Question 1

According to ,energy cannot be created or destroyed.

Accepted Answer

A) the second law of thermodynamics 
B) Aristotle's first principle 
C) the third law of thermodynamics 
D) the first law of thermodynamics 
A) the second law of thermodynamics 
B) Aristotle's first principle 
C) the third law of thermodynamics 
D) the first law of thermodynamics

Question 2

Many of the enzymes that control a deep- sea firefly squid's ability to produce light energy from chemical energy are located

Accepted Answer

A) within mitochondria. 
B) within chloroplasts. 
C) outside of cells. 
D) in membranes. 
A) within mitochondria. 
B) within chloroplasts. 
C) outside of cells. 
D) in membranes.

Question 3

The fluid mosaic model describes the plasma membrane as consisting of

Accepted Answer

A) carbohydrates and phospholipids that can drift in the membrane. 
B) two layers of phospholipids with cholesterol sandwiched between them. 
C) diverse proteins embedded in a phospholipid bilayer. 
D) a phospholipid bilayer with embedded carbohydrates. 
A) carbohydrates and phospholipids that can drift in the membrane. 
B) two layers of phospholipids with cholesterol sandwiched between them. 
C) diverse proteins embedded in a phospholipid bilayer. 
D) a phospholipid bilayer with embedded carbohydrates.

Question 4

Substrates bind to an enzyme's site.

Accepted Answer

A) active 
B) inhibitory 
C) phosphate 
D) allosteric 
A) active 
B) inhibitory 
C) phosphate 
D) allosteric

Question 5

The molecules responsible for membrane transport are

Accepted Answer

A) proteins. 
B) steroids. 
C) carbohydrates. 
D) phospholipids. 
A) proteins. 
B) steroids. 
C) carbohydrates. 
D) phospholipids.

Question 6

Which characteristic promoted the utilization of lipids as the first cell membrane?

Accepted Answer

A) self- assembly into a simple membrane 
B) ability to form an impermeable membrane 
C) formation of a semi- solid membrane 
D) spontaneous degradation of the intracellular environment 
A) self- assembly into a simple membrane 
B) ability to form an impermeable membrane 
C) formation of a semi- solid membrane 
D) spontaneous degradation of the intracellular environment

Question 7

Which of the following substances would have the most trouble crossing a biological membrane by diffusing through the lipid bilayer?

Accepted Answer

A) a small,nonpolar molecule such as butane (C4H10) 
B) CO2 
C) Na+ 
D) O2 
A) a small,nonpolar molecule such as butane (C4H10) 
B) CO2 
C) Na+ 
D) O2

Question 8

Inhibition of an enzyme is irreversible when

Accepted Answer

A) covalent bonds form between inhibitor and enzyme. 
B) a competitive inhibitor is involved. 
C) a noncompetitive inhibitor is involved. 
D) the shape of the enzyme is changed. 
A) covalent bonds form between inhibitor and enzyme. 
B) a competitive inhibitor is involved. 
C) a noncompetitive inhibitor is involved. 
D) the shape of the enzyme is changed.

Question 9

Which of the following statements is true among all types of passive transport?

Accepted Answer

A) Only small polar molecules are able to cross the plasma membrane. 
B) Ions never cross the plasma membrane by passive transport. 
C) The concentration gradient is the driving force. 
D) Proteins are needed to transport molecules across the membrane. 
A) Only small polar molecules are able to cross the plasma membrane. 
B) Ions never cross the plasma membrane by passive transport. 
C) The concentration gradient is the driving force. 
D) Proteins are needed to transport molecules across the membrane.

Question 10

Which of the following energy transfers is impossible in living systems?

Accepted Answer

A) chemical energy to kinetic energy 
B) heat to light energy 
C) light energy to potential energy 
D) light energy to chemical energy 
A) chemical energy to kinetic energy 
B) heat to light energy 
C) light energy to potential energy 
D) light energy to chemical energy

Question 11

Membrane phospholipids

Accepted Answer

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

Question 12

Glucose molecules provide energy to power the swimming motion of sperm.In this example,the sperm are changing

Accepted Answer

A) kinetic energy into thermal energy. 
B) chemical energy into potential energy. 
C) chemical energy into kinetic energy. 
D) kinetic energy into potential energy. 
A) kinetic energy into thermal energy. 
B) chemical energy into potential energy. 
C) chemical energy into kinetic energy. 
D) kinetic energy into potential energy.

Question 13

Relaying a message from a membrane receptor to a molecule that performs a specific function within a cell is called

Accepted Answer

A) signal transduction. 
B) selective permeability. 
C) competition. 
D) inhibition. 
A) signal transduction. 
B) selective permeability. 
C) competition. 
D) inhibition.

Question 14

A cell that neither gains nor loses water when it is immersed in a solution must be

Accepted Answer

A) metabolically inactive. 
B) hypotonic to its environment. 
C) hypertonic to its environment. 
D) isotonic to its environment. 
A) metabolically inactive. 
B) hypotonic to its environment. 
C) hypertonic to its environment. 
D) isotonic to its environment.

Question 15

A child is brought to the hospital with a fever of 107°F.Doctors immediately order an ice bath to lower the child's temperature.Which of the following statements offers the most logical explanation for this action?

Accepted Answer

A) Elevated body temperatures will increase the energy of activation needed to start various chemical reactions in the body.This will interfere with the ability of enzymes to catalyze vital chemical reactions. 
B) Elevated body temperatures cause molecules to vibrate more quickly and prevent enzymes from easily attaching to reactants.This would slow vital body reactions. 
C) Elevated body temperature will increase reaction rates in the child's cells and overload the limited number of enzymes found in the cell. 
D) Elevated body temperatures may denature enzymes.This would interfere with the cell's abilities to catalyze various reactions. 
A) Elevated body temperatures will increase the energy of activation needed to start various chemical reactions in the body.This will interfere with the ability of enzymes to catalyze vital chemical reactions. 
B) Elevated body temperatures cause molecules to vibrate more quickly and prevent enzymes from easily attaching to reactants.This would slow vital body reactions. 
C) Elevated body temperature will increase reaction rates in the child's cells and overload the limited number of enzymes found in the cell. 
D) Elevated body temperatures may denature enzymes.This would interfere with the cell's abilities to catalyze various reactions.

Question 16

Which of the following statements regarding enzymes is true?

Accepted Answer

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

Question 17

When two aqueous solutions that differ in solute concentration are placed on either side of a semipermeable membrane and osmosis is allowed to take place,the water will

Accepted Answer

A) exhibit a net movement to the side with lower free water concentration. 
B) exhibit an equal movement in both directions across the membrane. 
C) exhibit a net movement to the side with lower solute concentration. 
D) exhibit a net movement to the side with higher free water concentration. 
A) exhibit a net movement to the side with lower free water concentration. 
B) exhibit an equal movement in both directions across the membrane. 
C) exhibit a net movement to the side with lower solute concentration. 
D) exhibit a net movement to the side with higher free water concentration.

Question 18

Which of the following substances could be a cofactor?

Accepted Answer

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

Question 19

Phagocytosis is to eating as pinocytosis is to

Accepted Answer

A) drinking. 
B) osmosis. 
C) chewing. 
D) lysis. 
A) drinking. 
B) osmosis. 
C) chewing. 
D) lysis.

Question 20

The active site of an enzyme is

Accepted Answer

A) the highly changeable portion of an enzyme that adapts to fit the substrates of various reactions. 
B) the region of an enzyme that attaches to a substrate. 
C) the region of a substrate that is changed by an enzyme. 
D) the region of a product that detaches from the enzyme. 
A) the highly changeable portion of an enzyme that adapts to fit the substrates of various reactions. 
B) the region of an enzyme that attaches to a substrate. 
C) the region of a substrate that is changed by an enzyme. 
D) the region of a product that detaches from the enzyme.

Exam 5: The Working Cell

According to ,energy cannot be created or destroyed.

Many of the enzymes that control a deep- sea firefly squid's ability to produce light energy from chemical energy are located

The fluid mosaic model describes the plasma membrane as consisting of

Substrates bind to an enzyme's site.

The molecules responsible for membrane transport are

Which characteristic promoted the utilization of lipids as the first cell membrane?

Which of the following substances would have the most trouble crossing a biological membrane by diffusing through the lipid bilayer?

Inhibition of an enzyme is irreversible when

Which of the following statements is true among all types of passive transport?

Which of the following energy transfers is impossible in living systems?

Membrane phospholipids

Glucose molecules provide energy to power the swimming motion of sperm.In this example,the sperm are changing

Relaying a message from a membrane receptor to a molecule that performs a specific function within a cell is called

A cell that neither gains nor loses water when it is immersed in a solution must be

A child is brought to the hospital with a fever of 107°F.Doctors immediately order an ice bath to lower the child's temperature.Which of the following statements offers the most logical explanation for this action?

Which of the following statements regarding enzymes is true?

When two aqueous solutions that differ in solute concentration are placed on either side of a semipermeable membrane and osmosis is allowed to take place,the water will

Which of the following substances could be a cofactor?

Phagocytosis is to eating as pinocytosis is to

The active site of an enzyme is

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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