Pregnancy And Childbirth

Front 1

Homologous Chromosomes

Back 1

a pair of similar autosomes

Front 2

Haploid Cells

Back 2

23 single chromosomes

Front 3

Diploid Cells

Back 3

23 pairs of chromosomes (46 total)

Front 4

Meiosis

Back 4

Cell division that produces haploid daughter cells from a diploid parent cell

Front 5

Down Syndrome

Back 5

1) Trisomy 21
2) Results from Nondisjunction
3) Incidence increases with mother's age

Front 6

Review of Oogenesis

Back 6

1) Primary oocytes of a female are arrested in Prophase I until puberty
2) One primary oocyte a month divides into a secondary oocyte and polar body
3) Oocyte is ovulated
4) If not fertilized in 24 hours oocyte degenerates
5) If fertilized, it finishes meiosis and produces an ovum and polar body

Front 7

Fertilization

Back 7

1) Restores the diploid number of cells
2) Occurs in the ampulla
3) Capacitation

Front 8

Capacitation

Back 8

1) Conditioning when sperm coat is modified to be able to fertilize the oocyte
2) Glycoprotein coat and proteins are removed from sperm plasma membrane over the acrosome

Front 9

Three Phases of Fertilization

Back 9

1) Corona Radiata Penetration
2) Zona Pellucida Penetration
3) Fusion of Sperm and Oocyte Plasma Membrane

Front 10

Corona Radiata Penetration

Back 10

Acrosome Reaction: release enzymes from acrosome; forms passageway between cells

Front 11

Zona Pellucida Penetration

Back 11

1) Other sperm able to release enzymes to penetrate zona
2) Once one sperm penetrates zona, it hardens and prevents polyspermy

Front 12

Fusion of Sperm and Oocyte Plasma Membrane

Back 12

1) Once the nucleus of the sperm enters the secondary oocyte, the oocyte completes second meiotic division
2) The pronuclei of the sperm and ovum fuse, formin a single nucleus

Front 13

Implantation

Back 13

1) Zona Pellucida begins to break down
2) Trophoblast cells invade the endometrium
3) Cytotrophoblast subdivides
A) Cytotrophoblast(inner layer)
B) Syncytiotrophoblast (outer layer)- burrows into the endometrium

Front 14

Tubal Pregnancy

Back 14

1) Ectopic pregnancy
2) Fertilized oocyte implants in the uterine tube
3) Uterine tube unable to expand as fetus develops
4) No current treatment for tubal pregnancey that saves embryo

Front 15

Development of the Placenta

Back 15

1) Fetal Portion develops from chorion
2) Maternal Portion forms from functional layer of uterus
3) Embryo connected to placenta via connecting stalk
4) Chorionic villi form from chorion
A) Branches of fetal blood vessels adjacent to the endometrium
B) Blood never mix, but nutrients, oxygen, and carbon dioxide can be transferred

Front 16

Stages of Labor

Back 16

1) Dilation
2) Expulsion
3) Placental

Front 17

Dilation

Back 17

Begins with first regular contractions, ends when cervix is fully dilated by baby's head (longest stage)

Front 18

Expulsion

Back 18

Lasts from full dilation to delivery

Front 19

Placental

Back 19

1) Eliminates placenta
2) Accomplished within 15 minutes after birth of infant

Front 20

Cesarean Section

Back 20

1) Deformed or male-like pelvis
2) Placenta previa
3) Previous C-section
4) Placenta Abruption
5) Atypical presentation of neonate