The sequence in which the fastest groth occurs at the top of the body--the head--with physical growth in size, weight, and feature differentiation gradually working from top to bottom.
Cephalocaudal pattern
The sequence in which growth starts at the center of the body and moves toward the extremities.
Proximodistal pattern
A period of rapid physical maturation involving hormonal and bodily changes that take place primarily in early adolescence.
Puberty
A girl's first menstruation
Menarche
Very early onset and rapid progression of puberty.
Precocious puberty
Powerful chemical substances secreted by the endocrine glands and carried through the body by the bloodstream.
Hormones
the main class of male sex hormones
Androgens
The main class of female sex hormones
Estrogens
An androgen that is a key hormone in a boys' pubertal development
Testosterone
An estrogen that is a key hormone in girls' pubertal development
Estradiol
Specialization of functions in one hemisphere of the crebral cortex or the other
Lateralization
Brain area where fibers connect the brain's left and right hemispheres.
Corpus callosum
The highest level of the frontal lobes that is involved in reasoning, decision making, and self-control
Prefrontal cortex
The seat of emotions in the brain.
Amygdala
A condition that occurs when an infant stops breathing, usually during the night, and suddenly dies without an apparent cause.
Sudden infant death syndrome
Severe malnutrition caused by an insufficient protein-calorie intake, resulting in a shrunken, elderly appearance.
Marasmus
Severe malnutrition caused by a protein-deficient diet, causing the feet and abdomen to swell with water.