Question 1

Which of the following is created as ions diffuse across membranes?

Accepted Answer

A)  an electrical gradient 
B)  a chemical gradient 
C)  an electrochemical gradient 
D)  a biochemical gradient 
A)  an electrical gradient 
B)  a chemical gradient 
C)  an electrochemical gradient 
D)  a biochemical gradient C

Question 2

Which of the following is a function of the sterols that are found in animal cell membranes?

Accepted Answer

A)  They maintain membrane fluidity. 
B)  They facilitate ion transport. 
C)  They store cellular energy. 
D)  They increase the rate of diffusion. 
A)  They maintain membrane fluidity. 
B)  They facilitate ion transport. 
C)  They store cellular energy. 
D)  They increase the rate of diffusion. A

Question 3

Explain why the transport of molecules across the cell membrane is considered to be both specific and directional.

Accepted Answer

Transport is considered directional because only certain ions and molecules can move into the cell, while others can move only out of the cell. Transport is specific because only certain ions and molecules can actually move across the membrane.

Question 4

Cells must constantly bring in certain molecules and ions while keeping others out. What part of the cell accomplishes this function?

Accepted Answer

A)  the plasma membrane 
B)  the vesicles 
C)  the nucleus 
D)  the lysosomes 
A)  the plasma membrane 
B)  the vesicles 
C)  the nucleus 
D)  the lysosomes

Question 5

Suppose that you fuse a mouse cell and a human cell, and then treat 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, you look at the fused cell. Which of the following will you observe?

Accepted Answer

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

Question 6

Match each mechanism of cellular transport with its correct definition.
-facilitated diffusion

Accepted Answer

A) movement of a molecule from an area of high concentration to an area of lower concentration 
B) cells internalize molecules into a cell by the inward budding of vesicles possessing receptors specific to the molecule being transported 
C) movement of water from a hypotonic solution into a hypertonic solution across a selectively permeable membrane 
D) large particles are enveloped by the cell membrane and internalized 
E) a process in which liquid droplets are ingested by living cells
F)diffusion of molecules across the plasma membrane with the assistance of transport proteins 
A) movement of a molecule from an area of high concentration to an area of lower concentration 
B) cells internalize molecules into a cell by the inward budding of vesicles possessing receptors specific to the molecule being transported 
C) movement of water from a hypotonic solution into a hypertonic solution across a selectively permeable membrane 
D) large particles are enveloped by the cell membrane and internalized 
E) a process in which liquid droplets are ingested by living cells
F)diffusion of molecules across the plasma membrane with the assistance of transport proteins

Question 7

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 8

Which cell organelle helps pinocytosis and phagocytosis to occur?

Accepted Answer

A)  the endoplasmic reticulum 
B)  the lysosome 
C)  the plasma membrane 
D)  the nucleus 
A)  the endoplasmic reticulum 
B)  the lysosome 
C)  the plasma membrane 
D)  the nucleus

Question 9

What is the primary function of a cell membrane?

Accepted Answer

A)  recognizing other cells as being "like" 
B)  controlling the transport of substances into and out of cells 
C)  recognizing chemical signals from other cells 
D)  cell-cell binding 
A)  recognizing other cells as being "like" 
B)  controlling the transport of substances into and out of cells 
C)  recognizing chemical signals from other cells 
D)  cell-cell binding

Question 10

Water is a strongly polar molecule, so how does it cross the plasma membrane?

Accepted Answer

Water molecules are small enough to slip

Question 11

What are the major structural components of a cell membrane?

Accepted Answer

A)  glycolipids and cellulose 
B)  glycolipids and proteins 
C)  phospholipids and cellulose 
D)  phospholipids and proteins 
A)  glycolipids and cellulose 
B)  glycolipids and proteins 
C)  phospholipids and cellulose 
D)  phospholipids and proteins

Question 12

What does the "mosaic" part of the fluid mosaic model refer to?

Accepted Answer

A)  the membrane cholesterol 
B)  the membrane functions 
C)  the membrane proteins 
D)  the membrane phospholipids 
A)  the membrane cholesterol 
B)  the membrane functions 
C)  the membrane proteins 
D)  the membrane phospholipids

Question 13

Suppose that you fuse 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). What will the cell look like immediately after labelling?

Accepted Answer

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

Question 14

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 15

Identify the structures indicated in this drawing of a typical plasma membrane.  
-microfilament

Accepted Answer

The answer of Identify the structures indicated in this drawing...

Question 16

Match each mechanism of cellular transport with its correct definition.
-osmosis

Accepted Answer

A) movement of a molecule from an area of high concentration to an area of lower concentration 
B) cells internalize molecules into a cell by the inward budding of vesicles possessing receptors specific to the molecule being transported 
C) movement of water from a hypotonic solution into a hypertonic solution across a selectively permeable membrane 
D) large particles are enveloped by the cell membrane and internalized 
E) a process in which liquid droplets are ingested by living cells
F)diffusion of molecules across the plasma membrane with the assistance of transport proteins 
A) movement of a molecule from an area of high concentration to an area of lower concentration 
B) cells internalize molecules into a cell by the inward budding of vesicles possessing receptors specific to the molecule being transported 
C) movement of water from a hypotonic solution into a hypertonic solution across a selectively permeable membrane 
D) large particles are enveloped by the cell membrane and internalized 
E) a process in which liquid droplets are ingested by living cells
F)diffusion of molecules across the plasma membrane with the assistance of transport proteins

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.   ©1976 The Rockefeller University Press. The Journal of Cell Biology, 1976, 70:193-203. doi: 10.1083/jcb.70.1.1
-hypotonic

Accepted Answer

The answer of These micrographs of animal cells depict the...

Question 18

What do we mean when we say that facilitated diffusion is specific?

Accepted Answer

A)  A protein will transport specific molecules. 
B)  One specific integral protein per membrane is involved in facilitated diffusion. 
C)  Only specific hydrophobic molecules can be transported. 
D)  The energy molecule ATP is specifically required for transport. 
A)  A protein will transport specific molecules. 
B)  One specific integral protein per membrane is involved in facilitated diffusion. 
C)  Only specific hydrophobic molecules can be transported. 
D)  The energy molecule ATP is specifically required for transport.

Question 19

A hypertonic environment would be ideal for a healthy plant.

Accepted Answer

A) True 
 B)False

Question 20

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

Exam 4: Cell Membranes and Signaling

Which of the following is created as ions diffuse across membranes?

Which of the following is a function of the sterols that are found in animal cell membranes?

Explain why the transport of molecules across the cell membrane is considered to be both specific and directional.

Cells must constantly bring in certain molecules and ions while keeping others out. What part of the cell accomplishes this function?

Match each mechanism of cellular transport with its correct definition. -facilitated diffusion

Which statement applies to facilitated diffusion?

Which cell organelle helps pinocytosis and phagocytosis to occur?

What is the primary function of a cell membrane?

Water is a strongly polar molecule, so how does it cross the plasma membrane?

What are the major structural components of a cell membrane?

What does the "mosaic" part of the fluid mosaic model refer to?

Suppose that you fuse 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). What will the cell look like immediately after labelling?

How are exocytosis and endocytosis similar to each other?

Identify the structures indicated in this drawing of a typical plasma membrane. -microfilament

Match each mechanism of cellular transport with its correct definition. -osmosis

What do we mean when we say that facilitated diffusion is specific?

A hypertonic environment would be ideal for a healthy plant.

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?

Light and Life

The Cell: an Overview

Energy and Enzymes

Cellular Respiration

Photosynthesis

Cell Cycles

Genetic Recombination

The Chromosomal Basis of Mendelian Inheritance

Genetic Linkage, Sex-Linkage, and Other Non-Mendelian Inheritance Mechanisms

DNA Structure, Replication, and Repair

Gene Structure Expression, and Mutation

Regulation of Gene Expression

Dna Technologies

Genomes

Evolution: the Development of the Theory

Microevolution: Changes Within Populations

Speciation and Macroevolution

Systematics and Phylogenetics: Revealing the Tree of Life

Humans and Evolution

Defining Life and Its Origins

Viruses, Viroids, and Prions: Infectious Biological Particles

Bacteria and Archaea

Protists

Fungi

Plants

Animals

Conservation of Biodiversity

Population Ecology

Species Interactions and Community Ecology

Ecosystems

Animal Behaviour

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

Animal Nutrition

Gas Exchange: the Respiratory System

Internal Transport: the Circulatory System

Regulation of the Internal Environment: Water, Solutes, and Temperature

Control of Animal Processes: Endocrine Control

Animal Reproduction

Control of Animal Processes: Neural Control

Muscles, Skeletons, and Body Movements

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