Chapter 23.2: Female Reproductive System

General Anatomy

- Ovaries: produce oocytes and hormones

- Uterine tubes: transport oocytes from ovaries to uterus

- Uterus: pathway for sperm to reach ovaries and development of fetus

- Vagina

- Mammary glands Vagina

Uterine (fallopian) tube

Ovary

Uterus

Cervix

Urethra

Labium minus

Anatomy of Ovaries

Mature (graafian) follicle

Ruptured follicle

Ovulation (expulsion of a secondary oocyte)

Degeneratingcorpus luteum

Corpusluteum

Growing follicles

Oogenesis

- The process by which ovaries produce eggs- This begins before birth

- Three stages:- Meiosis I- Meiosis II- Maturation

Meiosis I

- During fetal development- Oogonium (2n) develop into primary oocytes (2n)- About 200,000 to 2,000,000 developed at time

of birth

- At puberty- 40,000 primary oocytes remain- Hormones initiate completion of Meiosis I

to produce secondary oocyte (n) and 1st polar body (n)

Oogonium

2n

Primary oocyte

2n

n n

Secondaryoocyte

Firstpolar body

Meiosis I

During fetal development meiosis I begins.

After puberty, primary oocytes complete meiosis I, which produces a secondary oocyte and a first polar body that may or may not divide again.

Meiosis II

- Secondary oocyte (n) begins Meiosis II- Occurs in the ovary

- Ovulation- Secondary oocyte released into fallopian tube- Only about 400 go through this

- Fertilization- Sperm penetrates secondary oocyte- Meiosis II resumes- Produces ovum (n) and second polar body (n)- Sperm and ovum nuclei join to produce a

zygote (2n)

Oogonium

2n

Primary oocyte

2n

n n

n n

n

nn

2n

n

n

Secondaryoocyte

Firstpolar body

Spermcell

Secondaryoocyte

Fertilization

Secondpolar body

Ovum

Zygote

Meiosis I

Meiosis II

During fetal development meiosis I begins.

After puberty, primary oocytes complete meiosis I, which produces a secondary oocyte and a first polar body that may or may not divide again.

The secondary oocyte begins meiosis II.

A secondary oocyte (and first polar body) is ovulated.

After fertilization, meiosis II resumes. The oocyte splits into an ovum and a second polar body.

The nuclei of the sperm cell and the ovum unite, forming a diploid (2n) zygote.

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Ovulation

Uterine Tubes and Uterus

- Two uterine (fallopian) tubes- Transport secondary oocytes to

uterus

- Each tube has a open, funnel- shaped end called infundibulum- Contain fimbriae that sweep oocyte

into fallopian tube

- Fertilization occurs in the tubes- Fertilized ovum implanted into uterine wall

Infundibulum ofuterine tube

Cervix of uterus

Vagina

Uterine (fallopian) tube

Ovary

Fimbriae of uterine tube

Body of uterus

Vagina

- Extends from the exterior of the body to uterine cervix

- Vaginal mucosa produces organic acids- Prevents microbial growth- Harmful to sperm

- Surrounded by smooth muscle to allow intercourse and child birth

Mammary Glands

- Modified sweat glands that produce milk

- 15-20 lobes which contain alveoli

- Milk secreting glands

- Milk production stimulated by prolactin and milk secretion stimulated by oxytocin

Lobule containing alveoli

Milk duct

Nipple

Adipose tissue in subcutaneous layer