Question

Histamine is a chemical substance released in inflammatory and allergic responses. The histamine H1 receptor on target cells is a G protein-coupled receptor that activates phospholipase C in response to the binding of histamine. Which statements are true about the binding of histamine to the histamine H1 receptor? Select all that apply.
a. Histamine binds extracellularly to the H1 receptor.
b. When histamine binds to the H1 receptor, the receptor undergoes a conformation change and binds the inactive G protein.
c. Once the G protein is active, it binds to the enzyme phospholipase C, activating it.
d. Histamine is likely hydrophilic.

Answer 1

Answer:

All of the above statements are right regarding histamine binding with H1 receptor.

Explanation:

Histamine when comes in contact with a cell that it targeted, it started binding extracellular with its receptor H1. This binding leads to a change in the receptor’s shape. After the change occurs in the receptor, the G protein is allowed to bind with H1.

The GDP molecule is then displaced with GTP and activates the protein G. It then binds to the enzyme C and this enzyme causes a response from the cell. It is also hydrophilic.