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Female duct system

Mullerian

Male duct system

Wolfian ducts

Sex-determining region, on the Y chromosomes- allows males to be males

SRY

Makes testosterone (pause the development of the internal male genetalia) , DHT (stronger form of testosterone- helps to develop external gentalia, 5 alpha reductase will change testorone into di-hydrotestosterone) AMH/MIF (Mullerian inhibiting factor, Anti-Mullerian hormone, gets rid of the mullerian ducts)

SOX 9

Seminiforous tubules: this is where the sperm cells are made and they have the seritoli cells (they make the nutrients for the sperm cells)

Testes in males

Making sperm (spermatogensis): primary spermatocyte-then we are going to get a secondary spermatocytes (2) and these each break into two cells called spermatid- has to do more growth to become a spermatozoan (when the spermatid becomes the spermatozoan: this is called spermiogenesis). This results in four sperms being made per cycle

Spermatogenesis vs spermiogenesis

A convoluted tubule in each testis; carries sperm to vas deferens

Epididymis

Takes the sperm out of the body

Vas deferens tube

Seminal vesicle (makes the most of the semen), the prostate gland and the bulbs uretho gland

The three semen glands

The corpus spongiosium and the corpora cavernosa (swells up when the blood comes into it, happens during an erection)

Two kinds of tissues in the penis

External: penis and internal male genatalia: testes and the scrotum

The internal and external male genatalia

The internal female gentalia: the vagina, the uterus, the ovaries external female gentalia: the labia majora (urethal opening and the vaginal opening) and the labia minora, the clitoris (sex organ, sex pleasure)

The internal female getalia and the external femalegentalia

Term for all the female gentalia

Valva

Has a fleshy layer: called the endometrium and the other one that doesn’t fall out is called the myometrium (muscle, doesn’t muscle, this is the stuff where you get the uterine contractions)

The uterus:

Making of the eggs in females

Oogenisis

Germ cell- oogonium (happens in womb)and develops into primary oocyte M1: primary oocyte becomes secondary oocyte and polar body

Meiosis one in females

The secondary oocyte: this becomes a polar body and ootid and the ootid becomes the ovum

Meiosis two

They have thecal cells: that make androgens and they get convereted into estrogens by aromatase

The ovaries

Before birth: meiosis occurs- but stop at prophase 1 (nothing occurs during childhood). from puberty to menopause: complete meiosis one, but meiosis II will not be completed until fertilized

Meiosis in females

Arousal (parasympathetic) Erection (blood + swelling) Lubrication Orgasm (heart rate up, breathing heavy, pupils dilating: emission (movement from glands to vas deferens), ejaculation (vasdefrens to outside world sperm) (sympathetic) Resolution (sympathetic)

The Male sexual cycle

1. Desire 2. Arousal (lubrication, vagina swells up and cliotris errects) 3. Orgasm 4. Resolution

The female sexual cycle

Sperm hits the vagina and then it swims because the the inhibitory substance washes off- has something called the acrosome (sac of bitter enzymes)

Capacitation Reaction

The acrosome is used to break through the corona radiata and the zona pelucida and binds its head to the egg using the bindin protein

Fertilization

Prevent multple sperms from fusing with the egg The cortical reaction: uses calcium to make its outer layer harder Increase the distance between the egg and the outer layer

Two ways to block polyspermy

In each of the stages more and more granulosa cells (keep piling up): 1. primordial follicle 2. primary follicle 3. secondary follicle 4. the Graffian follicle (this is the egg to be ovulated)- this has two layers of cells (the corona radiata and the zona pellucida)

Development of the egg

When the egg leaves the ovary, the structure that remains gets turned on by lutenizing horomone, and it is going to release estrogen and progesterone to make sure that the lining (endometrium) of the vagina does not fall off, need that to prevent the zygote from falling off

The corpus luteum

This is what the corpus luteum becomes when one is not pregnant- and then you have menstration

Corpus Albicans

Starts ovulation

Lutenizing hormone

Formation of the embryo 1. zygote 2. morula 3. blastula (this forms the blastocyst has the ICM- this forms the embryo)

The embryogenesis

The membrane that forms the wall of the blastocyst in early development; aids implantation in the uterine wall

Trophoblast

This allows the fetus to interact wth the mom: give it o2, feed it, get rid of waste) without the blood to mixing (because the fetus has the DNA of the father, the mom is going to develop anti-bodies to it)

The placenta

The ectoderm, the mesoderm and the endoderm (comes from the ICM) the ectoderm: hair, epithelium (nasal, oral, and anal) , cornea, the nervous system, mesoderm: blood, blood vessels, bone, cartilage, ligaments, tendons, fat, lymph, muscles, urogenital system (urerter, gential system), dermis endoderm: the bladder,the lungs, the pancreas, the stomach, and the epithelieum of GI tract

Three layers of the blastocyst

Formation of organs happens by the end of the first trimester of pregnancy

Organogensis

The neural plate folds into the neural tube to form the brain and the spinal cord off from the neural plate comes the neural crest cells- make up the PNS

Neuralation

The baby falls down on the cervix and the uterus starts to contract, and then this sends a signal up to the brain, to release more oxytocin, this triggers more contractions (positive feedback, happens till the baby comes out) the cervix dilates

Birth (Partution)

When the kids out of the mom, the mammary glands make milk something called prolactin: helps you to make milk the oxytocin: this allows for milk let down

Lactation

1. pubertal growth spurt 2. more muscle 3. voice deepens 4. pubic hair and body hair increases 5. Ephesal plate fusion 6. Caused by Testosterone

Male (secondary sex characteristics)

1. caused by estrogen 2. pubertal growth spurt 3. the breast enlarge 4. pubic and body hair increases

Female (secondary sex characteristics)

Uterine cycle and the ovarian cycle

Two phases of the menstrual cycle

Menstruation (makes sure that the lining is nice and clean ( 5 days to dump out of all the lining) ( 5 days) Prolierative phase (regrow line) ( 9 days) Secretory phase ( the lining gets stocked with all kinds of fats and nutrients [last 14 days]

Uterine cycle

Follicular phase: you have the egg growing (estrogen increases) [13 days] Ovaulatory phase: egg comes out of ovary and going into the tube [1 day] (LH increase) Luteal phase: corpus luteal starts to grow so that you don’t get menstruation (estrogen and progesterone increase a lot) [14 days]---- not pregnant, luteal goes away and goes into menstration

Ovarian Cycle

Adjacent to the seminiferous tubules and they release testosterone

The Leydig cells

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