PSY Mod 2 Pt 5

Genotype

The total set of genes a person inherits.

Phenotype

The observable or expressed characteristics produced from a person's genetic makeup.

Homozygous

Condition of inheriting the same version of a gene from both parents.

Heterozygous

Condition of inheriting different versions of a gene from each parent.

Dominant gene

A gene that is expressed in the phenotype even when paired with a different version of the gene.

Recessive gene

A gene that is generally expressed only when paired with another identical version.

Polygenic

Describing a characteristic resulting from the influence of multiple genes, such as height, weight, skin tone, or intelligence.

Multifactorial

Describing a trait influenced by multiple factors, including both genetic and environmental influences.

Behavioral genetics

The scientific study of the interaction between genetic and environmental contributions to behavior.

Passive genotype-environment correlation

A situation where parents provide children with both genes and an environment related to those genes.

Evocative genotype-environment correlation

A situation where a person's genetically influenced characteristics evoke particular responses from other people.

Active genotype-environment correlation

A situation where people actively seek environments that fit their genetic tendencies (niche picking).

Epigenetics

The study of how environmental factors influence gene expression without changing the underlying DNA sequence.

Three stages of prenatal development

Germinal, Embryonic, and Fetal.

Germinal stage timeframe

Approximately conception through the first 2 weeks.

Germinal stage processes

Conception, zygote formation, cell division, blastocyst development, and implantation in the uterine wall.

Embryonic stage timeframe

Approximately weeks 3–8.

Embryonic stage primary event

Organogenesis, or the formation of major organs and body structures.

Significance of the embryonic stage

A period of rapid development when the developing organism is especially vulnerable to teratogens and harmful environmental influences.

Fetal stage timeframe

Approximately week 9 through birth.

Fetal stage processes

Rapid growth and continued maturation of organs, the brain, body systems, movement, and reflexes.

Age of viability

Approximately 22–26 weeks, when survival outside the uterus may become possible with intensive medical support.