Answer to Question 1
The sexual response cycle is divided into four phases. The excitement phase is the
body's initial response to sexual stimulation. In females, the vagina becomes
lubricated and in men the penis becomes erect. There are increases in muscle tension, heart rate, and blood pressure. The plateau phase reflects increased arousal. The
penis and vagina continue to enlarge and there is a continued increase in muscle tension, heart rate, and blood pressure. The third phase is orgasm. The pelvic muscles rhythmically contract and there is a sense of intense pleasure. There are other muscular contractions throughout the body. The resolution phase occurs following orgasm. The body returns to its pre-aroused condition. Swollen tissues return to normal and heart rate and blood pressure decrease. Men enter a refractory period in which further orgasm is impossible.
Answer to Question 2
e
The eukaryotic cell cycle
The life cycle of a flowering plant, illustrated by the genus Polygonum
Schematic view of the Calvin cycle
Major regulatory factors controlling pyruvate dehydrogenase and the citric acid cycle
The Let-Down Response
Life cycle of a fern