Chapter 3 Key Terms: Physical Development and Aging

PSY232: Developmental Psychology

adolescent growth spurt

the first outward sign of puberty, refers to a rapid gain in height and weight that generally begins in girls at about age 10 and in boys about age 12

atherosclerosis

condition in which arteries stiffen, and the walls accumulate cholesterol and fat plaques, which reduce blood flow; a cause of heart disease

cephalocaudal development

the principle that growth proceeds from the head downward; the head and upper regions of the body develop before the lower regions

dermis

middle layer of skin consisting of connective tissue that gives skin its flexibility

epidermis

the outer protective layer of the skin that produces new skin cells

free radicals

highly reactive, corrosive substances that form when a cell is exposed to oxygen; through chemical reactions, free radicals destroy DNA, proteins, and other cellular materials

growing pains

intermittent aches and stiffness in the legs often experienced at night that are caused by the stretching and modeling of the muscles to fit the child’s growing skeleton

growth norm

the expectation for typical gains and variations in height and weight for children based on their chronological age and ethnic background

growth stunting

a reduced growth rate

hypodermis

innermost layer of skin composed of fat

inflammation

the process by which the immune system defends the body against irritants, viruses, or injuries

isometric strength

subtle constrictions in which the length of the muscles does not change, is maintained through adulthood

kwashiorkor

a malnutrition disease in children caused by deprivation of protein and calories and characterized by lethargy, bloating and swelling of the stomach

marasmus

a wasting disease in which the body’s fat and muscle are depleted; growth stops and the body wastes away, taking on a hollow appearance

menarche

a girl’s first menstrual period

menopausal hormone therapy (MHT)

physician-prescribed hormones to “replace” declining sex hormones in the body with menopause

menopause

the end of menstruation and a woman’s reproductive capactiy

menstruation

the monthly shedding of the uterine lining, which has thickened in preparation for the implantation of a fertilized egg

nocturnal emissions

involuntary ejaculations that are sometimes accompanied by erotic dreams; also known as wet dreams

ossification

the process of cartilage being converted into bone

osteoporosis

a condition characterized by severe loss of bone mass, leading to increased risk of fractures

perimenopause

transition to menopause in which the production of reproductive hormones declines and symptoms associated with menopause first appear, such as hot flashes

primary sex characteristics

the reproductive organs; in females, this includes the ovaries, fallopian tubes, uterus, and vagina, and in males, this includes the penis, testes, scrotum, seminal vesicles, and prostate gland

proximodistal development

the principle that growth and development proceed from the center of the body outward

puberty

the biological transition to reproductive maturity

sarcopenia

the age-related loss of muscle mass and strength

secondary sex characteristics

physical traits that indicate sexual maturity but are not directly related to fertility, such as breast development and the growth of body hair

secular trend

changes in an aspect of development from one generation to the next

semen

the fluid that contains sperm

senescence

a pattern of gradual age-related declines in physical functioning

spermarche

a boy’s first ejaculation of sperm

telomeres

tiny caps of DNA located at both ends of the chromosomes. Telomeres shorten with each cell division, protecting the DNA but also reducing the cell’s capacity to reproduce, influencing physical aging

testes

the glands that produce sperm