Physical Development

Stages of Development

1. Germinal Stage

   1. Time Period: 0-2 weeks

   2. Zygote turns into a blastocyst

   Major Developments:

   1. Rapid cell division (at this point, the cells are duplicating but not yet tied to a specific function

2. Embryonic Stage

   1. Time Periods: 3-8 weeks

   2. Embryo

   Major Development: Greatest period of vulnerability

   1. Limbs, facial features, sexual differentiation

   2. Heart beats at 9th week

3. Fetal Stage

   1. Time Period: 9th week birth (40 weeks)

   2. Fetus starts to move on its own

   Major Development:

   1. Rapid growth of body and brain

   2. Movement capability

   3. Viability point: Can survive if birthed at this time (25 weeks)

      1. Premature infants are born less than 36 weeks

Environmental Hazards

1. Teratogens: Environmental factors that have. anegative impact on prenatal development

   1. Mental health, diet, substances

2. Fetal Alcohol Spectrum Disorder: Physical changes, malformations, and cognitive changes due to alcohol consumption

   • The impact on prenatal development depend on when the mother consumed alcohol and at what point

Prenatal Development: ****

The Brain

The brain starts to develop 18 days after fertilization

Proliferation Growth of tissue cells

• Begins day 18 - 6 months

Migration: Cells from original place to another which starts in 4th month

Motor Development

Reflexes: Exists in the first 6 months at births. Doctors test if these reflexes are present to find damage to neural development

1. Sucking Reflex:

2. Rooting Reflex

3. Grasping Reflex

4. Moro Reflex (falling)

5. Babinski Reflex (stroking foot)

Motor Behaviours: Bodily motions that occur as result of self-initated force that moves the bones and muscles

Factoes influencing motoro development:

1. Weight of infant

   1. If baby is heavier it has more muscle to support its weight

2. Experience and exploration

   1. Have to experience different distances and slops

3. Cultural Practices