Which of the following statements about blood vessels is correct?
select one:
a. all blood vessels contain an inner smooth muscle layer.
b. all blood vessels contain a tunica externa.
c. all blood vessels contain a tunica intima.
d. all blood vessels contain an inner connective tissue layer.

b. All blood vessels contain a tunica externa.

Explanation:

Every blood vessel contains a "tunica externa". This is the outer layer of the blood vessel made up of a series of interconnected tissue that provides protection for the blood vessel. There are three types of blood vessels.

All of which have a "tunica externa" but only Arteries and Veins have a "tunica intima". Which is why the answer for this question is B.

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hi there!

answer: b. nucleolus

explanation: nucleolus is a structure in the nucleus are ribosomes are made.

hope this you!

have a nice day! : )

: d

-charlie

you! : )

: d