Complete the sentences with the correct terms. If one plant cell sends a signal to another plant cell by passing a small molecule to that cell through the plasmodesmata, this would be referred to as signaling. After a big meal, in those individuals who do not have Type I diabetes, the pancreas secretes insulin, which circulates through the body and binds to receptors on various cell types to signal to those cells that the body is in the "fed state." This is an example of Neurons secrete neurotransmitters that bind to target cells in the local environment and induce a response. While this is an example of paracrine signaling, it is more specifically referred to as During an allergic response, histamines are released by mast cells. These histamines bind to receptors on cells in the local environment only. This is an example of.

A. direct contact

Also known as juxtacrine signalling where cells in contact are next to each other. Here in this question plasmodesmata which acts as a channel through which molecules move in and out of nearby cells is an example of direct contact signalling.

B. endocrine signalling

In this signalling, signal is sent from one cell to other cells which is far away from the cell. The signal will be in a steady state. Insulin is secreted from Beta cells of pancreas to other target cells through blood. So, insulin secretion is an example for endocrine signalling.

C. synaptic signalling

The junction between nerve cells where transmission of signals is called synapse. And the paracrine signalling that occurs among the neuron cells can be specifically called as synaptic signalling.

D. paracrine signalling

If cells release signals and is passed to the local environment or immediate surrounding areas it is called paracrine signalling. The clue is itself in the question "cells on local environment only". So this histamine signalling to other cells follows paracrine signalling