Development LP2 - Functions and Childbirth

What is a lobe of the mammary gland?

major glandular unit containing many lobules that produce milk

What are alveoli in the breast

Milk-producing sacs within lobules; stimulated by prolactin.

What is the function of the lactiferous duct

Transports milk from alveoli/lobules toward the nipple

What is the lactiferous sinus?

Expanded region of the duct that stores milk before release.

What is the areola?

Pigmented skin around nipple containing sebaceous glands.

What is the function of the nipple?

Point of milk delivery to the infant; contains openings of milk ducts.

Where does fertilization usually occur?

Ampulla of the uterine (fallopian) tube.

What happens during fertilization?

Sperm enters oocyte → nuclei fuse → zygote forms.

What is implantation?

Blastocyst embeds into the endometrium (uterine lining).

When does implantation occur?

About days 6–7 after fertilization.

What is the pre-embryonic period?

Weeks 1–2: fertilization → cleavage → blastocyst → implantation

What major events occur in the pre-embryonic period?

Rapid cell division, formation of blastocyst, beginning of implantation.

What is the embryonic period?

Weeks 3–6: formation of germ layers + major organ systems (organogenesis).

What major event defines the embryonic period?

Formation of all basic body structures.

What is the fetal period?

Weeks 9–38+: growth, maturation, and functional development of organs.

What happens during the fetal period?

Rapid growth and refinement of organ systems.

What is the amnion?

Membrane that surrounds embryo in amniotic fluid for protection.

What is the chorion?

Forms fetal portion of placenta; important for gas exchange.

What is the yolk sac?

Early nutrient source; forms early blood cells and germ cells.

What is the allantois?

Helps form the umbilical cord and urinary bladder structures.

What does the ectoderm form?

Nervous system, skin, hair, nails.

What does the mesoderm form?

Muscles, bones, blood, heart, kidneys, reproductive organs.

What does the endoderm form?

Digestive tract lining, respiratory lining, liver, pancreas.

What triggers the start of labor?

Increased oxytocin + uterine contractions + positive feedback loop.

What are the three stages of labor?

Dilation → Expulsion → Placental.

What happens in the dilation stage?

Cervix thins and dilates; contractions begin; amniotic sac may rupture

What happens in the expulsion stage?

Baby is delivered through birth canal.

What happens in the placental stage?

Placenta is expelled from uterus.