Question 1

Which molecules will pass most easily through a cell membrane by diffusion?

Accepted Answer

A) large, hydrophilic molecules 
B) large, polar molecules 
C) small, hydrophobic molecules 
D) ionic molecules 
A) large, hydrophilic molecules 
B) large, polar molecules 
C) small, hydrophobic molecules 
D) ionic molecules

Question 2

Which of the following do carrier proteins often transport?

Accepted Answer

A) proteins 
B) steroid hormones 
C) H2O 
D) glucose and amino acids 
A) proteins 
B) steroid hormones 
C) H2O 
D) glucose and amino acids

Question 3

Which environment is ideal for plant cells, and which is best for animal cells?

Accepted Answer

A) isotonic for plant cells, and hypertonic for animal cells 
B) isotonic for plant cells, and hypotonic for animal cells 
C) hypotonic for plant cells, and isotonic for animal cells 
D) hypotonic for plant cells, and hypertonic for animal cells 
A) isotonic for plant cells, and hypertonic for animal cells 
B) isotonic for plant cells, and hypotonic for animal cells 
C) hypotonic for plant cells, and isotonic for animal cells 
D) hypotonic for plant cells, and hypertonic for animal cells

Question 4

Which statement applies to facilitated diffusion?

Accepted Answer

A) It requires ATP. 
B) It can involve either carrier proteins or channel proteins. 
C) It is nonspecific with respect to the nature of the molecules being transported. 
D) It is not dependent on a concentration gradient. 
A) It requires ATP. 
B) It can involve either carrier proteins or channel proteins. 
C) It is nonspecific with respect to the nature of the molecules being transported. 
D) It is not dependent on a concentration gradient.

Question 5

How are receptor-mediated endocytosis and pinocytosis different?

Accepted Answer

A) Receptor-mediated endocytosis transports small molecules into cells, and pinocytosis transports large molecules out of cells. 
B) Receptor-mediated endocytosis transports all molecules out of cells, and pinocytosis transports small molecules into cells. 
C) Receptor-mediated endocytosis transports large molecules into cells, and pinocytosis transports large molecules out of cells. 
D) Receptor-mediated endocytosis transports specific molecules into cells, and pinocytosis transports nonspecific liquids into cells. 
A) Receptor-mediated endocytosis transports small molecules into cells, and pinocytosis transports large molecules out of cells. 
B) Receptor-mediated endocytosis transports all molecules out of cells, and pinocytosis transports small molecules into cells. 
C) Receptor-mediated endocytosis transports large molecules into cells, and pinocytosis transports large molecules out of cells. 
D) Receptor-mediated endocytosis transports specific molecules into cells, and pinocytosis transports nonspecific liquids into cells.

Question 6

How are the membranes of animal cells in winter able to remain fluid when the weather becomes extremely cold?

Accepted Answer

A) The percentage of both unsaturated phospholipids and cholesterol increases. 
B) The percentage of saturated phospholipids in the membrane decreases. 
C) The percentage of unsaturated phospholipids in the membrane decreases. 
D) The percentage of cholesterol molecules in the membrane increases. 
A) The percentage of both unsaturated phospholipids and cholesterol increases. 
B) The percentage of saturated phospholipids in the membrane decreases. 
C) The percentage of unsaturated phospholipids in the membrane decreases. 
D) The percentage of cholesterol molecules in the membrane increases.

Question 7

When referring to membrane glycolipids and glycoproteins, what does the prefix "glyco-" indicate?

Accepted Answer

A) polar carbohydrate groups that are attached to the molecules 
B) nonpolar carbohydrate groups that are attached to the molecules 
C) the molecules that are attached to the membrane by ionic bonds 
D) the molecules that are attached to the membrane by covalent bonds 
A) polar carbohydrate groups that are attached to the molecules 
B) nonpolar carbohydrate groups that are attached to the molecules 
C) the molecules that are attached to the membrane by ionic bonds 
D) the molecules that are attached to the membrane by covalent bonds

Question 8

Which process leads to a net movement of uncharged molecules from a low concentration to a higher concentration?

Accepted Answer

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

Question 9

How are exocytosis and endocytosis similar to each other?

Accepted Answer

A) They both transport large molecules. 
B) They both transport materials into cells. 
C) They both transport materials out of cells. 
D) They both transport small molecules. 
A) They both transport large molecules. 
B) They both transport materials into cells. 
C) They both transport materials out of cells. 
D) They both transport small molecules.

Question 10

Suppose that Joe Scientist fuses a mouse cell and a human cell, and then treats the cell with specific antibodies covalently linked to fluorescent dyes (antibodies linked to mouse proteins are green; antibodies linked to human proteins are red). Forty minutes later, Joe Scientist looks at the fused cell. What will Joe Scientist observe?

Accepted Answer

A) The red and green labels will be distributed in intermingled patches. 
B) The red and green fluorescent labels will be uniformly distributed across the entire membrane. 
C) The red and green labels will flash intermittently. 
D) The cell will be half red and half green. 
A) The red and green labels will be distributed in intermingled patches. 
B) The red and green fluorescent labels will be uniformly distributed across the entire membrane. 
C) The red and green labels will flash intermittently. 
D) The cell will be half red and half green.

Question 11

In the fluid mosaic model of cell membranes, what does the "fluid" part of the model refer to?

Accepted Answer

A) the constant movement of the hydrophilic tails in the interior of the membrane 
B) the phospholipid molecules, which freely move and exchange places with other lipids within the same half of the bilayer 
C) the free movement of cholesterol molecules within the membrane 
D) a thin layer of water found sandwiched between the two layers of phospholipids 
A) the constant movement of the hydrophilic tails in the interior of the membrane 
B) the phospholipid molecules, which freely move and exchange places with other lipids within the same half of the bilayer 
C) the free movement of cholesterol molecules within the membrane 
D) a thin layer of water found sandwiched between the two layers of phospholipids

Question 12

Which term refers to the movement of a substance from an area of low concentration to an area of high concentration using energy obtained from ATP?

Accepted Answer

A) passive transport 
B) facilitated transport 
C) active transport 
D) osmosis 
A) passive transport 
B) facilitated transport 
C) active transport 
D) osmosis

Question 13

Which of the following is absolutely necessary for diffusion to occur?

Accepted Answer

A) a phospholipid bilayer 
B) a living cell 
C) a selectively permeable membrane 
D) a concentration gradient 
A) a phospholipid bilayer 
B) a living cell 
C) a selectively permeable membrane 
D) a concentration gradient

Question 14

Which type of lipid is most important in the structure of biological membranes?

Accepted Answer

A) wax 
B) cholesterol 
C) phospholipid 
D) fat 
A) wax 
B) cholesterol 
C) phospholipid 
D) fat

Question 15

Why do transmembrane proteins have domains?

Accepted Answer

A) because they have to interact with both foreign DNA and the hydrophobic core 
B) because they have to recognize cancer cells 
C) because the cell needs them in order to reproduce 
D) because they have to interact with both the aqueous environment and the hydrophobic core 
A) because they have to interact with both foreign DNA and the hydrophobic core 
B) because they have to recognize cancer cells 
C) because the cell needs them in order to reproduce 
D) because they have to interact with both the aqueous environment and the hydrophobic core

Question 16

Suppose you are comparing the outside and inside halves of a cell membrane's phospholipid bilayer. Which of the following describes the composition of the lipids on the two surfaces?

Accepted Answer

A) symmetrical but not identical composition 
B) asymmetrical composition 
C) highly random and varied composition 
D) identical composition 
A) symmetrical but not identical composition 
B) asymmetrical composition 
C) highly random and varied composition 
D) identical composition

Question 17

These micrographs of animal cells depict the effects of various aqueous environments on red blood cells placed in a hypotonic, hypertonic, or isotonic environment. Match each term to a micrograph.
-hypertonic

Accepted Answer

A)   
B)   
C)   
A)   
B)   
C)

Question 18

Which terms refer to the movement of water across a membrane from an area of lower solute concentration to a region of higher solute concentration?

Accepted Answer

A) both endocytosis and active transport 
B) both diffusion and endocytosis 
C) both active transport and osmosis 
D) both diffusion and osmosis 
A) both endocytosis and active transport 
B) both diffusion and endocytosis 
C) both active transport and osmosis 
D) both diffusion and osmosis

Question 19

Certain organisms such as the striped bass (Morone saxatilis) are able to migrate between the ocean and freshwater streams. Consider when the striped bass migrates into freshwater streams. Which of the following situations would be necessary to maintain life?

Accepted Answer

A) Water must be kept within the cells while ions are kept out. 
B) The plasma membrane of the organism must change its glycolipid composition. 
C) The plasma membrane of the organism must change its phospholipid composition. 
D) Ions must be kept within the cells while water is kept out. 
A) Water must be kept within the cells while ions are kept out. 
B) The plasma membrane of the organism must change its glycolipid composition. 
C) The plasma membrane of the organism must change its phospholipid composition. 
D) Ions must be kept within the cells while water is kept out.

Question 20

What are aquaporins?

Accepted Answer

A) spaces that transport water molecules 
B) pores made of water molecules 
C) protein channels for water transport 
D) pores found only in bacterial cells 
A) spaces that transport water molecules 
B) pores made of water molecules 
C) protein channels for water transport 
D) pores found only in bacterial cells

Exam 5: Cell Membranes and Signalling

Which molecules will pass most easily through a cell membrane by diffusion?

Which of the following do carrier proteins often transport?

Which environment is ideal for plant cells, and which is best for animal cells?

Which statement applies to facilitated diffusion?

How are receptor-mediated endocytosis and pinocytosis different?

How are the membranes of animal cells in winter able to remain fluid when the weather becomes extremely cold?

When referring to membrane glycolipids and glycoproteins, what does the prefix "glyco-" indicate?

Which process leads to a net movement of uncharged molecules from a low concentration to a higher concentration?

How are exocytosis and endocytosis similar to each other?

In the fluid mosaic model of cell membranes, what does the "fluid" part of the model refer to?

Which term refers to the movement of a substance from an area of low concentration to an area of high concentration using energy obtained from ATP?

Which of the following is absolutely necessary for diffusion to occur?

Which type of lipid is most important in the structure of biological membranes?

Why do transmembrane proteins have domains?

Suppose you are comparing the outside and inside halves of a cell membrane's phospholipid bilayer. Which of the following describes the composition of the lipids on the two surfaces?

These micrographs of animal cells depict the effects of various aqueous environments on red blood cells placed in a hypotonic, hypertonic, or isotonic environment. Match each term to a micrograph. -hypertonic

Which terms refer to the movement of water across a membrane from an area of lower solute concentration to a region of higher solute concentration?

Certain organisms such as the striped bass (Morone saxatilis) are able to migrate between the ocean and freshwater streams. Consider when the striped bass migrates into freshwater streams. Which of the following situations would be necessary to maintain life?

What are aquaporins?

Light and Life

The Cell: an Overview

Defining Life and Its Origins

Energy and Enzymes

Cellular Respiration

Photosynthesis

Cell Cycles

Genetic Recombination

Mendel, Genes, and Inheritance

Genes, Chromosomes, and Human Genetics

Dna Structure, Replication, and Organization

Gene Structure and Expression

Control of Gene Expression

Dna Technologies

Genomes and Proteomes

Evolution: the Development of the Theory

Microevolution: Changes Within Populations

Species and Macroevolution

Understanding the History of Life on Earth

Humans and Evolution

Bacteria and Archaea

Viruses, Viroids, and Prions: Infectious Biological Particles

Protists

Fungi

Plants

Diversity of Animals 1: Sponges, Radiata, Platyhelminthes, and Protostomes

Diversity of Animals 2: Deuterostomes: Vertebrates and Their Closest Relatives

Population Ecology

Population Interactions and Community Ecology

Ecosystems

Conservation of Biodiversity

Putting Selection to Work

Organization of the Plant Body

Transport in Plants

Reproduction and Development in Flowering Plants

Plant Nutrition

Plant Signals and Responses to the Environment

Introduction to Animal Organization and Physiology

Transport in Animals: the Circulatory System

Reproduction in Animals

Animal Development

Control of Animal Processes: Neural Control

Control of Animal Processes: Neural Control

Control of Animal Processes: Neural Integration

Muscles, Skeletons, and Body Movements

Animal Behaviour

Animal Nutrition

Gas Exchange: the Respiratory System

Regulating the Internal Environment

Defences Against Disease

Conservation and Evolutionary Physiology

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