PSY - Development

Developmental psychology is the

The study of how people change physically, mentally, and socially over the lifespan.


A single cell formed at conception from the union of the egg cell and the sperm cell that contains the unique set of genetic instructions inherited from our biological parents.


Long threadlike structures composed of twisted parallel strands of DNA; found in the cell nucleus.

DNA (deoxyribonucleic acid)

The double stranded molecule that is the chemical basis of heredity and carries genetic instructions in the cell.


Basic units of heredity and consist of segments of DNA strung like beads along the chromosomes.

Genes direct the manufacture of



The genetic makeup of an individual organism


One of the different forms of a particular gene.

The human genome

Scientific description of the complete set of DNA in the human organism, including gene locations.

The best-known pattern of allele variation is

Dominant -recessive gene pair.

Phenotype refers to the

Observable traits or characteristics of an organisms as determined by the interaction of genetics and environmental factors.

Rather than being fixed or inevitable, gene expression is


Genetic Predispositions

Particular genetic configurations that are more or less sensitive to specific environmental factors and so influence in certain ways.

During prenatal development, the single-cell zygote

Undergoes rapid cell division before becoming impanted on the wall of the mom�s uterus. Eventually, it develops into a full-term fetus.

The 3 phases of prenatal stages are

Germinal Stage (1-2 weeks) - rapid cell division. Embryonic stage (3-8 weeks) � massive cell differentiation, major organs form. Fetal stage (9 weeks � birth) � by 5th week all brain cells present, 6th month age of viability.


Harmful agents or substances that can cause malformations or defects in an embryo or fetus.

Newborn infants enter the world equipped with

The rooting reflex, the sucking reflex, and the grasping reflex. Their senses of vision, hearing, smell, and touch are keenly attuned to people and this ability helps them differentiate between their mothers and other people.