion
___18. Turgor
B
a. the movement of a substance from a spot of high concentration to one
of lower concentration
b. some substance (molecule, ion, etc.) which attaches to a secondary
site of an enzyme to "switch it off"
c. a stack of membranes inside a chloroplast
e. any reaction which absorbs energy
f. pressure developed within a cell (usually in the central vacuole) as a
result of osmotic water entry
g. a polar compound; dissolvable in water
h. an accessory pigment involved in the absorption of light for
photosynthesis
i. the "powerhouse" of the cell
j. CO2 is eventually turned into C6H12O6
k. the simplest of all living cells; contains no organized nucleus
l. the largest of the cytoskeleton elements; helps "direct traffic" inside a
cell
m. no energy transformation is ever entirely efficient
n. cellular membranes studded with ribosomes; site of protein synthesis
o. the arrangement of filaments inside a cilium or flagellum
p. the place on an enzyme surface where a substrate molecule can fit
q. have to have food already made; cannot make their own food
r. starch and glycogen are good examples
s. an "extra" cycle typical of grasses of hot, dry regions of the world
which makes them much more efficient photosynthesizers than
expected
t. having a true nucleus and many internal organelles
u. movement of materials across the cell membrane due entirely to the
"force" of diffusion
v. the water-based material interior to the plasmalemma (cell
membrane) and outside the nucleus
w. the movement of materials across a membrane in which ATP is used
x. placing of a phosphate group onto a molecule
y. organizing centers for nuclear division in animal cells; always found
near the nucleus
z. consist of a small and large subunit; can be free-floating or attached to
the endoplasmic reticulum
___19. Second Law of
Thermodynamics
___20. rough E. R. (endoplasmic
reticulum)
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ESSAY (10points) Choose ONE of the following essays. DIAGRAMMATIC ILLUSTRATIONS ARE
ESSENTIAL IN YOUR EXPLANATIONS!
A. (10 points) Describe active transport in general terms and then discuss how the Na+ - K+ ion pump works. You need to
address the following points:
1. (4 points) Define active transport and explain why cells must use such transport mechanisms.
2. (2 points) Where in the cell is the Na+ - K+ ion pump located?
3. (4 points) Explain the steps of the pump one after the other IN ORDER.
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B. (10 points) Describe the cellular pathway beginning with the DNA in the nucleus and ending with the secretion of the
protein from the cell. Be specific and thorough.
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