Question

Communication junctions
(intercalated discs) at some fusion points allow the cells to contract as a
unit, i.e., when one cell receives a signal to contract, its neighbours are
also stimulated to contract. plz explain this line​

Answer 1

Answer:

Intercalated discs are cellular junctions.

It's major function is to transfer electrical impulses extremely fast and hence the all the neighbouring cells to contract approximately at the same time.

Intercalated discs contain 2 components

a) Gap junctions : responsible for rapid transfer of ions from one cell to another.

b) Desmosome: hold the neighbouring cells together and prevent their separation during separation.

These intercalated discs are present in the heart muscles.

So when one cell receives electric stimulus, the stimulus is transferred to the nearby cells instantly and the neighbouring cells also contract immediately.

Answer 2

Answer:

$Intercalated discs are microscopic structures of cardiac muscle. They occur at the Z-line of the sarcomere and are made of fascia adherens, desmosomes and gap junctions. They are cross bands that separate the opposite ends of myocytes. These discs hold the adjacent cells together and allow diffusion of ions across the cells due to which muscle impulses travel rapidly from cell to cell leading to their contraction. Thus the correct answer is option D.$