Biological Transitions Flashcards
(31 cards)
What are the four chief physical manifestations of puberty?
- A rapid acceleration in growth, resulting in dramatic increases in height and weight.
- The development of primary sex characteristics which results in a series of hormone changes
- The development of secondary sex characteristics
- Changes in the brain’s anatomy and activity as a result of hormonal influences.
What is the endocrine system?
The system of the body that produces, circulates, and regulates hormones
What are hormones?
Highly specialized substances secreted by one or more endocrine glands
What are glands?
Organs that stimulate particular parts of the body to respond in specific ways to particular hormones
What are gonadotropin-releasing hormone (GnRH) neurons?
Specialized neurons that are activated by certain pubertal hormones
What is a set point?
A physiological level or setting (e.g. of a specific hormone) that the body attempts to maintain through a well-regulated system
What is a feedback loop?
A cycle through which two or more bodily functions respond to and regulate each other, such as that formed by the hypothalamus, the pituitary gland, and the gonads (HPG axis)
What is the pituitary gland?
One of the chief glands responsible for regulating levels of hormones in the body
What is the hypothalamus?
A part of the brain that controls the functioning of the pituitary gland
What are gonads?
The glands that secrete sex hormones: in males, the testes; in females, the ovaries
What are androgens?
A class of sex hormones secreted by the gonads, found in both sexes but in higher levels among males than females following puberty
What are estrogens?
A class of sex hormones secreted by the gonads, found in both sexes but in higher levels among females than males following puberty
What is andrenarche?
The maturation of the adrenal glands that takes place during adolescence
What is cortisol?
A hormone produced when a person is exposed to stress
What is kisspeptin?
A brain chemical believed to trigger the onset of puberty
What is melatonin?
A hormone secreted by the brain that contributes to sleepiness and that triggers the onset of puberty through its impact on kisspeptin.W
What is leptin?
A protein produced by fat cells that may play a role in the onset of puberty through its impact on kisspeptin
What is the adolescent growth spurt?
The dramatic increase in height and weight that occurs during puberty
What is epiphysis?
The closing of the ends of the bones which terminates growth after the adolescent growth spurt has been completed
What are secondary sex characteristics?
The manifestation of sexual maturity at puberty, including the development of breasts, the growth of facial and body hair, and changes in the voice
What are Tanner stages?
A widely used system that describes the five stages of pubertal development
What is menarche?
The time of first menstruation, one of the most important changes to occur among females during puberty
What are pheromones?
A class of chemicals secreted by animals that stimulate certain behaviors in other members of the species
What is the secular trend?
The tendency, over the past two centuries, for individuals to be larger in stature and to reach puberty earlier, primarily because of improvements in health and nutrition
