practice test ch 3

Question 1

What must happen before a body cell can begin mitotic cell division?

Answer 1

Its DNA must be replicated exactly so that identical copies of the cell’s genes can be passed on to each of its offspring.

Question 2

Each daughter cell resulting from mitotic cell division has the exactly same genetic composition.

Answer 2

True

Question 3

Which of the following describes the plasma membrane?

Answer 3

the phospholipid bilayer surrounding the cell

Question 4

Which vesicular transport process occurs primarily in some white blood cells and macrophages?

Answer 4

phagocytosis

Question 5

Which of the following names the three main parts of a human cell?

Answer 5

cytoplasm, plasma membrane, and nucleus

Question 6

Which cellular organelle is seen in this figure?

Answer 6

a mitochondrion

Question 7

Which of the following would be an example of the process taking place at B?

Answer 7

the binding of a chemical messenger activating a cytoplasmic enzyme, such as kinase, that leads to specific cellular responses

Question 8

Molecule B and molecule C are expected to interact within which of the following cellular locations?

Answer 8

ribosome

Question 9

Babies with Tay-Sachs disease cannot be treated by injecting the missing enzyme into their blood because_________.

Answer 9

the enzyme functions only in lysosomes and not in the blood

Question 10

What is the genetic material at B?

Answer 10

DNA wound around histone proteins

Question 11

The movement of water across the plasma membrane can be described by all of the following EXCEPT ________.

Answer 11

carrier-mediated facilitated diffusion.

Question 12

Drinking alcohol makes the blood hypertonic. Which option best describes the consequences of this hypertonic blood?

Answer 12

Hypertonic blood draws water out of the interstitial fluid, which makes the interstitial fluid hypertonic. This, in turn, draws water out of the cells.

Question 13

Beta cells in the pancreas produce and secrete the protein hormone insulin. You would expect to see a relatively large amount of which organelles in these cells?

Answer 13

Golgi apparatus, rough endoplasmic reticulum

Question 14

Riboswitches are folded RNAs that act as switches to turn protein synthesis on or off in response to _________.

Answer 14

changes in the environment

Question 15

A cell engulfing a relatively large particle will likely utilize ________.

Answer 15

phagocytosis

Question 16

If cells are placed in a hypertonic solution containing a solute to which the membrane is impermeable, what could happen?

Answer 16

The cells will lose water and shrink.

Question 17

Why is it necessary for glucose to be pumped into the cell rather than diffusing in?

Answer 17

Glucose may have to be moved against a concentration gradient.

Question 18

Which of the following correctly states the functions of the rough endoplasmic reticulum?

Answer 18

synthesis of the cell’s membranes

Question 19

synthesis of the cell’s membranes

Answer 19

They are whiplike, motile cellular extensions that occur in large numbers on the exposed surfaces of certain cells.

Question 20

In their resting state, all body cells exhibit a resting membrane potential; therefore, all cells are polarized.

Answer 20

T

Question 21

The nucleolus __________.

Answer 21

is the site of ribosome assembly in a cell

Question 22

Each number above molecule B refers to a codon. If an RNA codon was UAG, what would the corresponding DNA codon be?

Answer 22

ATC

Question 23

Mitosis ________.

Answer 23

is division of the genetic material within the nucleus

Question 24

Which of the following statements is true?

Answer 24

During exocytosis, substances from inside the cell are moved outside.

Question 25

The RNA responsible for bringing the amino acids to the ribosome for protein formation is ________.

Answer 25

tRNA

Question 26

Which of the following structures would aid a cell in allowing more nutrients to be absorbed by the cell?

Answer 26

microvilli

Question 27

Which transport process is the main mechanism for the movement of most macromolecules by body cells?

Answer 27

receptor-mediated endocytosis

Question 28

You observe a small, nonpolar molecule near a membrane. How would this molecule likely transport across the membrane?

Answer 28

simple diffusion

Question 29

How do unsaturated phospholipid fatty acid tails affect plasma membrane fluidity?

Answer 29

More unsaturated fatty acids means less tightly packed phospholipids, resulting in greater membrane fluidity.

Question 30

What is a function of the enzyme indicated by structure A?

Answer 30

breaking the bonds between complementary base pairs

Question 31

Which of the following is LEAST like the other three?

Answer 31

cytoplasm

Question 32

Which of the following is not a factor that binds cells together?

Answer 32

glycolipids in the glycocalyx

Question 33

What is the difference between active and passive transport across the plasma membrane?

Answer 33

Active transport is ATP dependent, whereas passive transport uses only the kinetic energy of the particles for movement across the plasma membrane.

Question 34

What is the force driving all of these transport mechanisms?

Answer 34

diffusion down a concentration gradient

Question 35

The structure at letter C is located within what area of this structure?

Answer 35

the matrix

Question 36

Which letter is pointing to an mRNA molecule?

Answer 36

B

Question 37

Aquaporins are believed to be present in red blood cells and kidney tubules, but not in any other cells in the body.

Answer 37

F

Question 38

Which of these is an inclusion, not an organelle?

Answer 38

melanin

Question 39

Which of the following is NOT a function of lysosomes?

Answer 39

help in the formation of cell membranes

Question 40

Which of the following is a component of the plasma membrane that creates a chemical barrier between the inside and the outside of the cell?

Answer 40

phospholipids

Question 41

Colchicine is a drug that can prevent the formation of microtubules. Which is the most likely affect colchicine would have on cell division?

Answer 41

It will arrest mitosis by preventing the formation of spindle microtubules.

Question 42

If the nucleotide or base sequence of the DNA strand used as a template for messenger RNA synthesis is ACGTT, then what would be the sequence of bases in the corresponding mRNA?

Answer 42

UGCAA

Question 43

A red blood cell placed in pure water would ________.

Answer 43

swell and burst

Question 44

What is the specific role of the enzyme indicated by B during the formation of the new DNA strands?

Answer 44

joining the nucleotides that form the new DNA strand

Question 45

The membrane-bound compartment indicated by structure D contains which of the following?

Answer 45

hydrolytic enzymes

Question 46

Osmosis is the passive movement of water but it follows almost completely opposite laws of physics when compared to the diffusion of ions or other small particles

Answer 46

F

Question 47

Introns represent a genome scrap yard that provides DNA segments for genome evolution and a variety of small RNA molecules.

Answer 47

True

Question 48

Which of the following will NOT speed up the net rate of diffusion for glucose into a cell?

Answer 48

Decreasing the number of phospholipids in the plasma membrane

Question 49

Which set of membrane proteins in the figure depicts the transport of solute molecules across the membrane?

Answer 49

A