Question 1

Dictyostelium amoebas gather to form a fruiting body in a process similar to ____.

Accepted Answer

A)   G-protein-coupled signaling
B)   quorum sensing
C)   a phosphorylation cascade
D)   paracrine signaling
E)   autocrine signaling B

Question 2

Adjacent animal cells utilize ____ to rapidly communicate with each other.

Accepted Answer

A)   gap junctions
B)   plasmodesmata
C)   hormones
D)   desmosomes
E)   neurotransmitters A

Question 3

Communication and integration of responses between simultaneously occurring cell signaling pathways is called ____.

Accepted Answer

A)   mutualistic responding
B)   effector coordination
C)   cross-talk
D)   amplification
E)   signal transduction C

Question 4

You have recently identified a molecule you believe to be a signaling molecule associated with signal transduction. All you know about this molecule is that it is hydrophilic; therefore, you expect it to interact with a receptor ____.

Accepted Answer

A)   on the cell surface
B)   within the cytoplasm of the cell
C)   in the nucleus of the cell
D)   on the cytoplasmic surface of the plasma membrane
E)   associated with the endoplasmic reticulum

Question 5

The insulin receptor is an example of a(n) ____.

Accepted Answer

A)   G-protein-coupled receptor
B)   hydrophobic receptor
C)   hormone receptor
D)   receptor tyrosine kinase
E)   ion channel receptor

Question 6

Steroid hormones are nonpolar molecules derived from cholesterol.

Accepted Answer

A) True 
 B)False

Question 7

Steroid hormones ____.

Accepted Answer

A)   are proteins
B)   include testosterone, estrogens, and cortisol
C)   never activate second messengers
D)   never alter membrane transport of ions
E)   are large nonpolar molecules

Question 8

In the process of quorum sensing, bacteria release signaling molecules in ____ concentrations as cell density ____.

Accepted Answer

A)   increasing; decreases
B)   increasing; increases
C)   decreasing; increases
D)   decreasing; decreases
E)   constant; increases

Question 9

Why is it necessary for cells to communicate with each other in a regulated way?

Accepted Answer

The answer of Why is it necessary for cells to...

Question 10

More than 60% of all prescribed drugs target ____, due to their wide physiological impact.

Accepted Answer

A)   receptor tyrosine kinases
B)   hormone receptors
C)   guanylyl cyclase
D)   ligand-gated ion channels
E)   G-protein-coupled receptors

Question 11

In the IP3/DAG pathway, what is the effector molecule?

Accepted Answer

A)   IP3
B)   DAG
C)   PIP2
D)   phospholipase C
E)   calcium

Question 12

Once activated, cAMP is quickly degraded to AMP by ____, switching off the signal pathway.

Accepted Answer

A)   adenylyl cyclase
B)   diacylglycerol
C)   phospholipase C
D)   acetylcholinesterase
E)   phosphodiesterase

Question 13

The last protein in a signaling pathway is called the ____.

Accepted Answer

A)   target protein
B)   final acceptor
C)   electron acceptor
D)   second messenger
E)   effector protein

Question 14

How do cells in the body of a multicellular organism communicate with each other?

Accepted Answer

A)   by way of signaling molecules that interact with specific receptors
B)   through long projections that directly connect cells to each other
C)   through electrical signals passed between a cell and its external environment
D)   by the transport of ions between cells in different parts of the organism
E)   by the transport of ions in water

Question 15

G-protein-coupled receptors are found in both prokaryotes and eukaryotes.

Accepted Answer

A) True 
 B)False

Question 16

During autophosphorylation, RTKs add phosphate groups to which amino acids?

Accepted Answer

A)   serine
B)   glycine
C)   threonine
D)   tryptophan
E)   tyrosine

Question 17

In general, a cell receiving a message undergoes three stages of cell signaling. What are these stages?

Accepted Answer

A)   paracrine, autocrine, and local
B)   signal reception, signal transduction, and cellular response
C)   signal reception, nucleus disintegration, and apoptosis
D)   signal reception, cellular response, and cell division
E)   the alpha, beta, and gamma

Question 18

The two major categories of extracellular signaling molecules that bind to cell surface receptors are ____.

Accepted Answer

A)   peptide hormones and steroid hormones
B)   steroid hormones and neurotransmitters
C)   neurotransmitters and vitamins
D)   growth hormones and vitamins
E)   peptide hormones and neurotransmitters

Question 19

In the liver, the enzyme glycogen phosphorylase catalyzes the breakdown of glucose.

Accepted Answer

A) True 
 B)False

Question 20

Steroid hormones, such as testosterone and estrogen, are polar signaling molecules.

Accepted Answer

A) True 
 B)False

Exam 9: Cell Communication

Dictyostelium amoebas gather to form a fruiting body in a process similar to ____.

Adjacent animal cells utilize ____ to rapidly communicate with each other.

Communication and integration of responses between simultaneously occurring cell signaling pathways is called ____.

You have recently identified a molecule you believe to be a signaling molecule associated with signal transduction. All you know about this molecule is that it is hydrophilic; therefore, you expect it to interact with a receptor ____.

The insulin receptor is an example of a(n) ____.

Steroid hormones are nonpolar molecules derived from cholesterol.

Steroid hormones ____.

In the process of quorum sensing, bacteria release signaling molecules in concentrations as cell density .

Why is it necessary for cells to communicate with each other in a regulated way?

More than 60% of all prescribed drugs target ____, due to their wide physiological impact.

In the IP3/DAG pathway, what is the effector molecule?

Once activated, cAMP is quickly degraded to AMP by ____, switching off the signal pathway.

The last protein in a signaling pathway is called the ____.

How do cells in the body of a multicellular organism communicate with each other?

G-protein-coupled receptors are found in both prokaryotes and eukaryotes.

During autophosphorylation, RTKs add phosphate groups to which amino acids?

In general, a cell receiving a message undergoes three stages of cell signaling. What are these stages?

The two major categories of extracellular signaling molecules that bind to cell surface receptors are ____.

In the liver, the enzyme glycogen phosphorylase catalyzes the breakdown of glucose.

Steroid hormones, such as testosterone and estrogen, are polar signaling molecules.