branch of psychology that studies physical, cognitive, and social change throughout the life span.
threadlike structures made of DNA molecules that contain the genes.
DNA (deoxyribonucleic acid)
molecule containing the genetic information that makes up the chromosomes
the biochemical units of heredity that make up the chromosomes; a segment of DNA.
the genetic transfer of characteristics from parents to offspring.
the complete instructions for making an organism, consisting of all the genetic material in that organism's chromosomes.
every external influence, from prenatal nutrition to social support in later life
the interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity)
the fertilized egg; it enters a 2-week period of rapid cell division and develops into an embryo.
the developing human organism from about 2 weeks after fertilization through the second month
twins who develop from a single fertilized egg that splits in two, creating two genetically identical siblings
twins who develop from separate fertilized eggs. They are genetically no closer than nontwin brothers and sisters, but they share a prenatal environment.
the developing human organism from 9 weeks after conception to birth
an agent, such as a chemical or virus, that can reach the embryo or fetus during prenatal development and cause harm
fetal alcohol syndrome (FAS)
physical and cognitive abnormalities in children caused by a pregnant woman's heavy drinking. In severe cases, symptoms include noticeable facial misproportions
an unlearned, automatic response to a sensory stimulus
a person's characteristic emotional reactivity and intensity
biological growth processes leading to orderly changes in behavior, independent of experience
a period early in life when exposure to certain stimuli or experiences is needed for proper development
a concept or framework that organizes and interprets information
all the mental activities associated with thinking, knowing, remembering, and communicating
in Piaget's theory, the stage (from birth to about 2 years of age) during which infants know the world mostly in terms of their sensory impressions and motor activities
the awareness that things continue to exist even when not perceived.
in Piaget's theory, the stage (from about 2 to 6 or 7 years of age) in which a child learns to use language but cannot yet perform the mental operations of concrete logic
the principle (which Piaget believed to be a part of concrete operational reasoning) that properties such as mass, volume, and number remain the same despite changes in shapes
in Piaget's theory, the preoperational child's difficulty taking another's point of view
theory of mind
people's ideas about their own and others' mental states—about their feelings, perceptions, and thoughts, and the behaviors these might predict
a disorder that appears in childhood and is marked by deficient communication, social interaction, and understanding of others' state of mind.
concrete operational stage
in Piaget's theory, the stage of cognitive development (from about 6 or 7 to 11 years of age) during which children gain the mental operations that enable them to think logically about concrete events
formal operational stage
in Piaget's theory, the stage of cognitive development (normally beginning about age 12) during which people begin to think logically about abstract concepts.
the fear of strangers that infants commonly display, beginning by about 8 months of age.
an emotional tie with another person; shown in young children by their seeking closeness to the caregiver, and showing distress on separation
according to Erik Erikson, a sense that the world is predictable and trustworthy; said to be formed during infancy by appropriate experiences with responsive caregivers.
the transition period from childhood to adulthood, extending from puberty to independence
the period of sexual maturation, during which a person becomes capable of reproducing
the first menstrual period
our sense of self; according to Erikson, the adolescent's task is to solidify a sense of self by testing and integrating various roles.
the "we" aspect of our self-concept; the part of our answer to "Who am I?" that comes from our group memberships
in Erikson's theory, the ability to form close, loving relationships; a primary developmental task in early adulthood
a period from about age 18 to the mid-twenties, when many in Western cultures are no longer adolescents but have not yet achieved full independence as adults
the end of menstruation. In everyday use, it can also mean the biological transition a woman experiences from before to after the end of menstruation
accumulated knowledge and verbal skills; tends to increase with age
ability to reason speedily and abstractly; tends to decrease during late adulthood.
the culturally preferred timing of social events such as marriage, parenthood, and retirement