Hormonal increases directly lead to interest in sex.

True

Janice is experiencing precocious puberty. This means that she is experiencing sexual development before the age of 6.

False

Body chemicals that regulate sleep, moods, hunger, and stress are called "_____."

hormones

In the twenty-first century, early puberty positively correlates with _____.

aggression and antisocial behavior in boys

What substance(s) cause(s) the ovaries and testes to greatly increase their production of estradiol and testosterone?

gonadotropin-releasing hormone

For boys, the first ejaculation of seminal fluid is _____.

spermarche

Christine, who is going on 12 years of age, has just experienced a sudden growth spurt. She is likely to next notice _____.

her hips growing wider

About _____ of the variation in age of puberty is determined by genes.

two-thirds

For boys, the first ejaculation generally occurs _____.

following growth of the penis

The day-night cycle that occurs approximately every 24 hours is the _____.

circadian rhythm

National differences in the timing of menarche are due to:

genetic and nutritional reasons.

_____ are the sex hormones secreted in greater amounts by males than females.

androgens

Which of the following symptoms is NOT associated with anorexia nervosa?

average weight

One of the first signs of the growth spurt is _____.

growth of fingers and toes

One physical change that typically occurs during adolescence is that the _____.

heart doubles in size

The recommended daily dose of calcium is _____ milligrams; most teens consume less than _____ milligrams per day.

1,300; 500

During the adolescent growth spurt, what is/are the last part(s) of the body to grow?

torso

Data indicates a marked decline in _____ rates in most countries for the past few decades.

teen birth

Primary sex characteristics include pubic hair and nipple changes.

False

_____ is the most frequently reported STI.

Chlamydia