. PRENATAL DEVELOPMENT & EARLY LEARNING

Stages of prenatal development

• Germinal (0–2 weeks): Cell division, implantation.

• Embryonic (3–8 weeks): Major organs form; most sensitive to teratogens.

• Fetal (9 weeks–birth): Growth, brain development, behavior.

Developmental processes

• Cell division: Increases number of cells.

• Cell migration: Cells move to correct location.

• Cell differentiation: Cells specialize.

• Apoptosis: Programmed cell death (e.g., fingers separate).

Fetal support system

• Amniotic sac: Cushions fetus.

• Placenta: Nutrient waste exchange.

• Umbilical cord: Connects fetus to placenta.

Fetal learning

• Fetuses learn smells, sounds, and tastes (e.g., newborns prefer mother’s voice).

Teratogens

• Harmful agents (alcohol, drugs, pollution).

• Most harmful during embryonic stage because organs are forming.

Are fetuses sensitive to sound and light?

Yes.
Evidence: Heart-rate changes to mother’s voice; learning in utero.

Do fetuses learn?

Yes — habituation studies show memory for sounds/tastes after birth.

What affects teratogen impact?

• Dose

• Timing (most severe in weeks 3–8)

• Genetic susceptibility

When are teratogens most dangerous?

Embryonic period (3–8 weeks).

What is apoptosis?

Programmed cell death—crucial for development (e.g., digits).

1. A fetus prefers the mother’s voice after birth because of:
   

2. Alcohol exposure at 4 weeks most likely affects:
   

3. Which support structure provides nutrient exchange?
   

1. B. Prenatal learning

2. A. Organ formation

3. D. Placenta