Menarche, the Onset of Menstruation, Typically Occurs at About ______

question 18

Multiple Choice

Menarche, the onset of menstruation, typically occurs at about ______ years.

• A) 11
• B) 13
• C) 14
• D) 15

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Definitions:

Protons

Positively charged particles within an atom's nucleus.

Neutrons

Neutrons are subatomic particles found in the nucleus of an atom; they are neutral, having no electric charge and a mass slightly greater than that of protons.

Polar Covalent Bonds

A type of chemical bond where a pair of electrons is unequally shared between two atoms, resulting in a molecule with a partially positive end and a partially negative end.

Unequal Sharing

Asymmetric allocation or distribution of resources, responsibilities, or power among parties.