Transcript Answer

The ________ portion of the cell membrane is
responsible for the isolating functions of the membrane,
while the ________ portion regulates exchange and
communication with the environment.
1. lipid; protein
4. carbohydrate; lipid
2. cholesterol; lipid
5. nucleic acid; lipid
3. protein; cholesterol
03.01Q
The ________ portion of the cell membrane is
responsible for the isolating functions of the membrane,
while the ________ portion regulates exchange and
communication with the environment.
1. lipid; protein
4. carbohydrate; lipid
2. cholesterol; lipid
5. nucleic acid; lipid
3. protein; cholesterol
03.01A
The ________ portion of the cell membrane is
responsible for the isolating functions of the membrane,
while the ________ portion regulates exchange and
communication with the environment.
Answer:
lipid; protein
Explanation:
Lipids are not soluble in the water found both
inside and outside the cell. They serve as a barrier
to passage of most hydrophilic substances.
Proteins allow passage of some of these materials
by facilitated diffusion or active transport.
03.01E
According to the fluid mosaic model of cell
membranes, which of the following is a TRUE
statement about membrane phospholipids?
1. They move laterally along
the plane of the membrane.
2. They occur in an
uninterrupted bilayer, with
membrane proteins
restricted to the surface of
the membrane.
3. They can depart from the
membrane and become
dissolved in the surrounding
solution.
4. They have hydrophilic tails
in the interior of the
membrane.
03.02Q
According to the fluid mosaic model of cell
membranes, which of the following is a TRUE
statement about membrane phospholipids?
1. They move laterally along
the plane of the membrane.
2. They occur in an
uninterrupted bilayer, with
membrane proteins
restricted to the surface of
the membrane.
3. They can depart from the
membrane and become
dissolved in the surrounding
solution.
4. They have hydrophilic tails
in the interior of the
membrane.
03.02A
According to the fluid mosaic model of cell
membranes, which of the following is a TRUE
statement about membrane phospholipids?
Answer:
They can move laterally along the plane of
the membrane.
Explanation:
In cell membranes, phospholipids form a
bilayer with the hydrophilic portions on the
outside surfaces and the hydrophobic portion
in the interior. Proteins with hydrophobic
sections can penetrate this bilayer.
03.02E
What would continue to occur if plasma
membranes were composed solely of
phospholipids and no proteins?
1. Sugar and
amino acid entry
3. Movement of ions
through channels
2. Diffusion and
osmosis
4. Immune reactions
5. Cell adhesions
03.03Q
What would continue to occur if plasma
membranes were composed solely of
phospholipids and no proteins?
1. Sugar and
amino acid entry
3. Movement of ions
through channels
2. Diffusion and
osmosis
4. Immune reactions
5. Cell adhesions
03.03A
What would continue to occur if plasma
membranes were composed solely of
phospholipids and no proteins?
Answer:
Diffusion and osmosis
Explanation:
Without membrane proteins, the movement
of most hydrophilic substances across the
membrane (by facilitated diffusion or active
transport) would not occur. However, the
movement of substances directly through the
phospholipid bilayer (by diffusion or
osmosis) would continue.
03.03E
You fill a shallow tray with water and place a drop of red
ink in one end of the tray and a drop of green ink in the
other end. Which of the following is TRUE at equilibrium?
3. Each ink is moving down its
1. The red ink is uniformly
concentration gradient.
distributed in one half of the
tray and the green ink is
4. The concentration of each ink
uniformly distributed in the
is higher at one end of the
other half of the tray.
tray than at the other end.
2. The red and green inks are 5. No predictions can be made
both uniformly distributed
without knowing the size of
throughout the tray.
the ink molecules.
03.04Q
You fill a shallow tray with water and place a drop of red
ink in one end of the tray and a drop of green ink in the
other end. Which of the following is TRUE at equilibrium?
3. Each ink is moving down its
1. The red ink is uniformly
concentration gradient.
distributed in one half of the
tray and the green ink is
4. The concentration of each ink
uniformly distributed in the
is higher at one end of the
other half of the tray.
tray than at the other end.
2. The red and green inks are 5. No predictions can be made
both uniformly distributed
without knowing the size of
throughout the tray.
the ink molecules.
03.04A
You fill a shallow tray with water and place a drop
of red ink in one end of the tray and a drop of green
ink in the other end. Which of the following is TRUE
at equilibrium?
Answer:
The red and green inks are both uniformly
distributed throughout the tray.
Explanation:
Before and during diffusion of the ink particles, there
will be net movement of particles down the
concentration gradient. After diffusion has occurred
and equilibrium is reached, the concentration of both
ink particles will be uniform throughout the tray.
03.04E
If red blood cells are taken from the body and placed
in a hypertonic solution, what happens to the cells?
1. The cells swell
and burst because
water moves into
the cells.
3. The cells remain
unchanged due to equal
solute concentration inside
and outside the cells.
2. The cells shrivel
up because water
leaves the cells.
4. The cells remain
unchanged due to equal
water concentrations inside
and outside the cells.
03.05Q
If red blood cells are taken from the body and placed
in a hypertonic solution, what happens to the cells?
1. The cells swell
and burst because
water moves into
the cells.
3. The cells remain
unchanged due to equal
solute concentration inside
and outside the cells.
2. The cells shrivel
up because water
leaves the cells.
4. The cells remain
unchanged due to equal
water concentrations inside
and outside the cells.
03.05A
If red blood cells are taken from the body and placed
in a hypertonic solution, what happens to the cells?
Answer:
The cells shrivel up because water leaves the
cells.
Explanation:
A hypertonic solution is one in which the
solute concentration is greater than that within
the cells. Because of osmosis, water will move
from the area of lesser concentration to the
area of greater concentration: from the inside
to the outside of the cells.
03.05E
The slowest rate of diffusion of dye particles
in water will occur in which situation?
1. dye particles in water at 10°C
2. dye particles in water at 20°C
3. dye particles in water at 30°C
4. dye particles in water at 40°C
5. dye particles in water at 80°C
03.06Q
The slowest rate of diffusion of dye particles
in water will occur in which situation?
1. dye particles in water at 10°C
2. dye particles in water at 20°C
3. dye particles in water at 30°C
4. dye particles in water at 40°C
5. dye particles in water at 80°C
03.06A
The slowest rate of diffusion of dye particles
in water will occur in which situation?
Answer:
dye particles in water at 10°C
Explanation:
By definition, particles move faster at higher
temperatures. Diffusion results from the
random motion of particles, and will occur
slowest at the lowest temperature.
03.06E
Two aqueous solutions are separated by a
semipermeable membrane. Solution A is 10%
starch, and solution B is 5% starch. What will occur?
1. Water will diffuse from solution A to solution B.
2. Water will diffuse from solution B to solution A.
3. Starch will diffuse from solution A to solution B.
4. Starch will diffuse from solution B to solution A.
5. Both 2 and 4 will occur.
03.07Q
Two aqueous solutions are separated by a
semipermeable membrane. Solution A is 10%
starch, and solution B is 5% starch. What will occur?
1. Water will diffuse from solution A to solution B.
2. Water will diffuse from solution B to solution A.
3. Starch will diffuse from solution A to solution B.
4. Starch will diffuse from solution B to solution A.
5. Both 2 and 4 will occur.
03.07A
Two aqueous solutions are separated by a
semipermeable membrane. Solution A is 10%
starch, and solution B is 5% starch. What will occur?
Answer:
Water will diffuse from solution B to solution A.
Explanation:
A semipermeable membrane would not allow
the passage of starch (a large molecular
complex), but would allow osmosis, the
movement of small water molecules. Since
osmosis occurs from the lower concentration
solution to that of higher concentration, water
will diffuse from solution B to solution A.
03.07E
The cytoplasm of a certain cell, such as a
neuron, already has a high concentration of K+
ions. How can K+ ions continue to enter the cell?
1. active transport
2. facilitated diffusion
3. osmosis
4. endocytosis
5. exocytosis
03.08Q
The cytoplasm of a certain cell, such as a
neuron, already has a high concentration of K+
ions. How can K+ ions continue to enter the cell?
1. active transport
2. facilitated diffusion
3. osmosis
4. endocytosis
5. exocytosis
03.08A
The cytoplasm of a certain cell, such as a
neuron, already has a high concentration of K+
ions. How can K+ ions continue to enter the cell?
Answer:
active transport
Explanation:
The movement of the ions is against the
concentration gradient. The cell must expend
ATP energy to pump the ion into the cell
against the gradient; this is active transport.
03.08E
If you were able to use a high-powered microscope
to look inside a cell as it synthesized a colored
protein that was going to be secreted from the cell,
where would you first see the protein inside the cell?
1. Smooth endoplasmic
reticulum
2. Rough endoplasmic
reticulum
3. Golgi
4. Lysosome
5. Secretory vesicle
03.09Q
If you were able to use a high-powered microscope
to look inside a cell as it synthesized a colored
protein that was going to be secreted from the cell,
where would you first see the protein inside the cell?
1. Smooth endoplasmic
reticulum
2. Rough endoplasmic
reticulum
3. Golgi
4. Lysosome
5. Secretory vesicle
03.09A
If you were able to use a high-powered microscope
to look inside a cell as it synthesized a colored
protein that was going to be secreted from the cell,
where would you first see the protein inside the cell?
Answer:
Rough endoplasmic reticulum
Explanation:
Proteins that belong in a membrane or that are
to be secreted from the cell are synthesized on
ribosomes on the surface of the rough
endoplasmic reticulum. They are then sorted
into secretory vesicles in the Golgi.
03.09E
Individuals that have severe forms of the disease
familial hypercholesterolemia may be candidates
for treatment with gene therapy because their
disease is caused by a mutation…
1. …that is not hereditary. 3. …in a single gene, and thus can
be corrected by inserting multiple
2. …resulting from a
copies of that gene into the body.
mutant channel protein
which can readily be
4. …in a gene carried by red blood
repaired and inserted
cells, and thus which is readily
into the body.
accessible to genetic engineers.
03.10Q
Individuals that have severe forms of the disease
familial hypercholesterolemia may be candidates
for treatment with gene therapy because their
disease is caused by a mutation…
1. …that is not hereditary. 3. …in a single gene, and thus can
be corrected by inserting multiple
2. …resulting from a
copies of that gene into the body.
mutant channel protein
which can readily be
4. …in a gene carried by red blood
repaired and inserted
cells, and thus which is readily
into the body.
accessible to genetic engineers.
03.10A
Individuals that have severe forms of the disease
familial hypercholesterolemia may be candidates
for treatment with gene therapy because their
disease is caused by a mutation…
Answer:
…in a single gene, and thus can be corrected by
inserting copies of that gene into the body.
Explanation:
Genetic diseases caused by genetic defects in
multiple genes will be much harder to correct by
gene therapy because we will have to identify and
then insert a large number of corrected genes.
03.10E