Most of the known single-gene disorders are _____.

Jenny just learned that she is 6 weeks pregnant. She is in the _____ period of prenatal development.

The most common extra-chromosome condition is _____.

A basic nerve cell in the central nervous system is called a(n) “_____.”

Each human has a total of about _____ genes.

The central nervous system includes the ____ and _____.

Any consequence that follows a behavior and makes a person likely to repeat that behavior is called a(n) “_____.

_____ is the thick, high-calorie fluid that is secreted by a new mother’s breasts in the days immediately following birth.

The longest period of prenatal development is the _____ period.

The largest organ in the human body is the liver.