The heart begins to beat during the ________ period of prenatal development.

A) embryonic
B) fetal
C) zygotic
D) ovular

Heart

An organ in most animals that pumps blood through the circulatory system to supply oxygen and nutrients to the body.

Embryonic Period

A critical phase in early development after conception where major organs and structures within the embryo begin to form.

Beat

A rhythmic unit in music and poetry, or the sound made by a clock or other rhythmic device.