QUESTIONS WITH COMPLETE
ANSWERS
What is the advantage of cells being so small?
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a. Small cells contain a greater quantity of enzymes than large cells.
b. Small cells do not require energy and get everything they need from osmosis.
c. The cell has a smaller surface area to volume ratio which means it can move
nutrients into the cell and waste out more efficiently.
d. The cell then has a larger surface area to volume ratio which means it can move
nutrients into the cell and waste out more efficiently. - ANSWER-c. The cell has a
smaller surface area to volume ratio which means it can move nutrients into the cell
and waste out more efficiently.
The rough endoplasmic reticulum is a cell structure that consists of folded
membranes that contain ribosomes. What is the advantage of the folded
membranes?
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a. Increases surface area in order to produce more proteins.
b. Decreases surface area in order to produce more proteins.
c. Increases volume of the endoplasmic reticulum in order to produce more energy.
d. Decreases volume of the endoplasmic reticulum in order to make more energy. -
ANSWER-a. Increases surface area in order to produce more proteins.
If a cell's lysosomes were damaged, which of the following would most likely occur?
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a. The cell would produce more proteins than it needs.
b. The cell would have chloroplasts that appear yellow rather than green.
c. The cell would be less able to break down molecules in its cytoplasm.
d. The cell would be less able to regulate the amount of fluid in its cytoplasm. -
ANSWER-c. The cell would be less able to break down molecules in its cytoplasm.
When Streptococcus pneumonia are exposed to an antibiotic, the bacteria try to
pump the antibiotic out of their cells. Which of the following mechanisms is most
likely used by the Streptococcus pneumonia to pump the antibiotic out of their cells?
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a. Active transport
b. Diffusion
c. Facilitated diffusion
d. Osmosis - ANSWER-a. Active transport
In pure water, a red blood cell from an animal will swell and burst, but a leaf cell from
a plant will not. Which structure in the leaf cell is responsible for this difference?
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a. Cell membrane
b. Cell wall
,c. Mitochondrion
d. Nucleus - ANSWER-b. Cell wall
Which of the following functions does active transport perform in a cell?
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a. Packaging proteins for export from the cell.
b. Distributing enzymes throughout the cytoplasm.
c. Moving substances against a concentration gradient.
d. Equalizing the concentration of water inside and outside the cell. - ANSWER-c.
Moving substances against a concentration gradient.
Carrot sticks that are left in a dish of freshwater for several hours become stiff and
hard. Similar sticks left in a saltwater solution become limp and soft. From this we
can deduce that the freshwater is ___________ and the saltwater is ____________
to the cells of the carrot sticks.
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a. hypotonic, hypertonic
b. hypotonic, hypotonic
c. hypertonic, hypertonic
d. hypertonic, hypotonic - ANSWER-a. hypotonic, hypertonic
In an emergency trauma room, a doctor accidentally gives a patient a large
transfusion of distilled water directly into one of his veins instead of blood. Predict
what might happen if distilled water was given to the patient instead of blood.
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a. Have no unfavorable effect as long as the water was sterile
b. Have serious, perhaps fatal effects because there would be too much fluid for the
heart to pump.
c. Have serious, perhaps fatal effects because the red blood cells would tend to
shrivel.
d. Have serious, perhaps fatal effects because the red blood cells would tend to
burst. - ANSWER-d. Have serious, perhaps fatal effects because the red blood cells
would tend to burst.
A beaker is divided into two halves, A & B, by a membrane that is freely permeable
to the water and NaCl but not to protein. Side A is half-filled with a solution of 8%
protein, while side B is half filled with a 2% protein solution. Predict what would
happen to side A after a few hours.
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a. The number of protein molecules has increased.
b. The number of water molecules has decreased.
c. The number of water molecules has increased.
d. The percentage of water has decreased. - ANSWER-c. The number of water
molecules has increased.
A research group has discovered that damselflies, a type of dragonfly, are being
infected by a particular type of aquatic protozoan. Both young and adult damselflies
are not directly infected by the protozoan but contract the infection from the prey they
eat. The graph shows the percentage of adult damselflies infected by protozoans
during the summer and early fall.
, Based on this experiment, which of the following should be inferred about cells with
semi permeable membranes?
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a. Substances other than water may also cross the cell membrane.
b. Substances other than water may block pores in the cell membrane.
c. Water enters the cell when placed in environments of high water concentration.
d. Water leaves the cell when placed in environments with a low concentration of
solutes. - ANSWER-c. Water enters the cell when placed in environments of high
water concentration.
Small insects can walk across the surface of calm water. Their feet push the surface
of the water down slightly, somewhat like a person walking across a trampoline, but
they do not break the surface. What is the best explanation for why this happens?
a. The insects are light enough so that they do not break the hydrogen bonds holding
the water molecules together.
b. The insects actually use their wings to hover slightly above the water's surface
and they only skim it with their feet.
c. The insects' feet are non-polar, so they are repelled by the polar water molecules
and are pushed away from the water's surface.
d. The insects are small enough to see the individual water molecules, so they are
able to step carefully from one molecule to the next. - ANSWER-a. The insects are
light enough so that they do not break the hydrogen bonds holding the water
molecules together.
A florist places a bouquet of white carnations in water containing blue dye. After a
time, the flowers turn blue. What process helped the carnations to change color?
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a. Specific heat
b. Surface tension
c. Cohesion and adhesion of water molecules.
d. Formation of covalent bonds between hydrogen and oxygen molecules. -
ANSWER-c. Cohesion and adhesion of water molecules.
The cell membrane of the red blood cell will allow water, oxygen, and carbon dioxide
to pass through. Because other substances are blocked from entering, this
membrane is called ___________________.
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a. Perforated
b. Semi-permeable
c. Non-conductive
d. Permeable - ANSWER-b. Semi-permeable
Osmosis occurs when there is a different concentration of solute molecules on each
side of the membrane. The drawing below shows a beaker containing a 30% salt