1) Puberty involves biological and physical changes that transform children into adults, driven by genetic and hormonal factors. 2) Hormones secreted by the hypothalamus, pituitary gland, and gonads stimulate maturation and development of sex organs during puberty. 3) While the process of physiological changes in puberty is consistent, the timing and rate of changes varies between individuals. Puberty generally begins earlier in girls than boys.

1. CHAPTER 2
PUBERTY, HEALTH AND BIOLOGICAL FOUNDATIONS
______________ and ______________ changes are the essence of adolescent development. They
encompass a sequence of events that transforms a ______________ into an ______________ . The
predictable ______________ metamorphosis offers little opportunity for deviation. ______________
is defined as a period of ______________ physical ______________ predominantly occurring during
______________ adolescence because of genetic predisposition (______________ )
Genetic inheritance dictates the need for the body to achieve specific functional ______________ ,
and influences ______________ curves by following ______________ pattern: 1) Maturity gradients
—the ______________ and ______________ must be ______________ developmental step ahead of
other ______________ (i.e., neural tube, myelin sheath, nerve endings) to provide the
______________ for the development of other body ______________ ; 2) Feedback regulation—the
lymphatic system regulates ______________ secretions to make the ______________ structure
functional. ______________ produced by ______________ are secreted directly into the
______________ and are circulated to influence cell growth; 3) Body mass—the ______________
structure influences the onset of ______________ spurts or ______________ (i.e., marked
______________ gains coincide with ______________ onset), health expectations identified by
______________ and ______________ gains are required before 4) the ______________ growth
spurt begins.
Hormones—reproductive systems become functional as ______________ and ______________
secreted by the ______________ glands and carried by the bloodstream influence the development of
sex organs;
The endocrine system through interaction between the hypothalamus, the pituitary gland, and gonads,
ensures that hormonal stimulation prompts maturation and maintains reproductive capacity through a
negative feedback system; the hypothalamus produces chemicals known as releasing factors, which
the blood stream carries to the pituitary gland stimulating it to produce substances called
gonadotropins, which stimulates the gonads. In late middle childhood, concentrations of these
gonadotropins, which include follicle-stimulating hormones and luteinizing hormone, begin to
increase. In turn these hormones induce the ovaries to produce female sex hormones and the testes to
produce sperm in males and mature ova in females. The sex hormones produce by the gonads cause
the pubertal changes in the body.
The physical changes that occur during puberty affect every area of development. The
______________ of physiological changes in puberty is ______________ , but the ______________
of the changes ______________ from ______________ to ______________ . For example, the
______________ of ______________ maturation is consistent across adolescents, but the
______________ and time of ______________ is highly individual.
Both sexes experience a ______________ spurt in ______________ and ______________ before
______________ maturation begins. Girls, as a group, ______________ and begin puberty a
______________ of years earlier than boys. The growth spurt in males does not occur until a
______________ of other ______________ changes have taken place, for example the full
development of the ______________ . ______________ boys and girls are very similar

2. ______________ , but puberty produces marked ______________ in a relatively ______________
period of ______________ , due largely to dramatic changes in ______________ balance between
______________ and ______________ .
When physical growth ______________ considerably, it signals the onset of ______________ , or
______________ . ______________ follows the peak velocity in height increase, so it has been
attributed to critical body mass, percentage of body fat that signal readiness for puberty.
The ______________ trend for the age at which ______________ begins has gradually
______________ during the twentieth century, but ______________ limits will prevail. Since 1900,
children each ______________ have been growing ______________ at the rate of approximately
______________ centimeter and ______________ by half a ______________ . Between
______________ and ______________ , the age of ______________ averaged some
______________ or ______________ months earlier each ______________ , although the
______________ was greater in some decades compared to others. This trend is found across all
______________ nations. ______________ trend is likely due to an ______________ in
______________ , a decline in ______________ -retarding illnesses during the first 5 years of life and
better ______________ care.
Psychological changes that accompany adolescence include perceptions by ______________ ,
______________ , and ______________ themselves. Adolescents become preoccupied with changes
in ______________ image, with ______________ showing less ______________ than
______________ . Hormonal changes have an effect on adolescent ______________ , but
______________ factors are ______________ to ______________ times more influential than
hormones. For example, adolescent ______________ report only mild ______________ responses to
______________ , especially if they are ______________ for the experience.
______________ maturation has particularly ______________ effects on ______________ and
______________ . ______________ maturing ______________ are more ______________ and begin
______________ earlier. ______________ maturing ______________ are considered more
______________ and ______________ , as well as more ______________ and self-
______________ . Meanwhile, ______________ maturation in ______________ is also associated
with increase likelihood of ______________ in ______________ and lower ______________ , and a
less ______________ body ______________ . In ______________ , ______________ maturation is
associated with ______________ problems in ______________ .
______________ maturation provides opportunity for ______________ , and leads to greater
______________ with ______________ image for ______________ - rather than ______________
-maturing ______________ . ______________ maturing boys are more ______________ ,
______________ and ______________ as adults. ______________ maturing girls are less
______________ to ______________ pressure, especially pressure to engage in ______________
conduct. ______________ maturing boys are considered ______________ , more ______________
and more ______________ seeking. Social context influences the complexity in interpreting
outcomes of on-time and off-time pubertal events. For example, parents perceive less
______________ with ______________ maturing ______________ . In contrast, ______________

3. maturing ______________ are perceived to be a source of more ______________ and
______________ for their parents.
Adolescence is a ______________ juncture in ______________ . On one hand adolescents reach a
level of ______________ , ______________ and ______________ that they will never
______________ during the rest of their lives. And on the other hand many behaviors linked to
______________ habits and early ______________ in adults ______________ during adolescence.
Health ______________ developed in ______________ seem to carry ______________ through
______________ . Adolescence is a ______________ junction in the ______________ of
______________ -related behaviors.
Adolescents’ peak ______________ condition and feelings of ______________ may lead to the
development of ______________ health habits. Experts are interested in decreasing health-
______________ behaviors and increasing health-______________ behaviors. The ______________
behavior that we want to ______________ through regular practice includes weight ______________ and
physical ______________ . The ______________ behavior that we want to ______________ or
______________ includes eating ______________ high in ______________ and ______________ ,
______________ , drinking too much ______________ , and eating too ______________ or too
______________ for our ______________ needs.
Adolescents get too little ______________ and are perpetually ______________ . Adolescents also are
prone to changes in the circadian timing (______________ ) during ______________ , resulting in the
tendency to have ______________ onset of ______________ and difficulty ______________ .
Adolescents need ______________ hours of sleep a ______________ . They also tend to want to stay up
______________ and get up ______________ in the morning. Because of ______________ start times,
adolescents experience a sleep ______________ . Sleep is a necessity for success in school. . Poor sleep
habits by adolescents are associated with poor self-reported school ______________ ; increased
______________ of ______________ sleepiness; greater use of ______________ , ______________ , and
______________ ; evening phase delay preference; and ______________ and ______________ mood.
Most adolescents appear to not seek ______________ for their sleep difficulties, but are prone to use
______________ to help themselves sleep.
Common elements of the human genome make it possible for our species to thrive. For example, the
genotype contains all of the genetic material inherited from both parents; the phenotype reflects
observed characteristics, far less than the genetic code transmits; Behavior genetics investigates the
influence of nature and nurture on behavior.
A ______________ study investigates the similarity between identical and fraternal twins. An
______________ study investigates ______________ of children and ______________ versus
______________ parents. Research designs using ______________ and ______________ twins,
raised by ______________ or ______________ parents, help to determine the influence of
______________ characteristics and ______________ influence. Observable patterns are: 1) Passive
genotype-environment correlations—environments that reflect ______________ preferences; for
example, ______________ ability is in some measure affected by ______________ factors, and
parents both ______________ on ______________ for this ability and create an ______________ in
which this ______________ can be ______________ . The importance of passive effects

4. ______________ as children, especially ______________ gain more ______________ and have more
opportunities to choose their own ______________ ; 2) Evocative genotype-environment correlations
—the child’s inherited ______________ preferences; for example ______________ and
______________ adolescents receive different ______________ from others than do
______________ adolescents. ______________ teens receive different ______________ than
______________ teens. The importance of evocative effects ______________ throughout
______________ 3) Active (niche-picking) genotype-environment correlations—preferred
environments identified by the child and in which the child chooses to participate; 4) Shared
environmental influences—shared ______________ within the ______________ ; such as their
parent’s ______________ , social ______________ and ______________ ; 5) Non-shared
environmental influences—______________ experiences influencing ______________ variation;
both within a ______________ and outside the ______________ , that are not shared by a
______________ .
In summary, genetics and environment are mutually instrumental; one cannot be without the other.