Please help! I can\'t figure out the answers to these questions. 1. Once neurona
ID: 178932 • Letter: P
Question
Please help! I can't figure out the answers to these questions.
1. Once neuronal action potential has been initiated, it becomes:
a. Self-propagating
b. Hyperpolarizing
c. Self-limiting
d. Neutralizing
2. Lectin-binding transmembrane glycoproteins on leukocytes and endothelial cells are called:
a. Integrin
b. Selectins
c. IgSF proteins
d. Cadherin
3. What allows cells to respond to an extracellular messenger molecule that does not pass freely through plasma membranes?
a. They must have ion channels.
b. They must have a lipid bilayer that allows a response.
c. They must have receptor proteins exposed on their inner plasma membrane surface.
d. They must express transmembrane receptors that specifically recognize and bind that particular messenger molecule.
4. What is the response of a receptor to the binding of a ligand to its extracellular surface?
a. It dentures.
b. The receptor relays a signal across the membrane to the receptor’s cytoplasmic domain at the inner membrane surface.
c. The receptor relays a signal elsewhere on the membrane to the receptor’s extracellular domain at the outer membrane surface.
d. It dissociates immediately from the ligand.
Explanation / Answer
Q1.
C. self-limiting
Action potential persists for only about 1ms and is self-limiting.
Q2.
B. selectins
Lectin-binding transmembrane glycoproteins on leukocytes and endothelial cells are selectins
Q3.
d. They must express transmembrane receptors that specifically recognize and bind that particular messenger molecule.