Activities Quiz
1.

Which of these is a receptor molecule? (Activity 11A)

question #1

A
B
C
D
E


2.

A signal-transduction pathway is initiated when a _____ binds to a receptor. (Activity 11A)

G protein
tyrosine kinase
calmodulin
signal molecule
cyclic AMP


3.

Which of these is a signal molecule? (Activity 11A)

question #3

A
B
C
D
E


4.

A signal molecule is also known as a(n) _____. (Activity 11A)

ligand
protein
initiator
key
receptor


5.

Which of these receptors is NOT a membrane receptor? (Activity 11B)

question #5

A
B
C
D
E


6.

Which of these is a G-protein-linked receptor? (Activity 11B)

question #6

A
B
C
D
E


7.

Which of these is a tyrosine-kinase receptor? (Activity 11B)

question #7

A
B
C
D
E


8.

Which of these is an ion-channel receptor? (Activity 11B)

question #8

A
B
C
D
E


9.

The binding of signal molecules to _____ results in the phosphorylation of tyrosines. (Activity 11B)

question #9

A
B
C
D
E


10.

Which of these receptor molecules would allow Na+ to flow into the cell? (Activity 11B)

question #10

A
B
C
D
E


11.

Which of these extracellular signal molecules could diffuse through a plasma membrane and bind to an intracellular receptor? (Activity 11B)

estrogen
glycerol
cellulose
glucose
starch


12.

A(n) _____ is an example of a signal molecule that can bind to an intracellular receptor and thereby cause a gene to be turned on or off. (Activity 11B)

ion
protein
carbohydrate
nucleic acid
steroid


13.

_____ is a signal molecule that binds to an intracellular receptor. (Activity 11B)

question #13

A
B
C
D
E


14.

Thyroid hormones bind to _____ receptors. (Activity 11B)

tyrosine-kinase
plasma membrane ion-channel
steroid
intracellular
G-protein-linked


15.

Which of these acts as a second messenger? (Activity 11C)

question #15

A
B
C
D
E


16.

Which of these acts as a second messenger? (Activity 11C)

G protein
G-protein-linked receptor
protein kinase
adenylyl kinase
cyclic AMP


17.

Calcium ions that act as second messengers are stored in _____. (Activity 11C)

mitochondria
peroxisomes
lysosomes
chloroplasts
endoplasmic reticula


18.

_____ catalyzes the production of _____, which then opens an ion channel that releases _____ into the cell's cytoplasm. (Activity 11C)

Adenylyl cyclase ... cyclic AMP ... Ca2+
Adenylyl cyclase ... IP3 .... Ca2+
Protein kinase ... PIP2 ... Na+
Phospholipase C ... cyclic AMP ... Ca2+
Phospholipase C ... IP3 .... Ca2+


19.

A protein kinase activating many other protein kinases is an example of _____. (Activity 11C)

amplification
sensitization
mutualism
a cellular response
deactivation


20.

The cleavage of glycogen by glycogen phosphorylase releases _____. (Activity 11D)

glucose-1-phosphate
cellulose
galactose-1-phosphate
fructose-1-phosphate
nothing: glycogen phosphorylase cannot cleave glycogen


21.

Epinephrine acts as a signal molecule that attaches to _____ receptor proteins. (Activity 11D)

intracellular
G-protein-linked
nuclear
tyrosine-kinase
ion-channel


22.

Which of these is a receptor for calcium ions? (Activity 11D)

calmodulin
PIP2
G protein
IP3
adenylyl cyclase


23.

Which of these is NOT correct? (Activity 11D)

Phospholipase C catalyzes the formation of IP3.
Tyrosine-kinase receptors consist of two polypeptides that join when activated by a signal molecule.
Ion channels are found on both the plasma membrane and the endoplasmic reticulum.
Cyclic AMP binds to calmodulin.
Kinases are enzymes that phosphorylate other molecules.


24.

A toxin that inhibits the production of GTP would interfere with the function of a signal-transduction pathway that is initiated by the binding of a signal molecule to _____ receptors. (Activity 11D)

G-protein-linked
ion-channel
intracellular
steroid
tyrosine-kinase


25.

Which of these is a logical signal-transduction pathway? (Activity 11E)

A tyrosine-kinase receptor activates adenylyl cyclase, which activates phospholipase C, which converts ATP into cyclic AMP, which binds to an intracellular enzyme that carries out a response.
An ion-channel receptor opens, allowing a steroid hormone to enter the cell; the steroid hormone then activates protein kinases that convert GTP to GDP, which binds to an intracellular enzyme that carries out a response.
An intracellular receptor activates phospholipase C, which cleaves a membrane protein to form IP3, which then activates the opening of an ER channel protein, which releases cyclic AMP into the cytoplasm, where it binds to an intracellular enzyme that carries out a response.
A G-protein-linked receptor activates G protein, which activates phospholipase C, which cleaves a membrane protein to form IP3, which binds to a calcium channel on the ER, which opens to release calcium ions into the cytoplasm, which bind to an intracellular enzyme that carries out a response.
Forget it, I can't make sense of any of these.



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2002 Pearson Education, Inc.,
publishing as Benjamin Cummings