Category: Cells

Diffusion Across Membranes

%CODE1%

Diffusion Across membranes

1. Which of the following is NOT a type of passive transport?
diffusion
osmosis
endocytosis
facilitated diffusion

2. Chamber A contains 40% helium and Chamber B contains 20% helium. Chambers are connected by a tube the molecules are free to cross. Which of the following will occur?
some helium will move from chamber A to chamber B
some helium will move from chamber B to chamber A
helium will remain concentrated in chamber A
all of the helium will move into chamber B

3. What will happen to an animal cell placed in a salt water solution?
The cell will shrink
the cell will expand
the cell will burst
the cell will shrink and then expand and then shrink again

4. An animal cell placed in a hypotonic solution will:
die
take on water
lose water
divide

5. Which of the following is a type of active transport?
sodium potassium pump
endocytosis
exocytosis
all of these

6. Active transport requires:
a concentration gradient
osmosis
energy
a hypertonic solution

Score =
Correct answers:

Quiz Cells

%CODE1%

Javascript not enabled

Name: 

Cells

 

 

True/False
Indicate whether the sentence or statement is true or false.
1.
Robert Hooke observed cork cells under a microscope.
2.
Anton van Leeuwenhoek concluded that all plants are composed of cells.
3.
All living things are composed of many cells.
4.
A cell is the smallest unit that can carry on all the processes of life.
5.
Inside smaller cells, materials and information can be transported more quickly.
6.
Membranes are selectively permeable if they allow only certain substances to diffuse across them.
7.
Lysosomes carry on cellular respiration.
8.
Microtubules and microfilaments form the cytoskeleton of cells.
9.
Colonial organisms differ from single-celled organisms in that each cell cannot support its own existence.
 

Completion
Complete each sentence or statement.
10.
The statement that “cells are produced only from existing cells” is part of the ____________________.

11.
The ratio of surface area to volume puts limitations on a cell’s ____________________.

12.
Eukaryotic cells are much larger and have more specialized functions than prokaryotic cells because they contain ____________________ which take up space and carry out specialized activities.

13.
A cell with a well-defined nucleus surrounded by a nuclear membrane is called a(n) ____________________ cell.

14.
A cell membrane is said to be ____________________ permeable because it allows the passage of some solutes and not others.

15.
____________________ molecules have “heads” and “tails” and are found in the cell membrane.

16.
Scientists have discovered that cells contain smaller specialized structures known as ____________________.

17.
The spherical organelles that are the site of protein synthesis in a cell are the ____________________.

18.
The meshlike network of protein fibers that supports the shape of the cell is called the ____________________.

19.
The fluid portion of the cytoplasm is called the ____________________.

20.
Photosynthesis takes place in the ____________________ of plant cells.

 

Check Your Work     Reset

Chapter 4 Cell Structure Study Guide

%CODE1%

Javascript not enabled

 

 

Name: 

Chapter 4 Cell Structure Study Guide

 

  

Modified True/False
Indicate whether the statement is true or false.  If false, change the identified word or phrase to make the statement true.
 
 1.
Robert Hooke first observed cells by looking at a thin slice of cork under a microscope. _________________________
 


 
 2.
Mathias Schleiden concluded that cells make up every part of a plant. _________________________
 


 
 3.
Differences in the colors of cells enable different cells to perform different functions. _________________________
 


 
 4.
All cells have a cell wall that surrounds them. _________________________
 


 
 5.
All multicellular organisms are made up of prokaryotic cells. _________________________
 


 
 6.
The cells of animals are prokaryotic. _________________________
 


 
 7.
The cytoskeleton is a web of protein fibers in eukaryotic cells. _________________________
 


 
 8.
Substances made in the nucleus, such as RNA messages, move into the nucleolus by passing through nuclear pores. _________________________
 


 
 9.
Flattened, membrane-bound sacs that package and distribute proteins are called the Golgi apparatus. _________________________
 


 
 10.
Ribosomes attached to the smooth ER make proteins. _________________________
 


 
 11.
Lysosomes contain specific enzymes that break down large molecules, such as food particles. _________________________
 


 
 12.
Ribosomes are the sites of ATP production in animals. _________________________
 


 
 13.
Most of a cell’s ATP is produced in the cell’s mitochondria. _________________________
 


 
 14.
A typical animal cell contains one or more chloroplasts. _________________________
 


 
 15.
A chloroplast is an organelle that uses light energy to make sugar from carbon dioxide and water. _________________________
 


 
 16.
Prokaryotes are always multicellular organisms. _________________________
 


 
 17.
Many prokaryotes have flagella that allow them to attach to surfaces. _________________________
 


 
 18.
A tissue is a distinct group of cells that have similar structures and functions. _________________________
 


 
 19.
A leaf is made up of different tissues that work together. _________________________
 


 
 20.
In multicellular organisms, a single cell must carry out all of the organism’s activities. _________________________
 


 
 21.
A unicellular organism is composed of many individual, permanently associated cells that coordinate their activities. _________________________
 


 
 22.
Colonial organisms are unicellular organisms that can live as a connected group or survive when separated. _________________________
 


 
 23.
Some protists and most fungi have a multicellular body. _________________________
 


 
 24.
Most multicellular organisms begin as a single cell. _________________________
 


 
  

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 
 25.
Which of the following led to the discovery of cells?
a.
electricity
c.
microscopes
b.
computers
d.
calculators
 
 26.
Which of the following is part of the cell theory?
a.
All living things are made of one cell.
b.
Cells are the basic units of structure and function in organisms.
c.
Most cells arise from existing cells.
d.
Cells are nonliving units that make up organisms.
 
 27.
When the volume of a cell increases, its surface area
a.
increases at the same rate.
c.
increases at a faster rate.
b.
remains the same.
d.
increases at a slower rate.
 
 28.
Surface area is an important factor in limiting cell growth because
a.
the cell can burst if the membrane becomes too large.
b.
materials cannot enter the cell if it is too large.
c.
the cell may become too large to take in enough food and to remove enough wastes.
d.
waste products cannot leave the cell if it is too small.
 
 29.
The size to which cells can grow is limited by their
a.
location.
c.
function.
b.
structure.
d.
surface area-to-volume ratio.
 
 30.
As cell size increases, the surface area-to-volume ratio
a.
decreases.
c.
increases then decreases.
b.
increases.
d.
remains the same.
 
 31.
To function most efficiently, a cell’s size must be
a.
large.
c.
small.
b.
medium.
d.
any size.
 
 32.
Which of the following shapes would allow a cell to have the greatest surface area-to-volume ratio?
a.
sphere
c.
egg-shaped
b.
cube
d.
broad and flat
 
 33.
A cube with a side length of 6 mm has a surface area-to-volume ratio of
a.
1:1.
c.
3:1.
b.
2:1.
d.
6:1.
 
 34.
One difference between prokaryotes and eukaryotes is that prokaryotes do not have
a.
DNA.
c.
cytoplasm.
b.
a cell membrane.
d.
a nucleus.
 
 35.
Which cells have a cell membrane, cytoplasm, ribosomes, and DNA?
a.
only animal cells
c.
only eukaryotic cells
b.
only prokaryotic cells
d.
all cells
 
 36.
The genetic material that provides instructions for making proteins is
a.
DNA.
c.
cytoplasm.
b.
cytosol.
d.
a ribosome.
 
 37.
A structure within a eukaryotic cell that carries out specific activities inside the cell is called a(n)
a.
organelle.
c.
nucleus.
b.
cytoplasm.
d.
membrane.
 
 38.
Which of the following statements about prokaryotes is correct?
a.
They have a nucleus.
b.
Their evolution preceded that of eukaryotes.
c.
The organelles in their cytoplasm are surrounded by membranes.
d.
They are multicellular organisms.
 
 39.
Only eukaryotic cells have
a.
DNA.
c.
ribosomes.
b.
membrane-bound organelles.
d.
cytoplasm.
 
  
 
nar001-1.jpg
 
 40.
Refer to the illustration above. Which structure acts as a boundary between the outside environment and the inside of the cell?
a.
structure 1
c.
structure 3
b.
structure 2
d.
structure 4
 
 41.
Refer to the illustration above. Which structure immediately identifies this cell as a eukaryote?
a.
structure 1
c.
structure 3
b.
structure 2
d.
structure 4
 
 42.
Refer to the illustration above. In eukaryotic cells, DNA is found in
a.
structure 1.
c.
structure 3.
b.
structure 2.
d.
structure 5.
 
 43.
Refer to the illustration above. Structure 2 is
a.
rough endoplasmic reticulum.
c.
a mitochondrion.
b.
a Golgi apparatus.
d.
the nucleus.
 
 44.
Refer to the illustration above. Which structure produces vesicles filled with proteins?
a.
structure 1
c.
structure 4
b.
structure 2
d.
structure 5
 
 45.
Refer to the illustration above. Structure 5 is
a.
part of the endoplasmic reticulum.
c.
a mitochondrion.
b.
a Golgi apparatus.
d.
the nucleus.
 
 46.
Refer to the illustration above. The cell uses structure 3 to
a.
transport material from one part of the cell to another.
b.
package proteins so they can be stored by the cell.
c.
use light energy to make sugar.
d.
use energy from organic compounds to make ATP.
 
 47.
Refer to the illustration above. The cell shown is probably an animal cell because it
a.
has mitochondria.
c.
has a cell membrane.
b.
does not have a cell wall.
d.
does not have a nucleus.
 
 48.
Microfilaments, microtubules, and intermediate fibers are three kinds of cytoskeleton
a.
protein fibers.
c.
organelles.
b.
membranes.
d.
DNA.
 
 49.
What kind of cytoskeleton fibers could help a cell change shape to fit into a space?
a.
microfilaments
c.
intermediate fibers
b.
microtubules
d.
tubulin fibers
 
 50.
Which of the following is true of both DNA and some proteins?
a.
made in nucleus
b.
made in ribosomes
c.
must be kept separate from cytoplasm
d.
must be kept separate from nucleus
 
 51.
cell : cell membrane ::
a.
nucleus : DNA
c.
organelle : cell
b.
nucleus : nuclear envelope
d.
cell : DNA
 
 52.
The double membrane surrounding the nucleus is called the
a.
nucleolus.
c.
ribosome.
b.
nuclear wall.
d.
nuclear envelope.
 
 53.
In a cell, proteins are made on the
a.
mitochondria.
c.
nucleus.
b.
ribosomes.
d.
cell membrane.
 
 54.
Where are bound ribosomes located?
a.
suspended in the cytosol
b.
inside the nucleus
c.
attached to membranes of another organelle
d.
outside the cell membrane
 
 55.
The organelle that moves proteins and other substances through the cell is the
a.
endoplasmic reticulum.
c.
Golgi apparatus.
b.
mitochondrion.
d.
cytoplasm.
 
 56.
The organelle that modifies, sorts, and packages proteins is the
a.
endoplasmic reticulum.
c.
lysosome.
b.
ribosome.
d.
Golgi apparatus.
 
  
 
nar002-1.jpg
 
 57.
Refer to the illustration above. The structures labeled 4 are
a.
vesicles.
c.
ribosomes.
b.
lysosomes.
d.
chloroplasts.
 
 58.
Refer to the illustration above. Which structure packages proteins for distribution?
a.
structure 1
c.
structure 3
b.
structure 2
d.
structure 4
 
 59.
Refer to the illustration above. Structure 3 is a(n)
a.
mitochondrion.
c.
ribosome.
b.
endoplasmic reticulum.
d.
vesicle.
 
 60.
Plant cells have a large membrane-bound compartment in which water, waste products, and nutrients can be stored. This compartment is called the
a.
mitochondrion.
c.
Golgi apparatus.
b.
chloroplast.
d.
central vacuole.
 
 61.
A cell that requires a lot of energy might contain large numbers of
a.
chromosomes.
c.
mitochondria.
b.
vacuoles.
d.
lysosomes.
 
 62.
The organelles associated with plant photosynthesis are the
a.
mitochondria.
c.
Golgi apparatus.
b.
chloroplasts.
d.
vacuoles.
 
 63.
sunlight : chloroplasts ::
a.
chloroplasts : lysosomes
c.
organic compounds : ribosomes
b.
organic compounds : mitochondria
d.
ATP : vesicles
 
 64.
What do chloroplasts and mitochondria have in common?
a.
absorption of light energy
c.
production of ATP
b.
presence in all cells
d.
digestion of cell wastes
 
 65.
All the following are found in both plant and animal cells, except
a.
a cell wall.
c.
mitochondria.
b.
a cell membrane.
d.
endoplasmic reticulum.
 
 66.
Short, thick outgrowths that allow prokaryotes to attach to surfaces or each other are called
a.
flagella.
c.
microfilaments.
b.
microtubules.
d.
pili.
 
 67.
Which of the following is an example of a prokaryotic cell?
a.
chloroplast
c.
bacterium
b.
fungus
d.
muscle cell
 
 68.
Which of the following pairs contains unrelated items?
a.
eukaryote-plant
c.
cell wall-animal cell
b.
ribosome-protein
d.
mitochondria-ATP
 
 69.
What level of organization is the small intestine?
a.
cell
c.
organ
b.
tissue
d.
organ system
 
 70.
Which of the following statements about colonial organisms is correct?
a.
They are multicellular.
b.
Their cell activities are integrated.
c.
They are a collection of different kinds of cells.
d.
They can survive when separated.
 
  

Completion
Complete each statement.
 
  71.
All cells arise from ____________________.
 
 

 
  72.
The basic unit of structure and function in an organism is the ____________________.
 
 

 
  73.
The statement that “cells arise only from existing cells” is part of the ____________________.
 
 

 
  74.
As a cell’s size decreases, its surface area-to-volume ratio ____________________.
 
 

 
  75.
The surface area-to-volume ratio limits a cell’s ____________________.
 
 

 
  76.
Eukaryotic cells contain specialized structures called ____________________.
 
 

 
  77.
A cell with a nucleus is a(n) ____________________ cell.
 
 

 
  78.
Scientists think that ____________________ cells evolved about 1.5 billion years ago.
 
 

 
  79.
All substances that enter or leave a cell must cross the cell ____________________.
 
 

 
  80.
The ____________________ houses a cell’s DNA, which contains genetic material.
 
 

 
  81.
The organelles where protein synthesis occurs in a cell are called ____________________.
 
 

 
  82.
Prokaryotic cells have a cell ____________________ that surrounds the cell membrane.
 
 

 
  83.
Some prokaryotic cells have a ____________________ that surrounds the cell wall.
 
 

 
  84.
____________________ cells have a system of internal membranes that divides the cytoplasm into compartments.
 
 

 
  85.
The web of protein fibers that supports the shape of the cell is called the ____________________.
 
 

 
  86.
The cytoskeleton’s network of ____________________ fibers anchors cell organelles.
 
 

 
  87.
A ribosome is made of ____________________ and many proteins.
 
 

 
  88.
DNA instructions are copied as ____________________ messages.
 
 

 
  89.
Ribosomes use RNA messages to assemble ____________________.
 
 

 
  90.
The ____________________ is a structure that makes ribosome parts in the nucleus.
 
 

 
  91.
Rough endoplasmic reticulum has ____________________ attached to its surface.
 
 

 
  92.
____________________ endoplasmic reticulum has no attached ribosomes.
 
 

 
  93.
Vesicles that contain newly made proteins move through the ____________________ from the ER to the Golgi apparatus.
 
 

 
  94.
Vesicles help maintain ____________________ by storing and releasing various substances as the cell needs them.
 
 

 
  95.
Lysosomes work by fusing with other ____________________.
 
 

 
  96.
Photosynthesis takes place in the ____________________ of plant cells.
 
 

 
  97.
Both plant cells and animal cells have cell membranes. In addition, plant cells are surrounded by a(n) ____________________.
 
 

 
  98.
In multicellular organisms, similar cells group together to make ____________________.
 
 

 
  99.
A group of identical cells that can survive alone if separated are called ____________________ organisms.
 
 

 
  

Short Answer
 
  100.
Why did it take more than 150 years for scientists to appreciate the discoveries of Hook and Leeuwenhoek?
 

 
  101.
What are the three parts of the cell theory?
 

 
  102.
What happens to a cell’s surface area-to-volume ratio as the cell gets larger?
 

 
  103.
How can a large cell have a large surface area-to-volume ratio?
 

 
  104.
What is the difference in the location of DNA in a prokaryotic cell and in a eukaryotic cell?
 

 
  105.
What is the function of organelles in eukaryotic cells?
 

 
  106.
Describe the characteristics of DNA in a prokaryotic cell.
 

 
  107.
What are three kinds of cytoskeleton in eukaryotic cells?
 

 
  108.
What are three functions of the cytoskeleton?
 

 
  109.
Where are ribosome parts made and assembled?
 

 
  110.
What kind of ribosomes makes proteins that remain inside the cell?
 

 
  111.
How does the appearance of the two kinds of endoplasmic reticulum differ? What causes the difference?
 

 
  112.
What happens to the vesicle membrane of a vesicle that migrates to the cell membrane and releases proteins to the outside of the cell?
 

 
  113.
What is the function of a contractile vacuole in a protist?
 

 
  114.
Describe what happens in a protist after the cell membrane surrounds food outside the cell.
 

 
  115.
What is the difference between the energy source of chloroplasts and mitochondria? What do the two organelles have in common?
 

 
  116.
Compare the functions of flagella and pili in prokaryotes.
 

 
  117.
What are three structures present in plant cells but not in animal cells?
 

 
  118.
What are the levels of organization of cells in a multicellular organism?
 

 
  119.
How does a multicellular organism develop from a single cell?
 

 
  

Essay
 
  120.
Small cells function more efficiently than large cells do. Briefly explain why this is true, using the concept of surface area-to-volume ratio.
 

 
  121.
Describe the making of a ribosome. Include the difference between the two kinds of ribosomes.
 

 
  122.
Describe the movement of proteins through the internal membrane system of a cell.
 

 

 

 
Check Your Work     Start Over

Cell Membrane & Transport Study Guide

%CODE1%

Javascript not enabled

Name: 

Cell membrane & Transport Quiz

 

 

True/False
Indicate whether the statement is true or false.
 1.
During diffusion, molecules diffuse from a region where their concentration is low to a region where their concentration is higher, until the particles are evenly dispersed.
 2.
When the concentration of dissolved particles outside a cell is equal to the concentration of dissolved particles inside the cell, the cell solution is isotonic.
 3.
Membranes are selectively permeable if they allow only certain substances to move across them.
 4.
A cell placed in a strong salt solution would probably burst because of osmosis.
 5.
Water will diffuse out of a cell when the cell is placed in a hypertonic solution.
 6.
Osmosis is the diffusion of starch molecules through a selectively permeable membrane.
 7.
The binding of specific molecules to ion channels controls the ability of particular ions to cross the cell membrane.
 8.
To pass through a cell membrane, water requires carrier proteins.
 9.
In facilitated diffusion, carrier proteins require energy to transport substances across the cell membrane.
 10.
The transport of specific particles down their concentration gradient through a membrane by carrier proteins is known as facilitated diffusion.
 11.
Diffusion is an active process that requires a cell to expend a great deal of energy.
 12.
Diffusion through ion channels is a form of active transport.
 13.
Facilitated diffusion moves molecules and ions against their concentration gradient, while active transport moves molecules and ions down their concentration gradient.
 14.
Passive transport uses ATP to move molecules against their concentration gradient.
 15.
In active transport, energy is required to move a substance across a cell membrane.
 16.
The sodium-potassium pump requires energy to move ions across the cell membrane.
 17.
The sodium-potassium pump moves sodium ions and potassium ions against their concentration gradient.
 18.
The sodium-potassium pump transports sodium ions out of a cell while causing potassium ions to move into the cell.
 19.
The sodium-potassium pump uses ATP.
 20.
Exocytosis is a process that uses vesicles to capture substances and bring them into a cell.
 21.
Exocytosis helps the cell rid itself of wastes.
 22.
During the process of exocytosis, the cell membrane extends to engulf substances that are too big to pass through the cell membrane.
 23.
Exocytosis does not use energy to expel proteins from the cell.
 24.
Receptor proteins pump sodium ions into a cell.
 25.
Receptor proteins may cause the formation of a second messenger molecule inside a cell.
 26.
A receptor protein sends signals into a cell by transporting a specific molecule through the cell membrane.
 

Modified True/False
Indicate whether the statement is true or false.  If false, change the identified word or phrase to make the statement true.
 27.
One way that cells maintain homeostasis is by controlling the movement of substances across the cell membrane. _________________________


 28.
The cell membrane is made up of a double layer called the DNA bilayer. _________________________


 29.
A phospholipid is made up of a lipid “head” and two fatty acid “tails.” _________________________


 30.
The nonpolar tails of a phospholipid are attracted to water. _________________________


 31.
Cell-surface markers face the inside of the cell. _________________________


 32.
A concentration gradient exists when one area has a higher concentration of a substance than another area does. _________________________


 33.
The movement down a concentration gradient is called diffusion. _________________________


 34.
When the solute concentration outside a cell is equal to the solute concentration inside the cell, the cell’s environment is hypotonic. _________________________


 35.
A cell placed in a high salt solution would swell because of osmosis. _________________________


 36.
Osmosis is the diffusion of starch molecules through a selectively permeable membrane. _________________________


 37.
To pass through a cell membrane, water requires carrier proteins. _________________________


 38.
Facilitated diffusion is an active process that requires a cell to expend a great deal of energy. _________________________


 39.
Passive transport uses ATP to move molecules against their concentration gradient. _________________________


 40.
Exocytosis is a process that uses vesicles to capture substances and bring them into a cell. _________________________


 41.
Cells use exocytosis to export proteins modified by the Golgi apparatus. _________________________


 42.
Cells communicate by sending chemical signals that carry information to other cells. _________________________


 43.
Receptor proteins bind only to signals that match the specific color of the binding site. _________________________


 44.
Receptor proteins may cause the formation of a second messenger molecule inside the cell. _________________________


 

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 45.
As a result of diffusion, the concentration of many types of substances
a.
always remains greater inside a membrane.
b.
eventually becomes balanced on both sides of a membrane.
c.
always remains greater outside of a membrane.
d.
becomes imbalanced on both sides of a membrane.
nar001-1.jpg
 46.
Refer to the illustration above. The process shown is called
a.
osmosis.
c.
active transport.
b.
facilitated diffusion.
d.
diffusion.
 47.
Refer to the illustration above. The process shown is called
a.
osmosis.
c.
active transport.
b.
facilitated diffusion.
d.
diffusion.
 48.
Diffusion is the movement of a substance
a.
only through a lipid bilayer membrane.
b.
from an area of low concentration to an area of higher concentration.
c.
only in liquids.
d.
from an area of high concentration to an area of lower concentration.
 49.
The dispersal of ink in a beaker of water is an example of
a.
diffusion.
c.
active transport.
b.
osmosis.
d.
endocytosis.
 50.
The diffusion of water into or out of a cell is called
a.
solubility.
c.
selective transport.
b.
osmosis.
d.
endocytosis.
 51.
Osmosis is a type of
a.
active transport.
c.
facilitated diffusion.
b.
passive transport.
d.
endocytosis.
 52.
A cell will swell when it is placed in a(n)
a.
hypotonic solution.
c.
isotonic solution.
b.
hypertonic solution.
d.
None of the above
 53.
The interior portion of a cell membrane forms a nonpolar zone that
a.
allows polar molecules to pass through the membrane.
b.
allows food to pass through the membrane.
c.
prevents ions and most large molecules from passing through the membrane.
d.
None of the above
 54.
Ions move through ion channels by
a.
endocytosis.
c.
passive transport.
b.
diffusion.
d.
active transport.
 55.
Ion channel gates close the pores of some ion channels in response to
a.
stretching of the cell membrane.
b.
a change in electrical charge.
c.
the binding of specific molecules to the channel.
d.
All of the above
 56.
Proteins that act like selective passageways in the cell membrane are known as
a.
marker proteins.
c.
receptor proteins.
b.
channel proteins.
d.
None of the above
 57.
Transport proteins that allow ions to pass through the cell membrane are called
a.
receptor proteins.
c.
ion channels.
b.
marker proteins.
d.
None of the above
 58.
Sugar molecules cross the cell membrane by
a.
active transport.
c.
osmosis.
b.
facilitated diffusion.
d.
gated channels.
 59.
Proteins involved in facilitated diffusion are
a.
carrier proteins.
c.
Both (a) and (b)
b.
receptor proteins.
d.
None of the above
 60.
Sugar molecules can enter cells through the process of
a.
exocytosis.
c.
osmosis.
b.
facilitated diffusion.
d.
ion pumps.
 61.
Which of the following does not require energy?
a.
diffusion
c.
active transport
b.
endocytosis
d.
sodium-potassium pump
 62.
Unlike passive transport, active transport
a.
requires energy.
b.
moves substances down their concentration gradient.
c.
does not involve carrier proteins.
d.
All of the above
 63.
Both active transport and facilitated diffusion involve
a.
ATP.
b.
movement against a concentration gradient.
c.
carrier proteins.
d.
All of the above
 64.
Which of the following is a form of active transport?
a.
osmosis
c.
facilitated diffusion
b.
diffusion
d.
sodium-potassium pump
 65.
The sodium-potassium pump
a.
is a carrier protein
c.
is located in the cytoplasm of a cell.
b.
uses passive transport.
d.
transports sugar molecules.
 66.
The sodium-potassium pump usually pumps
a.
potassium ions out of the cell.
b.
sodium ions into the cell.
c.
potassium ions into the cell.
d.
only potassium ions and sugar molecules.
 67.
The sodium-potassium pump
a.
increases the concentration of sodium ions inside a cell.
b.
decreases the concentration of sodium ions inside a cell.
c.
increases the concentration of potassium ions inside a cell.
d.
Both (b) and (c)
 68.
Proteins and polysaccharides that are too large to move into a cell through diffusion or active transport move in by
a.
exocytosis.
c.
the sodium-potassium pump.
b.
endocytosis.
d.
None of the above
 69.
Molecules that are too large to be moved through the membrane can be transported into the cell by
a.
osmosis.
c.
exocytosis.
b.
endocytosis.
d.
diffusion.
 70.
Molecules that are too large to be moved across a cell membrane can be removed from the cell by
a.
diffusion.
c.
endocytosis.
b.
exocytosis.
d.
osmosis.
 71.
Ridding the cell of materials by discharging the materials in vesicles is called
a.
osmosis.
c.
exocytosis.
b.
diffusion.
d.
endocytosis.
nar002-1.jpg
 72.
Refer to the illustration above. What happens when the structure labeled A binds to the structure labeled B?
a.
Information is sent into the cell.
c.
The cell begins to undergo mitosis.
b.
Proteins enter the cell.
d.
None of the above
 73.
Refer to the illustration above. What happens when the structure labeled A binds to the structure labeled B?
a.
Information is sent into the cell.
c.
The cell begins to swell.
b.
Proteins enter the cell.
d.
Ions enter the cell.
 74.
Refer to the illustration above. The structure labeled B in the diagram is an example of a(n)
a.
channel protein.
c.
receptor protein.
b.
signal molecule.
d.
ion pump.
 75.
Signal molecules bind to
a.
carbohydrates.
c.
receptor proteins.
b.
marker proteins.
d.
transport proteins.
 76.
When a signal molecule binds to a receptor protein, the receptor protein may
a.
change the permeability of the membrane.
b.
cause the formation of a second messenger molecule.
c.
catalyze certain chemical reactions in the cell.
d.
All of the above
 77.
Which of the following transmit information into a cell by binding to signal molecules?
a.
channel proteins
c.
marker proteins
b.
receptor proteins
d.
end proteins
 78.
cell membrane : cell ::
a.
window : house
c.
door : house
b.
roof : house
d.
wall : house
 79.
Which type of molecule forms the cell membrane?
a.
protein
c.
nucleic acid
b.
phospholipid
d.
carbohydrate
 80.
Phospholipids are molecules that have
a.
one polar phosphate head and two polar fatty acid tails.
b.
one polar phosphate head and two nonpolar fatty acid tails.
c.
one polar phosphate head and one polar fatty acid tail.
d.
one nonpolar phosphate head and two polar fatty acid tails.
 81.
The interior of the lipid bilayer of a cell membrane forms a nonpolar zone that
a.
allows most polar molecules to pass through the membrane.
b.
allows food to pass through the membrane.
c.
repels ions and most polar molecules.
d.
makes the membrane permeable to most molecules.
nar004-1.jpg
 82.
Refer to the illustration above. The structure labeled A is composed of
a.
lipids.
c.
proteins.
b.
carbohydrates.
d.
DNA.
 83.
Refer to the illustration above. The structure labeled D is a(n)
a.
cell-surface marker.
c.
enzyme.
b.
receptor protein.
d.
transport protein.
 84.
Refer to the illustration above. The structure labeled C is a(n)
a.
cell-surface marker.
c.
enzyme.
b.
receptor protein.
d.
transport protein.
 85.
Proteins in the cell membrane that identify the cell are called
a.
cell-surface markers.
c.
enzymes.
b.
receptor proteins.
d.
transport proteins.
 86.
As a result of diffusion, the concentration of many types of substances
a.
always remains greater inside a membrane.
b.
eventually becomes balanced on both sides of a membrane.
c.
always remains greater outside of a membrane.
d.
becomes imbalanced on both sides of a membrane.
 87.
Diffusion is the movement of a substance
a.
only through a lipid bilayer membrane.
b.
from an area of low concentration to an area of higher concentration.
c.
only in liquids.
d.
from an area of high concentration to an area of lower concentration.
 88.
The dispersal of ink in a beaker of water is an example of
a.
diffusion.
c.
active transport.
b.
osmosis.
d.
endocytosis.
 89.
Proteins that serve as tunnels for specific substances through the lipid bilayer are
a.
cell-surface markers.
c.
receptor proteins.
b.
channel proteins.
d.
enzymes.
 90.
Sugar molecules cross the cell membrane by
a.
active transport.
c.
osmosis.
b.
facilitated diffusion.
d.
simple diffusion.
 91.
Which of the following does not require energy?
a.
diffusion
c.
active transport
b.
endocytosis
d.
sodium-potassium pump
 92.
Ions move through ion channels by
a.
endocytosis.
c.
passive transport.
b.
simple diffusion.
d.
active transport.
 93.
The diffusion of water into or out of a cell is called
a.
solubility.
c.
selective transport.
b.
osmosis.
d.
endocytosis.
 94.
Osmosis is a type of
a.
active transport.
c.
simple diffusion.
b.
passive transport.
d.
endocytosis.
 95.
How does water pass through the cell membrane?
a.
directly through the lipid bilayer
b.
through a water ion pump
c.
through water carrier proteins
d.
through channel proteins just for water
 96.
Which of the following statements about an isotonic solution and a cell is correct?
a.
The solution has the same solute concentration that the cytoplasm does.
b.
The solution has a higher solute concentration than the cytoplasm does.
c.
A cell in the solution will lose water.
d.
A cell in the solution will gain water.
 97.
Unlike passive transport, active transport
a.
requires energy.
b.
moves substances down their concentration gradient.
c.
does not involve carrier proteins.
d.
moves water across the cell membrane.
 98.
Both active transport and facilitated diffusion involve
a.
ATP.
b.
movement against a concentration gradient.
c.
carrier proteins.
d.
channel proteins.
 99.
Which of the following is a form of active transport?
a.
osmosis
c.
facilitated diffusion
b.
simple diffusion
d.
sodium-potassium pump
 100.
The sodium-potassium pump
a.
is a carrier protein.
c.
is located in the cytoplasm of a cell.
b.
uses passive transport.
d.
transports sugar molecules.
 101.
The sodium-potassium pump usually pumps
a.
potassium ions out of the cell.
b.
sodium ions into the cell.
c.
potassium ions into the cell.
d.
only potassium ions and sugar molecules.
 102.
How many potassium ions does the sodium-potassium pump move into a cell if it moves six sodium ions out of the cell?
a.
two
c.
six
b.
four
d.
eight
 103.
Proteins and polysaccharides that are too large to move into a cell through diffusion or active transport move in by
a.
exocytosis.
c.
the sodium-potassium pump.
b.
endocytosis.
d.
channel proteins.
 104.
Molecules that are too large to be moved across a cell membrane can be removed from the cell by
a.
diffusion.
c.
endocytosis.
b.
exocytosis.
d.
osmosis.
 105.
Removing materials from a cell in vesicles is called
a.
osmosis.
c.
exocytosis.
b.
diffusion.
d.
endocytosis.
 106.
Which of the following descriptions of hormones is correct?
a.
signal molecules distributed throughout the body
b.
signal molecules that affect all cells in the body
c.
target molecules that communicate through direct contact
d.
target molecules that originate outside the body
 107.
Signal molecules bind to
a.
carbohydrates.
c.
receptor proteins.
b.
marker proteins.
d.
transport proteins.
 108.
Which of the following transmit information into a cell by binding to signal molecules?
a.
channel proteins
c.
marker proteins
b.
receptor proteins
d.
signal proteins
 109.
What change takes place in the cell membrane if a signal molecule causes a transport protein to open?
a.
permeability change
c.
formation of a second messenger
b.
activation of an enzyme
d.
change in chemical reactions
 

Completion
Complete each statement.
 110.
The random motion of particles of a substance that causes the substance to move from an area of high concentration to an area of lower concentration is called ____________________.

 111.
The diffusion of ____________________ through cell membranes is called osmosis.

 112.
Substances always flow from an area of high concentration to an area of ____________________ concentration.

 113.
When the concentration of free water molecules is higher outside a cell than inside the cell, water will diffuse ____________________ the cell.

 114.
If a cell is placed in a(n) ____________________ solution, water will flow out of the cell.

 115.
If a cell is placed in a(n) ____________________ solution, water will flow into the cell.

 116.
If a cell is placed in a(n) ____________________ solution, water flows into the cell at a rate that is equal to the rate at which water flows out of the cell.

 117.
Diffusion of ions through ion channels is a form of ____________________ transport.

 118.
If the interior of a typical cell is negatively charged, ____________________ charged ions will not require energy to diffuse into the cell using an ion channel.

 119.
In facilitated diffusion, ____________________ proteins are used to transport substances down their concentration gradient.

 120.
In ____________________ ____________________, carrier proteins do not require energy to transport amino acids into a cell.

 121.
Carrier proteins ____________________ shape to transport sugars to the interior of cells.

 122.
A cell does not expend ____________________ when diffusion takes place.

 123.
Active transport requires the use of ____________________ by a cell.

 124.
The ____________________-____________________ pump transports ions against their concentration gradients.

 125.
The sodium-potassium pump uses energy supplied by ____________________.

 126.
The sodium-potassium pump prevents the accumulation of ____________________ ions inside the cell.

 127.
The movement of a substance into a cell by a vesicle is called ____________________.

nar003-1.jpg
A
B
 128.
Refer to the illustration above. The process shown in figure B is called ____________________.

 129.
Refer to the illustration above. Cells often engulf extracellular particles and fluid, as shown in figure A. This is called ____________________.

 130.
Refer to the illustration above. The process shown in figure B is called ____________________.

 131.
Refer to the illustration above. The process shown in figure A is called ____________________.

 132.
Receptor proteins can change the ____________________ of the cell membrane.

 133.
Receptor proteins may act as ____________________, catalyzing certain chemical reactions inside the cell.

 134.
In the cell membrane, proteins that transmit information into the cell by responding to signal molecules are called ____________________.

 135.
One way cells maintain homeostasis is by controlling the movement of substances across the cell ____________________.

 136.
A(n) ____________________ is a specialized lipid made of a phosphate head and two fatty acid tails.

 137.
The phosphate head of a phospholipid is attracted to water because it is ____________________.

 138.
The fatty acid tails of a phospholipid are repelled by water because they are ____________________.

 139.
The phospholipids form a barrier through which only small, ____________________ substances can pass.

 140.
Ions and most polar molecules are repelled by the ____________________ interior of the lipid bilayer.

 141.
____________________ – ____________________ markers are attached to the cell surface and have sugars attached to their protein.

 142.
Proteins that aid in moving substances into and out of cells are called ____________________ proteins.

 143.
____________________ are proteins in the cell membrane that help with important biochemical reactions inside the cell.

 144.
____________________ proteins enable a cell to sense its surroundings by binding to certain substances outside the cell.

 145.
To reach equilibrium, substances always flow from an area of high concentration to an area of ____________________ concentration.

 146.
When one area has a higher concentration than another area does, a concentration ____________________ exists.

 147.
Substances diffuse through a cell membrane either through the lipid bilayer or through ____________________ proteins.

 148.
Oxygen and carbon dioxide pass through the lipid bilayer by ____________________ diffusion.

 149.
Diffusion of ions through ion channels is a form of ____________________ transport.

 150.
Carrier proteins change ____________________ to transport substances to the interior of cells.

 151.
A cell does not expend ____________________ when diffusion takes place.

 152.
The diffusion of ____________________ through cell membranes is called osmosis.

 153.
When the concentration of free water molecules is higher outside a cell than inside the cell, water will diffuse ____________________ the cell.

 154.
If a cell is placed in a(n) ____________________ solution, water will flow out of the cell.

 155.
If a cell is placed in a(n) ____________________ solution, water will flow into the cell.

 156.
If a cell is placed in a(n) ____________________ solution, water flows into the cell at a rate that is equal to the rate at which water flows out of the cell.

 157.
Active transport requires the use of ____________________ by a cell.

 158.
The ____________________ – ____________________ pump transports ions against their concentration gradients.

 159.
The sodium-potassium pump uses energy supplied by ____________________.

 160.
The sodium-potassium pump prevents the accumulation of ____________________ ions inside the cell.

 161.
The movement of a substance into a cell by a vesicle is called ____________________.

 162.
A signaling cell produces a signal that is detected by a ____________________ cell.

 163.
Light is an environmental ____________________ for the flowering of some plants.

 164.
In the cell membrane, proteins that bind to specific signal molecules and respond are called ____________________ proteins.

 165.
Receptor proteins can change the ____________________ of the cell membrane.

 166.
Receptor proteins may act as ____________________, triggering certain chemical reactions inside the cell.

 

Short Answer
 167.
In addition to its function as a gatekeeper, what are three other functions of the cell membrane?

 168.
What makes up the lipid bilayer?

 169.
In the lipid bilayer, what causes one layer of polar heads to face the cell’s cytoplasm and the other layer of heads to face the cell’s surroundings?

 170.
What characteristic of membrane proteins causes them to be held in the cell membrane?

 171.
What are four types of proteins in cell membranes?

 172.
What exists across a cell membrane if equilibrium is not reached?

 173.
What is the difference between how a molecule crosses the cell membrane in simple diffusion and in facilitated diffusion?

 174.
What are two types of transport proteins?

 175.
Why are some water molecules not free to move across the cell membrane?

 176.
Explain why osmosis is a form of facilitated diffusion.

 177.
What specific carrier protein moves sodium ions out of a cell and potassium ions into a cell?

 178.
What is the function of the cell membrane during endocytosis?

 179.
What are hormones, how are they distributed, and what cells do they affect?

 180.
What happens to a receptor protein once it binds to a signal molecule?

 181.
How can the cell’s response to a signal cause a permeability change?

 

Check Your Work     Start Over