Chapter 12 - practice exam General Biology (Montgomery College)

Chapter 12 - practice exam


General Biology (Montgomery
College)

, Chapter 12Biosignaling


Multiple Choice Questions

1. Molecular mechanisms of signal
transduction Page: 420 Difficulty: 2
Ans: E

Which of the following is not involved in the specificity of signal transduction?

A) Interactions between receptor and signal molecules
B) Location of receptor molecules
C) Structure of receptor molecules
D) Structure of signal molecules
E) Transmembrane transport of signal molecules by receptor molecules

2. Molecular mechanisms of signal
transduction Page: 421 Difficulty: 2
Ans: E
Scatchard analysis can provide information on:

A) enzyme cascades.
B) enzyme mechanisms.
C) gated ion channels.
D) protein phosphorylation.
E) receptor-ligand interactions.

3. General Features of Signal
Transduction Page: 422 Difficulty: 2
Ans: B
Which of the following statements concerning receptor enzymes is correct?

A) They are not usually membrane-associated proteins.
B) They contain an enzyme activity that acts upon a cytosolic substrate.
C) They contain an enzyme activity that acts upon the extracellular ligand.
D) They have a ligand-binding site on the cytosolic side of the membrane.
E) They have an active site on the extracellular side of the membrane.

4. General Features of Signal
Transduction Page: 422 Difficulty: 2
Ans: C
Guanyl cyclase receptor enzymes:

A) are all membrane-spanning proteins.
B) are examples of ligand-gated ion channels.
C) catalyze synthesis of a phosphate ester.
D) catalyze synthesis of a phosphoric acid anhydride.
E) require hydrolysis of ATP in addition to GTP.