Lesson 26-28

Prenatal development begins at conception, when a sperm fertilizes an egg to form a single cell called a __________.

Zygote

The stage of prenatal development that lasts about two weeks is called the __________ stage.

Germinal

The two types of twins are __________ and __________ twins.

Identical, fraternal

The __________ stage spans from the third to the eighth week of pregnancy, during which major organs begin to form.

Embryonic

The __________ stage focuses on rapid growth, organ refinement, and responsiveness to external stimuli from the ninth week until birth.

Fetal

External factors that can disrupt normal prenatal development are known as __________.

Teratogens

Examples of teratogens include exposure to alcohol, tobacco smoke, certain medications, or __________.

Infections

A mother’s health plays a critical role in prenatal development; infections like __________ can result in congenital disabilities.

Rubella

Genetic mutations can occur __________ or be inherited from a parent.

Spontaneously

Hormonal changes during pregnancy, such as those involving __________ and __________, support healthy fetal development.

hCG, progesterone

____________ refers to a child's primary means of gaining nourishment through sucking.

Sucking

The __________ reflex prompts a baby to turn their head and open their mouth when touched near the cheek.

Rooting

____________ refers to the ability to hold onto objects using the hand and fingers.

Grasping

The __________ reflex, characterized by the fanning out and upward curling of the toes, indicates the immaturity of the nervous system.

Babinski

During the __________ stage, children develop the ability to think logically about concrete events.

Concrete operational

According to Vygotsky's theory, the gap between an individual's current level of development and their potential level with assistance from a skilled individual is called the __________.

Zone of Proximal Development (ZPD)