Genetics, Prenatal Development, and Early Childhood Psychology

[Genetics & Prenatal Development] What does the nucleus of a cell contain?

The nucleus contains chromosomes made of DNA, which carry genes that determine inherited traits.

[Genetics & Prenatal Development] What is the difference between genotype and phenotype?

Genotype is a person's genetic makeup, while phenotype is the observable physical and behavioral expression of those genes.

[Genetics & Prenatal Development] What is meiosis and why is it important?

Meiosis is the cell division process that creates gametes (sperm and ova), halving the number of chromosomes to ensure genetic variability when gametes unite.

[Genetics & Prenatal Development] Distinguish between monozygotic and dizygotic twins.

Monozygotic (identical) twins come from a single zygote that splits, sharing 100% of genes. Dizygotic (fraternal) twins come from two separate eggs and share about 50% of genes.

[Genetics & Prenatal Development] What are the three stages of prenatal development?

1) Germinal (0-2 weeks): Fertilization to implantation. 2) Embryonic (3-8 weeks): Organ and structure formation. 3) Fetal (9 weeks-birth): Growth and brain refinement.

[Genetics & Prenatal Development] What are teratogens and when are they most dangerous?

Teratogens are environmental agents like drugs, alcohol, or infections that cause prenatal damage. They are most dangerous during the embryonic period (weeks 3-8).

[Genetics & Prenatal Development] How do maternal nutrition and stress affect prenatal development?

Poor nutrition (e.g., lack of folic acid) can cause neural defects. Chronic stress increases cortisol, restricting oxygen and nutrients to the fetus, leading to low birth weight.

[Genetics & Prenatal Development] What is the difference between preterm and small-for-date infants?

Preterm babies are born before 37 weeks with immature organs, while small-for-date babies are full-term but weigh less than expected due to growth restriction.

[Physical Development] What are the cephalocaudal and proximodistal trends?

Cephalocaudal: growth from head to tail. Proximodistal: growth from the body's center outward toward the limbs.

[Physical Development] What happens to the brain during infancy?

Rapid neural growth occurs; synapses form, then unused ones are pruned. Myelination speeds up neural transmission, improving coordination and learning.

[Physical Development] Why are sensitive periods important in brain development?

They are windows when the brain is especially receptive to learning certain skills (e.g., language). Lack of stimulation can cause lasting deficits.

[Physical Development] What are the main influences on early physical growth?

Heredity, nutrition (especially breastfeeding), and emotional well-being all affect physical development.

[Physical Development] How does the dynamic systems theory explain motor development?

Motor skills develop from interaction between the child's nervous system, body capacities, goals, and environmental support.

[Physical Development] What are typical motor milestones in the first two years?

Grasp cube (~3 mo), sit alone (~7 mo), crawl (~7 mo), walk (~12 mo), jump (~23 mo).

[Cognitive Development] What is Piaget's sensorimotor stage?

Birth to 2 years: infants learn through senses and movement, gradually developing object permanence and intentional behavior.

[Cognitive Development] Define object permanence and when it appears.

Understanding that objects exist even when out of sight; begins around 8-12 months and strengthens into the second year.

[Cognitive Development] What is deferred imitation?

The ability to remember and copy a model's behavior later, showing memory and representational ability.

[Cognitive Development] How does the information-processing model explain thinking?

It views the mind like a computer: information flows through sensory register, working memory, and long-term memory, directed by a central executive.

[Cognitive Development] What is Vygotsky's zone of proximal development?

The range of tasks a child can't do alone but can achieve with help from a skilled partner through scaffolding.

[Cognitive Development] What are major early language milestones?

Cooing (2 mo), babbling (6 mo), first words (~1 yr), vocabulary spurt and two-word combinations (~2 yrs).

[Emotional & Social Development] What are Erikson's first two psychosocial stages?

1) Trust vs. Mistrust (0-1 yr): Responsive caregiving → security. 2) Autonomy vs. Shame/Doubt (1-3 yrs): Guidance and reasonable choices → independence.

[Emotional & Social Development] When do basic and self-conscious emotions emerge?

Basic emotions (happiness, anger, fear) appear by 6 months; self-conscious emotions (shame, guilt, pride) around 18-24 months.

[Emotional & Social Development] What is emotion regulation and how does it develop?

It's the ability to manage emotions; develops rapidly with brain maturation and caregiver support during the first two years.

[Emotional & Social Development] What is social referencing?

At 8-10 months, infants use caregivers' emotional cues to interpret unfamiliar situations and guide actions.

[Emotional & Social Development] Describe Ainsworth's attachment classifications.

Secure (60%), Avoidant (15%), Resistant (10%), Disorganized (15%)—based on the infant's reaction to caregiver separation and reunion.

[Emotional & Social Development] What factors affect attachment security?

Quality of caregiving, parental responsiveness, family stress, infant temperament, and parents' attachment history.

[Emotional & Social Development] What is temperament, and what are the main types?

Temperament is early-appearing individual differences in reactivity and self-regulation: Easy, Difficult, Slow-to-warm-up, or Unclassified.

[Culture, Environment, and Research] Explain the goodness-of-fit model.

Effective parenting adapts to a child's temperament, encouraging adaptive behavior and emotional security.

[Culture, Environment, and Research] How do cultures differ in promoting independence vs. interdependence?

Individualistic cultures (e.g., U.S.) emphasize autonomy; collectivist cultures (e.g., Japan) promote family and group harmony.

[Culture, Environment, and Research] What does Bronfenbrenner's ecological systems theory explain?

Development occurs within multiple environmental systems: microsystem (family), mesosystem, exosystem, macrosystem, and chronosystem.

[Culture, Environment, and Research] What are the main research methods in developmental science?

Observations, self-reports, case studies, correlational and experimental designs; each has strengths and limitations.

[Culture, Environment, and Research] What are longitudinal and cross-sectional designs?

Longitudinal: track same people over time. Cross-sectional: compare different age groups at one time.

[Culture, Environment, and Research] What does 'nature vs. nurture' refer to?

The debate over whether development is shaped more by genetics (nature) or environment (nurture)—now understood as interactive.