Question

What are the main types of indirect signaling, and what is the primary feature that distinguishes them?

Answer 1

Indirect signalling is a type of signalling in which signals are sent to distant target cells usually the target cells are far off
from the signal originating place.

The main types of indirect signalling are of three types. The primary feature which distinguishes them is the mode of transport of signal molecule and interaction with the target cell. They are:
1. Signalling through receptor binding. In this type of signalling, the signal travels and binds the receptor present on the target cell and initiates signalling cascade.
2. The second type involves the release of chemical messenger or signal molecule by signalling cell in the vicinities of the target cell.
3. The third type involves transport of signalling molecule/messenger molecule to target cell through blood.