Which of the following statements about focal adhesions is true?
a. they anchor cells to the substratum.
b. they can be rapidly disassembled upon a changing environment.
c. they may act as a type of sensory structure leading to cell growth.
d. all of these answers are correct.

d.All of these answers are correct

Explanation:

What are focal adhesions?

Focal adhesions have multi protein structure which forms links between intracellular and extracellular matrix in cells.

They form on moving cells and they grow and mature as the cells keep moving they act as holding points when the cells are moving from one site to another to promote protrusion but supress membrane contractions. In those cells which do not move they act as anchors to keep fell morphology.

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