Human Development Chapter 2 Study Guide Flashcards

Vocabulary flashcards covering core genetic foundations, inheritance patterns, environmental influences, and gene-environment interactions from Chapter 2.

Genotype

An individual's unique genetic information.

Phenotype

An individual's directly observable characteristics.

Chromosomes

Structures that store and transmit genetic information.

DNA

The substance of which genes and chromosomes are made.

Gene

A segment of DNA located along a chromosome.

Meiosis

The process that creates gametes (sex cells), halves the chromosome number, and promotes genetic variability.

Gametes

Sex cells, specifically sperm and ovum.

Zygote

The cell formed when sperm and ovum unite, containing $46$ chromosomes.

Autosomes

The $22$ matching pairs of chromosomes in humans.

Sex Chromosomes

The $23\text{rd}$ pair of chromosomes (XX = female; XY = male in lecture terminology) that determines sex.

Fraternal (Dizygotic) Twins

Twins resulting from two separate zygotes (two fertilized ova).

Identical (Monozygotic) Twins

Twins resulting from one zygote dividing into two individuals.

Alleles

Two forms of the same gene, one inherited from each parent.

Homozygous

Having two identical alleles at a given locus (e.g., AA or aa).

Heterozygous

Having two different alleles at a given locus (e.g., Aa).

Dominant Allele

An allele that affects the child's characteristics when present.

Recessive Allele

An allele that can be passed to children without being expressed in a carrier.

Genomic Imprinting

A process where a chemical marker activates one allele in a pair; it is often temporary and may not pass to the next generation.

Mutation

A sudden, permanent change in a DNA segment, which may occur spontaneously or from hazardous environmental agents.

Polygenic Inheritance

A pattern of inheritance in which many genes affect a single characteristic, such as height, weight, intelligence, and personality.

Down Syndrome

A chromosomal disorder that results when the $21\text{st}$ chromosome pair fails to separate during meiosis.

Genetic Counseling

A clinical service that helps couples assess hereditary-disorder risk and choose an appropriate course of action.

Socioeconomic Status (SES)

A measure combining three related variables: years of education, occupational prestige/skill, and income.

Collectivism

A cultural context that stresses group goals, interdependence, responsibility to others, social harmony, and collaboration.

Individualism

A cultural context that emphasizes personal needs, independence, achievement, exploration, and choice.

Behavioral Genetics

A field of study that explores the contributions of nature and nurture to differences in human traits and abilities.

Heritability Estimates

Measures ranging from $0$ to $1.00$ that estimate the extent to which individual differences in complex traits in a group are due to heredity.

Gene-Environment Interaction

The principle that individuals can respond differently to the same environment because of differences in their genetic makeup.

Gene-Environment Correlation

The concept that an individual's genes influence the environments to which they are exposed.

Passive Correlation

A type of gene-environment correlation in which the environment is provided to the child by the parents.

Evocative Correlation

A type of gene-environment correlation in which a child's genetically influenced characteristics evoke reactions from others.

Active Correlation (Niche-Picking)

A type of gene-environment correlation in which individuals actively select environments that fit their genetic tendencies.

Epigenesis

Ongoing, bidirectional exchanges where genes affect behavior and experiences, while behavior and experiences affect gene expression.

Epigenetics

The study of how the environment alters gene expression, with methylation given as a primary example.