Question 1

Osmosis can be defined as

Accepted Answer

A)  the diffusion of water. 
B)  the diffusion of nonpolar molecules. 
C)  active transport. 
D)  the diffusion of a solute. 
A)  the diffusion of water. 
B)  the diffusion of nonpolar molecules. 
C)  active transport. 
D)  the diffusion of a solute.

Question 2

The transfer of a phosphate group to a molecule or compound is called

Accepted Answer

A)  carboxylation. 
B)  ionization. 
C)  phosphorylation. 
D)  hydrogenation. 
A)  carboxylation. 
B)  ionization. 
C)  phosphorylation. 
D)  hydrogenation.

Question 3

Which figure depicts an animal cell placed in a solution hypotonic to the cell?

Accepted Answer

A)  cell A 
B)  cell B 
C)  cell C 
D)  cell D 
A)  cell A 
B)  cell B 
C)  cell C 
D)  cell D

Question 4

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 5

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)  receptor-mediated endocytosis 
B)  exocytosis 
C)  diffusion 
D)  phagocytosis 
A)  receptor-mediated endocytosis 
B)  exocytosis 
C)  diffusion 
D)  phagocytosis

Question 6

Cells acquire low-density lipoproteins (LDLs) by

Accepted Answer

A)  diffusion. 
B)  receptor-mediated endocytosis. 
C)  exocytosis. 
D)  phagocytosis. 
A)  diffusion. 
B)  receptor-mediated endocytosis. 
C)  exocytosis. 
D)  phagocytosis.

Question 7

Water movement is important in urine formation in the kidneys. Urine is formed when the blood is filtered by the kidneys into kidney tubules. Three figures are presented here that relate to how the kidney tubules respond to the administration of the hormone vasopressin. The direction that water flows in these figures is from the kidney tubules back into the blood.
   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.
-Based on the data from these figures, what do you expect the urine of a person to be like when vasopressin is having an effect on the kidney tubules?

Accepted Answer

A)  The urine will be salty. 
B)  The urine will be dilute. 
C)  The urine will be concentrated. 
D)  There will be large volumes of urine. 
A)  The urine will be salty. 
B)  The urine will be dilute. 
C)  The urine will be concentrated. 
D)  There will be large volumes of urine.

Question 8

Aquaporins

Accepted Answer

A)  allow water to cross the plasma membrane via facilitated diffusion. 
B)  allow water to cross the plasma membrane against its concentration gradient. 
C)  allow for the active transport of water. 
D)  are found in all cells. 
A)  allow water to cross the plasma membrane via facilitated diffusion. 
B)  allow water to cross the plasma membrane against its concentration gradient. 
C)  allow for the active transport of water. 
D)  are found in all cells.

Question 9

If placed in tap water, an animal cell will undergo lysis, whereas a plant cell will not. What accounts for this difference?

Accepted Answer

A)  the expulsion of water by the plant cell's central vacuole 
B)  the relative impermeability of the plant cell wall to water 
C)  the fact that plant cells are isotonic to tap water 
D)  the relative inelasticity and strength of the plant cell wall 
A)  the expulsion of water by the plant cell's central vacuole 
B)  the relative impermeability of the plant cell wall to water 
C)  the fact that plant cells are isotonic to tap water 
D)  the relative inelasticity and strength of the plant cell wall

Question 10

In the lab, you use a special balloon that is permeable to water but not sucrose to make an "artificial cell." The balloon is filled with a solution of 20% sucrose and 80% water and is immersed in a beaker containing a solution of 40% sucrose and 60% water. Which of the following will occur?

Accepted Answer

A)  Water will leave the balloon. 
B)  Water will enter the balloon. 
C)  Sucrose will leave the balloon. 
D)  Sucrose will enter the balloon. 
A)  Water will leave the balloon. 
B)  Water will enter the balloon. 
C)  Sucrose will leave the balloon. 
D)  Sucrose will enter the balloon.

Question 11

Bacterial production of the enzymes needed for the synthesis of the amino acid tryptophan declines with increasing levels of tryptophan and increases as tryptophan levels decline. This is an example of

Accepted Answer

A)  competitive inhibition. 
B)  noncompetitive inhibition. 
C)  feedback inhibition. 
D)  irreversible inhibition. 
A)  competitive inhibition. 
B)  noncompetitive inhibition. 
C)  feedback inhibition. 
D)  irreversible inhibition.

Question 12

Which of the following statements regarding active transport is false?

Accepted Answer

A)  Active transport uses ATP as an energy source. 
B)  Active transport can move a solute against its concentration gradient. 
C)  Active transport requires the cell to expend energy. 
D)  Active transport is driven by the concentration gradient. 
A)  Active transport uses ATP as an energy source. 
B)  Active transport can move a solute against its concentration gradient. 
C)  Active transport requires the cell to expend energy. 
D)  Active transport is driven by the concentration gradient.

Question 13

Inhibition of an enzyme is irreversible when

Accepted Answer

A)  a competitive inhibitor is involved. 
B)  a noncompetitive inhibitor is involved. 
C)  there is an abundance of substrate. 
D)  covalent bonds form between inhibitor and enzyme. 
A)  a competitive inhibitor is involved. 
B)  a noncompetitive inhibitor is involved. 
C)  there is an abundance of substrate. 
D)  covalent bonds form between inhibitor and enzyme.

Question 14

What is true about the data in the accompanying figure?

Accepted Answer

A)  The solid line represents a reaction that has been catalyzed by an enzyme. 
B)  The dashed line represents a reaction that includes an enzyme and a cofactor. 
C)  Both lines represent endergonic reactions. 
D)  The energy of the products is higher than the energy of the reactants. 
A)  The solid line represents a reaction that has been catalyzed by an enzyme. 
B)  The dashed line represents a reaction that includes an enzyme and a cofactor. 
C)  Both lines represent endergonic reactions. 
D)  The energy of the products is higher than the energy of the reactants.

Question 15

A man with a dirty cut on his hand appears at the emergency department for treatment. In order to clean the wound, the health-care provider should use

Accepted Answer

A)  a solution of very low pH. 
B)  a solution of sterilized tap water. 
C)  a weak (low concentration) solution of salt water. 
D)  distilled water. 
A)  a solution of very low pH. 
B)  a solution of sterilized tap water. 
C)  a weak (low concentration) solution of salt water. 
D)  distilled water.

Question 16

Which of the following processes is classified as a metabolic pathway?

Accepted Answer

A)  the synthesis of a protein 
B)  water moving across a membrane via osmosis 
C)  the death and lysis of a cell 
D)  the movement of oxygen across a membrane 
A)  the synthesis of a protein 
B)  water moving across a membrane via osmosis 
C)  the death and lysis of a cell 
D)  the movement of oxygen across a membrane

Question 17

In the lab, you use a special balloon that is permeable to water but not sucrose to make an "artificial cell." The balloon is filled with a solution of 20% sucrose and 80% water and is immersed in a beaker containing a solution of 40% sucrose and 60% water. The solution in the balloon is ________ relative to the solution in the beaker.

Accepted Answer

A)  isotonic 
B)  hypotonic 
C)  hypertonic 
A)  isotonic 
B)  hypotonic 
C)  hypertonic

Question 18

Which of the following substances could be a cofactor?

Accepted Answer

A)  a protein 
B)  a polypeptide 
C)  a zinc atom 
D)  a ribosome 
A)  a protein 
B)  a polypeptide 
C)  a zinc atom 
D)  a ribosome

Question 19

How do fatty acids travel through a cell membrane?

Accepted Answer

A)  diffusion 
B)  active transport 
C)  carrier proteins 
D)  endocytosis 
A)  diffusion 
B)  active transport 
C)  carrier proteins 
D)  endocytosis

Question 20

What is the basic difference between exergonic and endergonic reactions?

Accepted Answer

A)  Exergonic reactions involve ionic bonds; endergonic reactions involve covalent bonds. 
B)  Exergonic reactions involve the breaking of bonds; endergonic reactions involve the formation of bonds. 
C)  Exergonic reactions release energy; endergonic reactions absorb it. 
D)  In exergonic reactions, the reactants have less chemical energy than the products; in endergonic reactions, the opposite is true. 
A)  Exergonic reactions involve ionic bonds; endergonic reactions involve covalent bonds. 
B)  Exergonic reactions involve the breaking of bonds; endergonic reactions involve the formation of bonds. 
C)  Exergonic reactions release energy; endergonic reactions absorb it. 
D)  In exergonic reactions, the reactants have less chemical energy than the products; in endergonic reactions, the opposite is true.

Exam 5: The Working Cell

Osmosis can be defined as

The transfer of a phosphate group to a molecule or compound is called

Which figure depicts an animal cell placed in a solution hypotonic to the cell?

Which of the following statements regarding diffusion is false?

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?

Cells acquire low-density lipoproteins (LDLs) by

Aquaporins

If placed in tap water, an animal cell will undergo lysis, whereas a plant cell will not. What accounts for this difference?

In the lab, you use a special balloon that is permeable to water but not sucrose to make an "artificial cell." The balloon is filled with a solution of 20% sucrose and 80% water and is immersed in a beaker containing a solution of 40% sucrose and 60% water. Which of the following will occur?

Bacterial production of the enzymes needed for the synthesis of the amino acid tryptophan declines with increasing levels of tryptophan and increases as tryptophan levels decline. This is an example of

Which of the following statements regarding active transport is false?

Inhibition of an enzyme is irreversible when

What is true about the data in the accompanying figure?

A man with a dirty cut on his hand appears at the emergency department for treatment. In order to clean the wound, the health-care provider should use

Which of the following processes is classified as a metabolic pathway?

Which of the following substances could be a cofactor?

How do fatty acids travel through a cell membrane?

What is the basic difference between exergonic and endergonic reactions?

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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