Human Development Ch. 14

Front 1

puberty

Back 1

The time between the first onrush of hormones and full adult physical development. Puberty usually lasts three to five years. Many more years are required to achieve psychosocial maturity.

Front 2

menarche

Back 2

A girl's first menstural period, signaling that she has begun ovulation. Pregnancy is biologically possible, but ovulation and menstration are often irregular for years after menarche.

Front 3

spermarche

Back 3

A boy's first ejaculation of sperm. Erections can occur as early as infancy, but ejaculation signals sperm production. Spermarche may occur during sleep (in a "wet dream") or via direct stimulation.

Front 4

hormone

Back 4

An organic chemical substance that is produced by one body tissue and conveyed via the bloodstream to another to affect some physiological function.

Front 5

pituitary

Back 5

A gland in the brain that responds to a signal from the hypothalamus by producing many hormones, including those that regulate growth and control other glands, among them the adrenal and sex glands.

Front 6

adrenal glands

Back 6

Two glands, located above the kidneys, that produce hormones (including the "stress hormones" epinephrine (adrenaline) and norepinephrine).

Front 7

HPA axis

Back 7

A sequence of hormone production originating in the hypothalamus and moving to the pituitary and then to the adrenal glands.

Front 8

gonads

Back 8

The paired sex glands (ovaries in females, testicles in males). The gonads produce hormones and gametes.

Front 9

HPG axis

Back 9

A sequence of hormone production originating in the hypothalamus and moving to the pituitary and then to the gonads.

Front 10

estradiol

Back 10

A sex hormone, considered the chief estrogen. Females produce much more estradiol than males do.

Front 11

testosterone

Back 11

A sex hormone, the best known of the androgens (male hormones); secreted in far greater amounts by males than by females.

Front 12

leptin

Back 12

A hormone that affects appetite and is believed to affect the onset of puberty. Leptin levels increase during childhood and peak at around age 12.

Front 13

secular trend

Back 13

A long-term upward or downward direction of a certain set of statistical measurements, as opposed to a smaller, shorter cyclical variation. As an example, over the last two centuries, because of improved nutrition and medical care, children have tended to reach their adult height earlier and their adult height has increased.

Front 14

body image

Back 14

A person's idea of how his or her body looks.

Front 15

anorexia nervosa

Back 15

An eating disorder characterized by self-starvation. Affected individuals voluntarily undereat and often overexercise, depriving their vital organs of nutrition. Anorexia can be fatal.

Front 16

bulimia nervosa

Back 16

An eating disorder characterized by binge eating and subsequent purging, usually by induced vomiting and/or use of laxatives.

Front 17

growth spurt

Back 17

The relatively sudden and rapid physical growth that occurs during puberty. Each body part increases in size on a schedule. Weight usually precedes height, and growth of the limbs precedes growth of the torso.

Front 18

primary sex characteristics

Back 18

The parts of the body that are directly involved in reproduction, including the vagina, uterus, ovaries, testicles, and penis.

Front 19

secondary sex characteristics

Back 19

Physical traits that are not directly involved in reproduction but that indicate sexual maturity, such as a man's beard and a woman's breasts.

Front 20

sexually transmitted infection (STI)

Back 20

A disease spread by sexual contact, including syphilis, gonorrhea, genital herpes, chlamydia, and HIV.

Front 21

child sexual abuse

Back 21

Any erotic activity that arouses an adult and excites, shames, or confuses a child, whether or not the victim protests and whether or not genital contact is involved.