Question 1

You are adrift in the Atlantic Ocean and, being thirsty, drink the surrounding seawater. As a result,

Accepted Answer

A) you quench your thirst. 
B) your cells become turgid. 
C) you dehydrate yourself. 
D) your cells lyse from excessive water intake. 
A) you quench your thirst. 
B) your cells become turgid. 
C) you dehydrate yourself. 
D) your cells lyse from excessive water intake.

Question 2

When an enzyme catalyzes a reaction,

Accepted Answer

A) it lowers the activation energy of the reaction. 
B) it raises the activation energy of the reaction. 
C) it acts as a reactant. 
D) it is used once and discarded. 
A) it lowers the activation energy of the reaction. 
B) it raises the activation energy of the reaction. 
C) it acts as a reactant. 
D) it is used once and discarded.

Question 3

Which of the following processes is endergonic?

Accepted Answer

A) the burning of wood 
B) the synthesis of glucose from carbon dioxide and water 
C) the breakdown of glucose 
D) cellular respiration 
A) the burning of wood 
B) the synthesis of glucose from carbon dioxide and water 
C) the breakdown of glucose 
D) cellular respiration

Question 4

Certain cells that line the stomach synthesize a digestive enzyme and secrete it into the stomach. This enzyme is a protein. Which of the following processes could be responsible for its secretion?

Accepted Answer

A) endocytosis 
B) exocytosis 
C) diffusion 
D) pinocytosis 
A) endocytosis 
B) exocytosis 
C) diffusion 
D) pinocytosis

Question 5

In the reaction A → B + C + heat,

Accepted Answer

A) there is a net input of energy. 
B) the potential energy of the products is greater than that of the reactant. 
C) the potential energy of the products is less than that of the reactant. 
D) entropy has decreased. 
A) there is a net input of energy. 
B) the potential energy of the products is greater than that of the reactant. 
C) the potential energy of the products is less than that of the reactant. 
D) entropy has decreased.

Question 6

In a hypotonic solution, an animal cell will

Accepted Answer

A) lyse. 
B) experience turgor. 
C) neither gain nor lose water. 
D) shrivel. 
A) lyse. 
B) experience turgor. 
C) neither gain nor lose water. 
D) shrivel.

Question 7

Membrane phospholipids

Accepted Answer

A) have hydrophobic heads that face the center of the membrane and are shielded from water. 
B) have hydrophilic tails that face outward and are exposed to water. 
C) are able to drift about in the plasma membrane. 
D) remain fluid because they are tightly packed against one another. 
A) have hydrophobic heads that face the center of the membrane and are shielded from water. 
B) have hydrophilic tails that face outward and are exposed to water. 
C) are able to drift about in the plasma membrane. 
D) remain fluid because they are tightly packed against one another.

Question 8

Kinetic energy differs from chemical energy in that

Accepted Answer

A) kinetic energy is stored energy that has the potential to do work, and chemical energy is the energy of movement. 
B) kinetic energy can be converted into various forms of energy, whereas chemical energy can only be converted into heat. 
C) kinetic energy is the energy of a moving object, whereas chemical energy is the potential energy of molecules. 
D) chemical energy is a particular form of kinetic energy. 
A) kinetic energy is stored energy that has the potential to do work, and chemical energy is the energy of movement. 
B) kinetic energy can be converted into various forms of energy, whereas chemical energy can only be converted into heat. 
C) kinetic energy is the energy of a moving object, whereas chemical energy is the potential energy of molecules. 
D) chemical energy is a particular form of kinetic energy.

Question 9

A group of single cell organisms collected from the ocean was brought into the lab for examination. The lab assistant was concerned that the water had become full of toxic waste products and so added clean water to the culture. All of the organisms died, and when she looked at them under the microscope, all she could see were bits and pieces of them scattered throughout the water. What likely happened?

Accepted Answer

A) She added water that was hypotonic to the culture of organisms, and they ruptured. 
B) She added sea water to which she had added too much salt, and they ruptured. 
C) She added water isotonic to the organisms, causing too much water to move in and out of the organism, and they ruptured. 
D) She added too little salt to the sea water she added, and the organisms all lost too much water and shriveled up. 
A) She added water that was hypotonic to the culture of organisms, and they ruptured. 
B) She added sea water to which she had added too much salt, and they ruptured. 
C) She added water isotonic to the organisms, causing too much water to move in and out of the organism, and they ruptured. 
D) She added too little salt to the sea water she added, and the organisms all lost too much water and shriveled up.

Question 10

Which of the following statements regarding diffusion is false?

Accepted Answer

A) Diffusion is a result of the thermal energy of atoms and molecules. 
B) Diffusion requires no input of energy into the system. 
C) Diffusion occurs when particles spread from areas where they are less concentrated to areas where they are more concentrated. 
D) Diffusion occurs even after equilibrium is reached and no net change is apparent. 
A) Diffusion is a result of the thermal energy of atoms and molecules. 
B) Diffusion requires no input of energy into the system. 
C) Diffusion occurs when particles spread from areas where they are less concentrated to areas where they are more concentrated. 
D) Diffusion occurs even after equilibrium is reached and no net change is apparent.

Question 11

Which part of the ATP molecule breaks free of the rest when an ATP molecule is used for energy?

Accepted Answer

A) part A 
B) part B 
C) part C 
D) part D 
A) part A 
B) part B 
C) part C 
D) part D

Question 12

Which of the following statements regarding enzymes is true?

Accepted Answer

A) Enzymes are inorganic. 
B) An enzyme's function is unaffected by changes in pH. 
C) Enzymes catalyze specific reactions. 
D) All enzymes depend on protein cofactors to function. 
A) Enzymes are inorganic. 
B) An enzyme's function is unaffected by changes in pH. 
C) Enzymes catalyze specific reactions. 
D) All enzymes depend on protein cofactors to function.

Question 13

After reading the paragraph below, answer the questions that follow.
Americans spend up to $100 billion annually for bottled water (41 billion gallons). The only beverages with higher sales are carbonated soft drinks. Recent news stories have highlighted the fact that most bottled water comes from municipal water supplies (the same source as your tap water), although it may undergo an extra purification step called reverse osmosis.
Imagine two tanks that are separated by a membrane that's permeable to water, but not to the dissolved minerals present in the water. Tank A contains tap water and tank B contains the purified water. Under normal conditions, the purified water would cross the membrane to dilute the more concentrated tap water solution. In the reverse osmosis process, pressure is applied to the tap water tank to force the water molecules across the membrane into the pure water tank.
-After the reverse osmosis system has been operating for 30 minutes, the solution in tank A would

Accepted Answer

A) be hypotonic to tank B. 
B) be isotonic to tank B. 
C) be hypertonic to tank B. 
D) move by passive transport to tank B. 
A) be hypotonic to tank B. 
B) be isotonic to tank B. 
C) be hypertonic to tank B. 
D) move by passive transport to tank B.

Question 14

Plasma membranes are selectively permeable. This means that

Accepted Answer

A) anything can pass into or out of a cell as long as the membrane is intact and the cell is healthy. 
B) the plasma membrane allows some substances to enter or leave a cell more easily than others. 
C) glucose cannot enter the cell. 
D) plasma membranes must be very thick. 
A) anything can pass into or out of a cell as long as the membrane is intact and the cell is healthy. 
B) the plasma membrane allows some substances to enter or leave a cell more easily than others. 
C) glucose cannot enter the cell. 
D) plasma membranes must be very thick.

Question 15

After reading the paragraph below, answer the questions that follow.
Americans spend up to $100 billion annually for bottled water (41 billion gallons). The only beverages with higher sales are carbonated soft drinks. Recent news stories have highlighted the fact that most bottled water comes from municipal water supplies (the same source as your tap water), although it may undergo an extra purification step called reverse osmosis.
Imagine two tanks that are separated by a membrane that's permeable to water, but not to the dissolved minerals present in the water. Tank A contains tap water and tank B contains the purified water. Under normal conditions, the purified water would cross the membrane to dilute the more concentrated tap water solution. In the reverse osmosis process, pressure is applied to the tap water tank to force the water molecules across the membrane into the pure water tank.
-If you shut off the system and pressure was no longer applied to tank A, you would expect

Accepted Answer

A) the water to flow from tank A to tank B. 
B) the water to reverse flow from tank B to tank A. 
C) the water to flow in equal amounts in both directions. 
D) the water to flow against the concentration gradient. 
A) the water to flow from tank A to tank B. 
B) the water to reverse flow from tank B to tank A. 
C) the water to flow in equal amounts in both directions. 
D) the water to flow against the concentration gradient.

Question 16

Diffusion does not require the cell to expend ATP. Therefore, diffusion is considered a type of

Accepted Answer

A) exocytosis. 
B) passive transport. 
C) active transport. 
D) endocytosis. 
A) exocytosis. 
B) passive transport. 
C) active transport. 
D) endocytosis.

Question 17

A steer must eat at least 100 pounds of grain to gain less than 10 pounds of muscle tissue. This illustrates

Accepted Answer

A) the first law of thermodynamics. 
B) the second law of thermodynamics. 
C) that some energy is destroyed in every energy conversion. 
D) that energy transformations are typically 100% efficient. 
A) the first law of thermodynamics. 
B) the second law of thermodynamics. 
C) that some energy is destroyed in every energy conversion. 
D) that energy transformations are typically 100% efficient.

Question 18

Figure A. Changes in permeability of tubules in the kidney in response to the hormone vasopressin (AVP), which aids in osmoregulation.
   
Figure B. Density of aquaporins in kidney tubule cells before, during, and after administration of vasopressin.
   
Figure C. Permeability of tissues to water before, during, and after administration of vasopressin.
   
The following questions relate to these data indicating how the tubules in the kidney respond to the administration of the hormone vasopressin.
-Using the data from the graphs and what you know about membranes and metabolic pathways, predict which of the following is the likely reason why actions of aquaporins in a membrane can change so rapidly.

Accepted Answer

A) The number of aquaporins in the membrane is constant, but the pores have to be activated. 
B) Aquaporins are inserted into the membrane as needed. 
C) Aquaporins are only in cells that need to be permeable to water. 
D) Aquaporins use ATP to pump water across the membrane, and their action is limited by the metabolic pathways that produce ATP. 
A) The number of aquaporins in the membrane is constant, but the pores have to be activated. 
B) Aquaporins are inserted into the membrane as needed. 
C) Aquaporins are only in cells that need to be permeable to water. 
D) Aquaporins use ATP to pump water across the membrane, and their action is limited by the metabolic pathways that produce ATP.

Question 19

The cholesterol associated with animal cell membranes

Accepted Answer

A) is attached to membrane proteins and extends into the watery environment surrounding the cell. 
B) helps to keep phospholipids from being too close to one another. 
C) is an abnormality resulting from a diet high in cholesterol. 
D) helps solidify the membranes when the room temperature is below freezing. 
A) is attached to membrane proteins and extends into the watery environment surrounding the cell. 
B) helps to keep phospholipids from being too close to one another. 
C) is an abnormality resulting from a diet high in cholesterol. 
D) helps solidify the membranes when the room temperature is below freezing.

Question 20

A plant cell in a hypotonic solution

Accepted Answer

A) becomes turgid because of an inflow of water. 
B) bursts because of an inflow of water. 
C) shrivels because of an outflow of water. 
D) wilts because of an outflow of water. 
A) becomes turgid because of an inflow of water. 
B) bursts because of an inflow of water. 
C) shrivels because of an outflow of water. 
D) wilts because of an outflow of water.

Exam 5: The Working Cell

You are adrift in the Atlantic Ocean and, being thirsty, drink the surrounding seawater. As a result,

When an enzyme catalyzes a reaction,

Which of the following processes is endergonic?

Certain cells that line the stomach synthesize a digestive enzyme and secrete it into the stomach. This enzyme is a protein. Which of the following processes could be responsible for its secretion?

In the reaction A → B + C + heat,

In a hypotonic solution, an animal cell will

Membrane phospholipids

Kinetic energy differs from chemical energy in that

Which of the following statements regarding diffusion is false?

Which part of the ATP molecule breaks free of the rest when an ATP molecule is used for energy?

Which of the following statements regarding enzymes is true?

Plasma membranes are selectively permeable. This means that

Diffusion does not require the cell to expend ATP. Therefore, diffusion is considered a type of

A steer must eat at least 100 pounds of grain to gain less than 10 pounds of muscle tissue. This illustrates

The cholesterol associated with animal cell membranes

A plant cell in a hypotonic solution

Biology: Exploring Life

The Chemical Basis of Life

The Molecules of Cells

A Tour of the Cell

How Cells Harvest Chemical Energy

Photosynthesis: Using Light to Make Food

The Cellular Basis of Reproduction and Inheritance

Patterns of Inheritance

Molecular Biology of the Gene

How Genes Are Controlled

DNA Technology and Genomics

How Populations Evolve

The Origin of Species

Tracing Evolutionary History

Microbial Life: Prokaryotes and Protists

The Evolution of Plant and Fungal Diversity

The Evolution of Invertebrate Diversity

The Evolution of Vertebrate Diversity

Unifying Concepts of Animal Structure and Function

Nutrition and Digestion

Gas Exchange

Circulation

the Immune System

Control of Body Temperature and Water Balance

Hormones and the Endocrine System

Reproduction and Embryonic Development

Nervous Systems

the Senses

How Animals Move

Plant Structure, Growth, and Reproduction

Plant Nutrition and Transport

Control Systems in Plants

the Biosphere: an Introduction to Earths Diverse Environments

Behavioral Adaptations to the Environment

Population Ecology

Communities and Ecosystems

Conservation Biology

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