Muscles That Guard Entrances and Exits of Internal Passageways Are

question 43

Multiple Choice

Muscles that guard entrances and exits of internal passageways are ________ muscles.

• A) parallel
• B) convergent
• C) pennate
• D) bipennate
• E) circular

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Definitions:

Calcium (Ca)

A soft gray alkaline earth metal, represented by the symbol Ca, essential for living organisms, particularly in cell physiology and bone formation.

Lewis Dot Structure

A diagram that shows the bonding between atoms of a molecule and the lone pairs of electrons that may exist.

Potassium

A soft silvery metal with the symbol K and atomic number 19, essential for life, particularly in nerve function.

Lewis Dot Structure

A visual representation of the valence electrons of an atom, ion or molecule, using dots around symbols of elements.