Question

Communication occurs among the cells in a multicellular organism. For the following scenarios, describe the communication that occurs and the types of responses that result from this communication.
a. Communication between two immune system cells
b. Communication between two plant cells
c. Communication between a neuron and another neuron OR between a neuron and a muscle cell
d. Communication between a specific endocrine gland cell, the hormone that it secretes and its target cell

Answer 1

a. The receptors present on the surface of the immune cells communicate with one another. Their interaction and communication helps in recognizing the self and non-self cells. If the cell is detected as not its own, an immune response is brought in the body. Here the communication is occurring through direct contact with each other cells.

b. Between two plant cells there are connections called plasmodesmata. Through these connections materials are transported from one plant cell to another. The cell wall is rigid and material movement is not easy through cell wall. That is why there are gaps in cell wall which allow easy movement of materials. Large molecules can't pass through the plasmodesmata. Small ions can pass through. Passage of these ions brings certain cellular changes.

c.A neuron communicates with a muscle cell by producing a neurotransmitter which is a chemocal released in the gap present between neuron and muscle. The chemical released will bring certain changes in the muscle cell , resulting in muscle contraction. This is paracrine signalling.

d. The hormones secreted by endocrine glands are released in to the blood. For example, the insulin. When it is released in to blood, insulin will increase the uptake of the glucose in to liver cells where it converts the glucose in to glycogen. Insulin binds to the insulin receptors present on the surface of the liver cells. Binding of the insulin to the receptor will bring certain changes which help in absorbing glucose in to the cells of liver.