Reproductive System and Prenatal Development

Flashcards for prenatal and postnatal development, fertilization, and reproductive organs

Fertilization

The union of a sperm and a secondary oocyte.

Prenatal Period

Period from fertilization to birth.

Postnatal Period

Period from birth to death.

Pregnancy

Developing offspring in the uterus.

Cleavage

Rapid cell division and distribution of the zygote's cytoplasm into smaller cells.

Blastomeres

Cells produced during cleavage.

Zygote

Fertilized egg.

Morula

Solid ball of cells.

Blastocyst

Hollow ball of cells that implants in the uterus.

Trophoblast

Cells forming the wall of the blastocyst; develops into structures that assist the embryo and produces hCG.

Placenta

Vascular structure formed by cells of the trophoblast and endometrium.

hCG Secretion

Maintains the corpus luteum and inhibits FSH and LH.

Relaxin

Inhibits uterine contractions and relaxes pelvic ligaments.

Placental Lactogen

Stimulates breast development.

Embryonic Stage

Extends from the beginning of the second week through the eighth week of prenatal development.

Umbilical Cord

Carries nutrient-rich, O2-rich blood from the placenta to the fetus.

Umbilical Arteries

Carries blood containing CO2 and wastes from the fetus to the placenta.

Colostrum

Thin, watery fluid rich in proteins and antibodies, produced before milk.

Sperm

Male sex cells

Gametes

Sperm and eggs (ova/oocytes)

Haploid cells (1N)

23 Chromosomes

Somatic cells

46 Chromosomes

Apoptosis

Process of programmed cell death

Meiosis

Creates cells and produces genetically variable cells

Mitosis

Produces identical cells

Testes

Primary sex organs (gonads) are the 2 testes, in which sperm cells (spermatozoa) & the male sex hormones

Spermatic cord

Connects the testis to the body cavity and contains vas deferens, cremaster muscle, a pampiniform plexus, and a testicular artery.

Spermatogonia

Diploid stem cells; divide to form 2 daughters, one of which stays behind and the other becomes a Type A spermatogonium that begins undergoing meiotic division

Interstitial cells (Leydig)

Produce the androgens

Epipdymis

Temporary storage site for sperm

Sertoli cells

Protect Developing Spermatocytes and provide a Blood-testis barrier

Acrosome

Head contains 23 chromosomes

Epididymis

Long, coiled tube located at the back of each testicle

Seminal vesicles

Seminal vesicles secretions when the sperm enters

Seminal vesicles

Secretes fructose and prostaglandins – 60% of the total ejaculate

Prostate Gland

The ducts of the gland open into the urethra

Prostate Gland

Secretes a thin, milky, alkaline fluid

Bulbourethral (Cowper’s) Gland

Inferior to the prostate gland

Bulbourethral (Cowper’s) Gland

Secretes relatively thin, mucus-like fluid

Semen

The fluid that the urethra conveys to the outside during ejaculation is called semen

Dartos

Wall of scrotum (smooth muscle); contracts in cooler temperatures

Maternal inheritance

mitochondria always come from mom; mitochondria contain mitochondrial DNA

Monozygotic (Indentical Twins)

Sperm + Oocyte → (mitosis) → 2 cell embryo → (separated) → becomes individual (but both identical)

Broad ligament

Largest also attached to the uterine tubes and uterus

Suspensory ligament

Holds the ovary at the upper end

Ovarian ligament

Holds the ovary at the lower end

Progesterone

Stops menstruation → stops lining, and prevents the loss of a baby

Graafian follicle

FULLY mature follicle

Follicle matures

As a follicle matures, its primary oocyte completes meiosis I, giving rise to a secondary oocyte and a first polar body

Fornices

Recesses between upper vaginal wall and cervix

Vaginal orifice

Partially enclosed by hymen

Vagina

Fibromuscular tube that conveys uterine secretions, receives the penis during sex, and provides an open channel

Glycogen granules

Lactate production (is a base for the vagina since it is acidic)