In Order for Blood to Always Flow Unidirectionally Through a Closed

question 49

Multiple Choice

In order for blood to always flow unidirectionally through a closed circulatory system, the ________.

• A) blood vessels furthest from the heart must have valves
• B) capillaries must have a thick endothelium
• C) arteries must be elastic
• D) pressure in all vessels must be equal

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Definitions:

Ingroup

A social group to which a person psychologically identifies as being a member, often contrasting with an "outgroup" which the person does not identify with.

Outgroup

An outgroup is a social group to which an individual does not identify, often viewed with less favor than the in-group or the group to which the individual belongs.

Ingroup

A group to which an individual belongs, feels a sense of identity, and derives a positive self-esteem from membership.

Outgroup

Any group an individual does not belong to or identify with.