Chapter 26 - Reproduction and Development (FEMALE)

What are the three sets of structures that both male and female reproductive systems consist of?

gonads, internal genitalia, external genitalia

Somatic cell

regular body cell; diploid (2n)

Germ cell

Cell that can become a gamete; starts at 2n —> 1n

Mature gamete

Fully formed egg or sperm; Haploid (1n)

Zygote

a diploid cell resulting from the fusion of 2 haploid germ cells (egg + sperm cell)

gonad

organ that produces gametes (testis/ovary)

vagina function

menstruation, intercourse, and childbirth

Cervix function

facilitates passage of sperm from vagina —> uterus

Cervical secretions

mucus barrier b/w vagina and uterus from mucus glands

Uterus

where embryo implants and develops during pregnancy

Three layers of the uterus

connective tissue covering, myometrium, endometrium

Myometrium

smooth muscle that lies in the middle layer of uterus

Endometrium

consists of glandular and luminal epithelium (changes over menstrual cycle; hormonal regulated)

Fimbriae

onnects ovary with fallopian tube; helps uptake ovulated egg

Ovary

female gonad; produces hormones, matures and ovulates eggs for fetilization and pregnancy

Fallopian tube

where fertilization occurs; cfacilitiates embryo transport to uterus

Characteristics of fallopian tube

consists of two smooth muscle layers (longitudinal and circular)
+ ciliated epithelium lines inside tubes

What will happen if there are abnormal cilia secretion and movement and/or fallopian tube contraction?

implantation of fertilized egg in fallopian tube instead of the uterus —> ectopic pregnancy
OR fertilization may not even happen —> infertility

Outer cortex of ovary has

follicles in various stages

inner medulla of ovary has

nerves and blood vessels

2 Major functions of ovaries

1. produce hormones
2. mature and release eggs

primordial follicles are quiescent to

establish the ovarian reserve

oocyte

immature egg

Granulosa cells

oocyte surround cells that respond to FSH
has enzymes that converts androgens —> estrogens

Theca cells

makes androgens

atresia

natural death of follicle

among 1-2 million primordial follicles, what happens to majority of follicles?

atresia

what is secreted during follicle growth

estradiol

estradiol

stimulates surge of LH from anterior pituitary

Ovulation

rupture of follicular wall, oocyte meiosis, lutenization

luteinization

differentiation of theca cells and granulosa cells into luteal cells

luteinization forms

corpus luteum

corpus luteum secretes

progesterone, estrogen, and inhibin

effect of progesterone

makes uterine more receptive for supporting embyo implantation

Why can we have a 28-day menstrual cycle if it takes >200 days for folliculogenesis

There are many follicles growing continuously in waves (not open at a time)

3 stages of ovarian cycle

follicular phase, ovulation, luteal phase

3 stages of uterine cycle

menses, proliferate phase, secretory phase

Theca cells have which receptors

LH

Granulosa cells have which receptors

FSH

Theca cells produce

androgens

Granulosa cells produce

aromatase

aromatase

enzyme that converts androgens —> estrogens
+ provides nutrients to oocyte

gonadotropin

any of a group of hormones secreted by the pituitary

Which gene encodes aromatase?

CYP19A1

Polycystic Ovary Syndrome (PCOS)

Reproductive endocrine disorder when there are many immature follicles that NEVER finished development—> no ovulation

Characteristics of PCOS

anovulation, hyperandrogenism, polycystic ovaries (and sometimes insulin resistance and obesity)

____ induces the LH surve via ____ feedback mechanism

estrogen; positive

how do birth control pills work?

prevents ovulation by using negative feedback (high levels of progesterone)

3 types of steroid hormones secreted by the gonads

androgen, estrogen, progesterone

3 types of peptide hormones secreted by the gonads

AMH, inhibin, activin

capacitation

preparing sperm for fertilization after ejaculation

Where does capacitation of sperm occur

uterus and fallopian tubes

cortical reaction

prevents polyspermy (blocks other sperms)

what facilitates embryo transport

cilia and smooth muscles

Which hormones primarily regulate uterine receptivity

estrogen + progesterone

blastocyst

zygote that undergone mitosis

placenta is differentiated from

trophoblasts

placenta links the

fetus and the mother

placenta forms the

blood placenta barrier (BPB)

Which hormones does the placenta secrete to prevent menstruation

hCG, hCS, estrogen, progesterone

Trophoblast

cells forming the outer layer of a blastocyst

hCG function

maintains corpus luteum during early pregnancy
- corpus luteum keeps producing hormones that prevent menstrual cycle to begin

what does a pregnancy test detect?

hCG in urine or blood through antibodies

what three layers does the inner cell mass of the blastocyst make?

ectoderm, mesoderm, endoderm

what area softens/stretch/dilates during parturition

cervix

what area contracts during parturition

uterine

What factors trigger labor?

decrease in estrogen and progesterone
oxytocin
CRH

CRH function

Production of prostaglandin and oxytocin

prostagladin function

uterus muscle contraction (positive feedback loop)

progesterone function during pregnancy

conversion from milk duct —> secretory structure

prolactin function

stimulates milk production

how is prolactin inhibited during non-pregnancy

PIH (prolactin inhibiting hormone) from hypothalamus

Oxytocin function

uterine contraction + stimulates milk duct contraction

menarche

first mensrual period

Requirements of puberty

maturation of hypothalamus and pituitary (GnRH —> FSH and LH) + maturation of gonads for sex hormones

at puberty, ____ increase their pulsatile

GnRH secretion neurons

Which adipose tissue hormone is aso involved to contorl puberty?

leptin (BMI, fertility)

Around what age does ovarian aging begin?

mid 30s (occurs around 45-50)

Cause of ovarian aging

insufficient number of follicles OR worsened quality of oocytes

determinants of quality of oocytes

physiological, pathological, exposure to toxicants (ex. radiation)

Which stage of follicle is most important to determine menopause?

primordial follicles (ovarian reserve) since depletion = menopause