The Layer in the Wall of a Vein That Is

question 8

Multiple Choice

The layer in the wall of a vein that is folded into valves is the:

• A)lining
• B)middle layer
• C)outer layer
• D)smooth muscle layer

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Definitions:

Substance

A form of matter with a specific chemical composition and set of properties that distinguish it from other forms of matter.

Common Isotope

A variant of a chemical element that has the same number of protons but a different number of neutrons in its nucleus, and is normally more abundant than other isotopes.

Carbon

A chemical element with symbol C, essential to all known life forms, and the basis of organic chemistry.

Atomic Mass

The mass of an atom, typically expressed in atomic mass units (amu), representing the total number of protons and neutrons in the nucleus.