Chapter 3: Prenatal Development + Birth:

Germinal Period

The period of prenatal development that takes place in the first two weeks after conception.

Blastocyst

A ball of cells formed from the zygote, consisting of an inner group of cells that will become the embryo and an outer group called the trophoblast.

Embryonic Period

The period of prenatal development that occurs two to eight weeks after conception, characterized by cell differentiation and organ formation.

Miscarriage

The expulsion from the uterus of an embryo or fetus that is unable to survive outside the womb.

Fetal Period

The prenatal period of development that begins after two months and lasts for seven months on average, with dramatic growth in size and weight.

Teratogen

Environmental agents, such as a virus or drug, that can interfere with normal prenatal development and cause developmental abnormalities.

Apgar Scale

A scoring system for newborns, assessing five criteria: appearance, pulse, grimace, activity, respiration, with scores ranging from 0 to 2 in each category.

Fetal Viability

The point in fetal development when the fetus can survive outside the womb.

Low Birth Weight

When a baby is born weighing less than 5 pounds, 8 ounces.

First Stage of Birth

The stage during which the cervix is dilating, characterized by uterine contractions.

Second Stage of Birth

The stage that involves the delivery of the infant.

Third Stage of Birth

The stage of delivery that involves the expulsion of the placenta.