Question 1

Tight junctions prevent the movement of the extracellular matrix between cells.

Accepted Answer

A) True 
 B)False

Question 2

Plasmodesmata are not found in animal cells.

Accepted Answer

A) True 
 B)False

Question 3

Elevated cholesterol and LDL (the particles that transport cholesterol)have been strongly associated with vascular disease;what process(es)lead to the elevated levels?

Accepted Answer

A)  excessive absorption of cholesterol from the GI tract 
B)  reduced production of cholesterol by the liver 
C)  increased acceptance of cholesterol by body cells 
D)  reduced conversion of cholesterol into sex hormone receptor molecules 
A)  excessive absorption of cholesterol from the GI tract 
B)  reduced production of cholesterol by the liver 
C)  increased acceptance of cholesterol by body cells 
D)  reduced conversion of cholesterol into sex hormone receptor molecules

Question 4

When the solute concentration outside a cell is equal to the solute concentration inside the cell,the cell is in a(n)________ solution.

Accepted Answer

The answer of When the solute concentration outside a cell...

Question 5

The concentration of glucose inside a cell is higher than the concentration outside that cell,yet glucose continues to enter the cell.This is an example of

Accepted Answer

A)  passive transport. 
B)  diffusion. 
C)  active transport. 
D)  osmotic transport. 
A)  passive transport. 
B)  diffusion. 
C)  active transport. 
D)  osmotic transport.

Question 6

What best explains the double-headed arrows associated with carbon dioxide and molecular oxygen shown in the following illustration?

Accepted Answer

A)  Individual molecules are unable to cross the membrane,but they can be found in relatively large numbers on both sides. 
B)  The membrane is permeable to these small molecules and they enter or leave rapidly as their concentration gradients change. 
C)  An isotonic condition exists for each molecule,so no net movement takes place. 
D)  Homeostasis requires that surplus molecules entering the cell be rejected and returned to the outside. 
A)  Individual molecules are unable to cross the membrane,but they can be found in relatively large numbers on both sides. 
B)  The membrane is permeable to these small molecules and they enter or leave rapidly as their concentration gradients change. 
C)  An isotonic condition exists for each molecule,so no net movement takes place. 
D)  Homeostasis requires that surplus molecules entering the cell be rejected and returned to the outside.

Question 7

Which of the following would directly supply energy to an active carrier protein?

Accepted Answer

A)  starch 
B)  sugars 
C)  ATP 
D)  fatty acids 
A)  starch 
B)  sugars 
C)  ATP 
D)  fatty acids

Question 8

Which of the following signaling molecules would NOT be found in animals?

Accepted Answer

A)  auxin 
B)  insulin 
C)  adrenaline 
D)  testosterone 
A)  auxin 
B)  insulin 
C)  adrenaline 
D)  testosterone

Question 9

Osmoregulation refers to balancing water concentrations in organisms and cells.

Accepted Answer

A) True 
 B)False

Question 10

Imagine a cell needing an essential specific amino acid (one the cell cannot synthesize).What process could acquire the amino acid most quickly?

Accepted Answer

A)  Phagocytize and digest bacteria,extract the specific amino acid from the residue,and release to the cytoplasm. 
B)  Place a transporter protein in the membrane that could carry the amino acid across the membrane. 
C)  Use receptor-mediated endocytosis. 
D)  Use simple diffusion because the concentration of the needed amino acid will be zero and the gradient will always be maximized. 
A)  Phagocytize and digest bacteria,extract the specific amino acid from the residue,and release to the cytoplasm. 
B)  Place a transporter protein in the membrane that could carry the amino acid across the membrane. 
C)  Use receptor-mediated endocytosis. 
D)  Use simple diffusion because the concentration of the needed amino acid will be zero and the gradient will always be maximized.

Question 11

Soon after a certain molecule enters a cell,the cell begins producing a new type of protein.The molecule was probably a

Accepted Answer

A)  receptor molecule. 
B)  hydrophilic molecule. 
C)  carrier protein. 
D)  hydrophobic hormone. 
A)  receptor molecule. 
B)  hydrophilic molecule. 
C)  carrier protein. 
D)  hydrophobic hormone.

Question 12

The human hormone insulin is produced only by a single organ,the pancreas,yet insulin is used to move glucose from the bloodstream into cells all over the body.What aspect of hormones makes it possible for insulin to work throughout the body?

Accepted Answer

A)  Hormones are able to stop cell-to-cell communication. 
B)  Hormones all cross cell membranes,and thus can move freely throughout the body. 
C)  Hormones cause rapid cell-to-cell signaling. 
D)  Hormones are long-range signaling molecules. 
A)  Hormones are able to stop cell-to-cell communication. 
B)  Hormones all cross cell membranes,and thus can move freely throughout the body. 
C)  Hormones cause rapid cell-to-cell signaling. 
D)  Hormones are long-range signaling molecules.

Question 13

Even though the concentration of water in a cell remains constant in an isotonic solution,the random movement of water molecules during ________ requires that water be constantly moving in both directions across the plasma membrane.

Accepted Answer

The answer of Even though the concentration of water in...

Question 14

Cell signaling

Accepted Answer

A)  is always a rapid process. 
B)  can be fast or slow. 
C)  is always a slow process. 
D)  does not occur in plants. 
A)  is always a rapid process. 
B)  can be fast or slow. 
C)  is always a slow process. 
D)  does not occur in plants.

Question 15

After a sex hormone enters a target cell,it

Accepted Answer

A)  binds to the nucleus. 
B)  becomes a signaling protein. 
C)  binds to an internal receptor protein. 
D)  becomes a gene. 
A)  binds to the nucleus. 
B)  becomes a signaling protein. 
C)  binds to an internal receptor protein. 
D)  becomes a gene.

Question 16

A concentration ________ is said to exist when a molecule is more abundant in one area than it is in another.

Accepted Answer

The answer of A concentration ________ is said to exist...

Question 17

Imagine two solutions separated by a selectively permeable membrane that is impermeable to glucose.On one side of the membrane,solution A contains 10 percent glucose and on the other side,solution B contains 25 percent glucose.Which of the following is true?

Accepted Answer

A)  Solution A is hypertonic relative to solution B. 
B)  The concentration of water is greatest in solution B. 
C)  Water will move from solution A to solution B. 
D)  Glucose will diffuse from solution B to solution A. 
A)  Solution A is hypertonic relative to solution B. 
B)  The concentration of water is greatest in solution B. 
C)  Water will move from solution A to solution B. 
D)  Glucose will diffuse from solution B to solution A.

Question 18

After entering its target cell,a hydrophobic hormone binds to its intracellular receptor and then interacts with the cell's DNA,resulting in the production of a specific ________.

Accepted Answer

The answer of After entering its target cell,a hydrophobic hormone...

Question 19

The principle of cell ________ is that different cells in the same organism may have different functions.

Accepted Answer

The answer of The principle of cell ________ is that...

Question 20

A given signaling molecule can bind to several different kinds of cell surface receptors.

Accepted Answer

A) True 
 B)False

Exam 4: Cell Membranes, Transport, and Communication

Tight junctions prevent the movement of the extracellular matrix between cells.

Plasmodesmata are not found in animal cells.

Elevated cholesterol and LDL (the particles that transport cholesterol)have been strongly associated with vascular disease;what process(es)lead to the elevated levels?

When the solute concentration outside a cell is equal to the solute concentration inside the cell,the cell is in a(n)________ solution.

The concentration of glucose inside a cell is higher than the concentration outside that cell,yet glucose continues to enter the cell.This is an example of

What best explains the double-headed arrows associated with carbon dioxide and molecular oxygen shown in the following illustration?

Which of the following would directly supply energy to an active carrier protein?

Which of the following signaling molecules would NOT be found in animals?

Osmoregulation refers to balancing water concentrations in organisms and cells.

Imagine a cell needing an essential specific amino acid (one the cell cannot synthesize).What process could acquire the amino acid most quickly?

Soon after a certain molecule enters a cell,the cell begins producing a new type of protein.The molecule was probably a

The human hormone insulin is produced only by a single organ,the pancreas,yet insulin is used to move glucose from the bloodstream into cells all over the body.What aspect of hormones makes it possible for insulin to work throughout the body?

Even though the concentration of water in a cell remains constant in an isotonic solution,the random movement of water molecules during ________ requires that water be constantly moving in both directions across the plasma membrane.

Cell signaling

After a sex hormone enters a target cell,it

A concentration ________ is said to exist when a molecule is more abundant in one area than it is in another.

Imagine two solutions separated by a selectively permeable membrane that is impermeable to glucose.On one side of the membrane,solution A contains 10 percent glucose and on the other side,solution B contains 25 percent glucose.Which of the following is true?

After entering its target cell,a hydrophobic hormone binds to its intracellular receptor and then interacts with the cell's DNA,resulting in the production of a specific ________.

The principle of cell ________ is that different cells in the same organism may have different functions.

A given signaling molecule can bind to several different kinds of cell surface receptors.

The Nature of Science and the Characteristics of Life

The Chemistry of Life

Cell Structure and Internal Compartments

Energy, Metabolism, and Enzymes

Photosynthesis and Cellular Respiration

Cell Division

Cancer and Human Health

Patterns of Inheritance

Chromosomes and Human Genetics

DNA and Genes

From Gene to Protein

DNA Technology

How Evolution Works

The Origin of Species

The Evolution of Biodiversity

Biological Diversity, Bacteria, and Archaea

Protista, Plantae, and Fungi

Animalia

The Biosphere

Growth of Populations

Animal Behavior

Ecological Communities

Ecosystems

Global Change

Internal Organization and Homeostasis

Nutrition and Digestion

Circulation and Gas Exchange

Animal Hormones

Nervous and Sensory Systems

Skeletons,Muscles,and Movement

The Immune System

Reproduction and Development

Plant Structure, Nutrition, and Transport

Plant Growth and Reproduction

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