Any repeating cycle of biological activity, such as sleep and waking cycles or changes in body temperature, is known as a(n)

Preschoolers have a tendency to try to make up a reason why things that they see and hear occur. This tendency is known as

reversibility. focus on appearances. theory-theory. logical reasoning.

Twins produced when a cluster of cells splits off of one ovum within 2 weeks after fertilization are called ___________ twins

a. dizygotic c. dominant b. monozygotic d. recessive