Question 1

If red blood cells are taken from the body and placed in a hypertonic solution, what happens to the cells?

Accepted Answer

A) The cells swell and burst because water moves into them. 
B) The cells shrivel up because water leaves them. 
C) The cells remain unchanged due to equal solute concentrations inside and outside the cells. 
D) The cells remain unchanged due to equal water concentrations inside and outside the cells. 
E) They become white blood cells. 
A) The cells swell and burst because water moves into them. 
B) The cells shrivel up because water leaves them. 
C) The cells remain unchanged due to equal solute concentrations inside and outside the cells. 
D) The cells remain unchanged due to equal water concentrations inside and outside the cells. 
E) They become white blood cells.

Question 2

For diffusion to occur, there must be:

Accepted Answer

A) a membrane. 
B) a gradient. 
C) water. 
D) ATP. 
A) a membrane. 
B) a gradient. 
C) water. 
D) ATP.

Question 3

Suppose that plasma membranes were single layers of phospholipids with heads facing the external environment. The interior of this hypothetical cell would have to be:

Accepted Answer

A) hydrophilic only. 
B) hydrophobic only. 
C) polar only. 
D) nonpolar only. 
E) hydrophobic and nonpolar. 
A) hydrophilic only. 
B) hydrophobic only. 
C) polar only. 
D) nonpolar only. 
E) hydrophobic and nonpolar.

Question 4

The rate of facilitated diffusion of a molecule across a membrane will increase as the concentration gradient of the molecule across the membrane increases to a certain point. Eventually, an increase in the concentration of the molecule will not cause any further increase in facilitated diffusion. This is because:

Accepted Answer

A) facilitated diffusion requires ATP energy. 
B) as the concentration gradient increases, molecules interfere with one another. 
C) there are a limited number of carrier proteins in the membrane. 
D) the increased concentration gradient causes a situation far from equilibrium. 
E) the diffusion constant depends on the concentration gradient. 
A) facilitated diffusion requires ATP energy. 
B) as the concentration gradient increases, molecules interfere with one another. 
C) there are a limited number of carrier proteins in the membrane. 
D) the increased concentration gradient causes a situation far from equilibrium. 
E) the diffusion constant depends on the concentration gradient.

Question 5

Why is the biological membrane said to be selectively permeable?

Accepted Answer

It allows only some

Question 6

The slowest rate of diffusion of dye particles in water will occur at:

Accepted Answer

A) 10°C. 
B) 20°C. 
C) 30°C. 
D) 60°C. 
A) 10°C. 
B) 20°C. 
C) 30°C. 
D) 60°C.

Question 7

Carbon dioxide crosses the plasma membrane by simple diffusion. The rate at which carbon dioxide enters the cell is determined by the:

Accepted Answer

A) concentration of carbon dioxide on each side of the membrane. 
B) amount of energy being produced by the cell. 
C) amount of transport protein in the membrane. 
D) amount of carbon dioxide outside of the cell. 
E) amount of oxygen being exported from the cell. 
A) concentration of carbon dioxide on each side of the membrane. 
B) amount of energy being produced by the cell. 
C) amount of transport protein in the membrane. 
D) amount of carbon dioxide outside of the cell. 
E) amount of oxygen being exported from the cell.

Question 8

Compare and contrast facilitated diffusion and active transport.

Accepted Answer

Both require membrane transport proteins

Question 9

Within the fluid mosaic of a plasma membrane, what is the role of transport and channel proteins?

Accepted Answer

A) They prevent the passage of amino acids. 
B) They permit salts and sugars to move through the plasma membrane. 
C) They may set off cellular changes such as cell division or hormone secretion. 
D) They are cell-surface attachment sites. 
E) They identify the cell. 
A) They prevent the passage of amino acids. 
B) They permit salts and sugars to move through the plasma membrane. 
C) They may set off cellular changes such as cell division or hormone secretion. 
D) They are cell-surface attachment sites. 
E) They identify the cell.

Question 10

Specialized cell junctions include all of the following EXCEPT:

Accepted Answer

A) gap junctions. 
B) tight junctions. 
C) desmosomes. 
D) phospholipases. 
A) gap junctions. 
B) tight junctions. 
C) desmosomes. 
D) phospholipases.

Question 11

Compare and contrast osmosis and simple diffusion.

Accepted Answer

Both are passive processes. However, osm

Question 12

Which of the following requires adenosine triphosphate?

Accepted Answer

A) simple diffusion 
B) facilitated diffusion 
C) active transport 
D) osmosis 
A) simple diffusion 
B) facilitated diffusion 
C) active transport 
D) osmosis

Question 13

Osmosis moves water from a region of:

Accepted Answer

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. 
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.

Question 14

Which of the following types of membrane proteins are responsible for facilitated diffusion?

Accepted Answer

A) transport proteins 
B) recognition proteins 
C) enzymes 
D) receptor proteins 
E) attachment proteins 
A) transport proteins 
B) recognition proteins 
C) enzymes 
D) receptor proteins 
E) attachment proteins

Question 15

Which of the following types of membrane proteins are responsible for conveying external messages such as those sent by a hormone signal?

Accepted Answer

A) transport proteins 
B) recognition proteins 
C) enzymes 
D) receptor proteins 
E) attachment proteins 
A) transport proteins 
B) recognition proteins 
C) enzymes 
D) receptor proteins 
E) attachment proteins

Question 16

Solutions that cause water to enter cells by osmosis are called:

Accepted Answer

A) hypertonic. 
B) isotonic. 
C) hypotonic. 
D) permeable. 
E) hydrophilic. 
A) hypertonic. 
B) isotonic. 
C) hypotonic. 
D) permeable. 
E) hydrophilic.

Exam 5: Cell Membrane Structure and Function

If red blood cells are taken from the body and placed in a hypertonic solution, what happens to the cells?

For diffusion to occur, there must be:

Suppose that plasma membranes were single layers of phospholipids with heads facing the external environment. The interior of this hypothetical cell would have to be:

Why is the biological membrane said to be selectively permeable?

The slowest rate of diffusion of dye particles in water will occur at:

Carbon dioxide crosses the plasma membrane by simple diffusion. The rate at which carbon dioxide enters the cell is determined by the:

Compare and contrast facilitated diffusion and active transport.

Within the fluid mosaic of a plasma membrane, what is the role of transport and channel proteins?

Specialized cell junctions include all of the following EXCEPT:

Compare and contrast osmosis and simple diffusion.

Which of the following requires adenosine triphosphate?

Osmosis moves water from a region of:

Which of the following types of membrane proteins are responsible for facilitated diffusion?

Which of the following types of membrane proteins are responsible for conveying external messages such as those sent by a hormone signal?

Solutions that cause water to enter cells by osmosis are called:

An Introduction to Life on Earth

Atoms, Molecules, and Life

Biological Molecules

Cell Structure and Function

Energy Flow in the Life of a Cell

Capturing Solar Energy: Photosynthesis

Harvesting Energy: Glycolysis and Cellular Respiration

The Continuity of Life: Cellular Reproduction

Patterns of Inheritance

Dna: the Molecule of Heredity

Gene Expression and Regulation

Biotechnology

Principles of Evolution

How Populations Evolve

The Origin of Species

The History of Life

Systematics: Seeking Order Amidst Diversity

The Diversity of Prokaryotes and Viruses

The Diversity of Protists

The Diversity of Plants

The Diversity of Fungi

Animal Diversity I: Invertebrates

Animal Diversity Ii: Vertebrates

Animal Behavior

Population Growth and Regulation

Community Interactions

How Do Ecosystems Work

Earths Diverse Ecosystems

Conserving Earths Biodiversity

Homeostasis and the Organization of the Animal Body

Circulation

Respiration

Nutrition and Digestion

The Urinary System

Defenses Against Disease

Chemical Control of the Animal Body: the Endocrine System

The Nervous System

The Senses

Action and Support: the Muscles and Skeleton

Animal Reproduction

Animal Development

Plant Anatomy and Nutrient Transport

Plant Reproduction and Development

Plant Responses to the Environment

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