Q12: Capillaries do not have a tunica media layer. This implies which of the following about capillaries? Capillaries cannot close their valves. Capillaries cannot dilate or contract. Capillaries do not have an outer layer of connective tissue. Capillaries do not contain an inner layer of endothelial tissue.

Capillaries cannot dilate or contract.

Explanation:

The Tunica media layer is mainly responsible for the contractility of blood vessels. Therefore, due to the absence of a tunica media layer in capillaries, these blood vessels are unable to contract or relax.

answer; the above answer to the above statement is (true)

any abiotic or biotic factor in an ecosystem that causes a population's size to slow or decrease is a limiting factor.