Female Reproductive System

identify the location, and function of the ovaries

location: pelvic cavity

function: produce, store, and release eggs(oocyte) and hormones: estrogen/progesterone

identify the location, and function of the uterine/fallopian tubes

location: extend from ovaries to uterus

function: pathway for egg, where sperm meets the egg (fertilization)

identify the location, and function of the uterus

location: between bladder and rectum

function: where fertilized egg implants and develops into fetus during pregnancy, or mensturation

identify the location, structure, and function of the vagina

location: cervix to external genitals

function: birth canal, menstrual flow

structure of ovarian follicles

contains an oocyte

surrounded by granulosa cells and theca cells

walls of uterus

inner: endometrium

middle: myometrium (muscular layer)

outer: perimetrium (serous membrane)

compare

• oogonia

• primary oocyte

• secondary oocyte

• polar body

• ovum

• zygote

• oogonia: “stem cell” that eventually becomes a primary oocyte

• primary oocyte: diploid cell that undergoes meiosis 1

• secondary oocyte: results from mei1 - haploid cell; only undergoes meiosis 2 if fertilized

• polar body: haploid cell that’s non functional, degenerates on its own

• ovum: mature haploid cell that results from meiosis 2

• zygote: fusion of sperm into an ovum = results in fertilization and is now a diploid cell

structure and function of mammary glands

structure: adipose tissue, glandular tissue, and CT

function: produce milk during lactation

hormones: stimulated by prolactin (from anterior pituitary) and oxytocin (posterior pituitary)

which gland is stimulated by prolactin (from anterior pituitary) and oxytocin (posterior pituitary)

mammary gland

general timeline of oogenesis (egg production)

starts in the fetus, oocytes are arrested until sexual maturity/puberty (first period), stops at menopause

describe oogenesis in these stages:

• beginning

• puberty/before every period (before ovulation)

• ovulation

where do each of these stages occur in the reproductive system

Beginning - occurs in fetus

• begins with oogonia cells (“stem cells”) in the ovaries of the fetus, these are diploid cells

• these multiple many times via mitosis

• eventually, some of these oogonia will go through meiosis 1 → primary oocytes

• these primary oocytes stay arrested in a follicle until female reaches puberty

Puberty (or before every period now/pre-ovulation) - occurs in the follicle/ovary

• ONLY ONE primary oocyte is activated from alternating ovaries each month

• this singular primary oocyte continues through meiosis 1

• result: 2x haploid cells - however, one is the secondary oocyte and one is the first polar body (due to asymmetrical dividing)

• first polar body dies

Ovulation - occurs in the fallopian tube

• the follicle with the secondary oocyte ruptures and releases it into the fallopian tube

• IF FERTILIZATION OCCURS, meiosis 2 occurs onto secondary oocyte → ovum (still haploid) + 2nd polar body — _{then once sperm releases its DNA into the ovum => it becomes a diploid zygote}

what happen to 2ndary oocyte, corpus luteum, and follicles if fertilization does NOT occur

• secondary oocyte is shedded from uterine lining = period

• corpus luteum disintegrates = drop in estrogen and progesterone

• follicles re-try and start to grow again via FSH

3 phases of the uterine/menstrual cycle

menstrual phase

proliferative phase

secretory phase

describe what happens in each phase of the menstrual/uterine cycle

• include hormones

• fertilization vs. no fert.

menstrual phase

• uterine lining (endometrium) sheds = period

• estrogen + progesterone levels drop

proliferative phase

• estrogen starts to increase and uterine lining starts to re-build after period

secretory phase

• uterine lining reaches it maximum thickness, thanks to progesterone

• lots of blood vessels and nutrients - ready for egg to be implanted

fert: zygote implants into onto endometrium

no fert: back to menstrual phase

3 phases of the ovarian cycle

follicular phase

ovulation phase

luteal phase

describe what happens in each phase of the ovarian cycle

• include hormones

• fertilization vs. no fert.

follicular:

• FSH/LH released from anterior pituitary gland

• follicles in ovaries start to grow (FSH work)

• as time gets close to ovulation, follicle move towards the fallopian tube

ovulation:

• estrogen increases

• LH surge → triggers ovulation _{(remember: only 1 secondary oocyte is released by a mature follicle)}

• mature follicle ruptures = releasing egg

luteal phase:

• ruptured follicle → corpus luteum

• corpus luteum releases more estrogen and progesterone (to help build uterine lining to prepare for reproduction)

no fert: corpus luteum disintegrates = drop in hormones = stop building uterine lining = period

role of FSH and LH

FSH = stimulate Follicles; helps them grow and uses estrogen in follicular phase of ovarian cycle

LH = surge in LH during ovulation phase of ovarian cycle causes release of 2ndary oocyte/egg

role of progesterone and estrogen

released by follicle/corpus luteum in ovaries

progesterone: builds the uterine lining to its maximum thickness (during secretory phase of menstrual cycle)

estrogen: builds uterine lining during proliferative phase of menstrual cycle, helps support progesterone, and stimulates hypothalamus to secrete GnRH