Kuby Immunology 7th Edition By Judith A. Owen – Test Bank

Kuby Immunology 7th Edition By Judith A. Owen – Test Bank

Chapter 3   Receptors and Signaling: B and T-Cell Receptors

1. Which of the following types of bonds would be LEAST likely in a receptor-ligand interaction?

1. Ionic bond
2. Covalent bond
3. Hydrogen bond
4. Hydrophobic interaction
5. Ionic bond 

Answer: B

Section: Receptor-Ligand Interactions

Difficulty: 2

Hint: Most receptor-ligand interactions can be disrupted with high salt concentrations.

1. Ka, the association constant, is a measure of which of the following?

1. The concentration of unbound ligands
2. The concentration of unbound receptor
3. The affinity of receptors for ligand
4. The size of the receptor relative to the ligand
5. The number of ligands for each receptor

Answer: C

Section: Receptor-Ligand Interactions

Difficulty: 2

Hint: It is the ratio of the association rate constant over the dissociation rate constant.

1. Receptors that are multivalent tend to bind to their ligands more strongly than receptors with a single binding site.  What is the term used to describe this phenomenon?

1. 1. Avidity 
   2. Valency
   3. Affinity
   4. Magnetism
   5. None of the above

Answer: A

Section: Receptor-Ligand Interactions

Difficulty: 2

Hint: Affinity is factored into the calculation for avidity.

1. Which of the following BEST describes how cytokines are released from activated T cells?

1. Cytokines are released near where T-cell receptors are clustered.
2. T cells release cytokines on the side of the cell opposite the MTOC in order to more efficiently distribute the response around the cell.
3. T cells release cytokines evenly around the cell.
4. Cytokines are released in short bursts from pre-formed vesicles full of cytokines.
5. Cytokines are released in whatever direction the MTOC happens to be facing upon TCR ligation. 

Answer: A

Section: Receptor-Ligand Interactions

Difficulty: 1

Hint: The MTOC orients the secretory apparatus toward the T-cell receptors.

1. Receptors that dimerize upon ligand binding often contain______________in their cytoplasmic domains.

1. tyrosine kinases
2. hydrophobic regions
3. proteases
4. metal-binding regions
5. large immunoglobulin folds

Answer: A

Section: Common Strategies Used in Many Signaling Pathways

Difficulty: 1

Hint: Signaling often initiates with the addition of a phosphate.