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Human reproduction


The male reproductive system
Male Repro2


A. Penis – the organ that sperm, and urine, passes through
B. Scrotum – A pouch of skin that holds the two testes (also called testicles, or gonads)
C. Urethra – A tube which carries urine, and semen, from inside the body, to the outside
D. Testicles – A pair of organs which produce sperm cells, and the hormone testosterone
Sperm cells carry the chromosomes of the father.
* 23 chromosomes.

* If sperm meets an egg, it will combine its 23 chromosomes with the egg’s 23

* Makes a fertilized egg with 46 chromosomes. Will eventually turn into a baby.


Testosterone is a hormone that starts getting produced at puberty.
* larynx (voicebox) lengthens, so the voice deepens

* enlarges size of penis and testicles

* causes facial and body hair to grow

* increases length of bones, and helps increase muscle mass

* causes skin to thicken and become more oily (this can lead to acne)
Vas deferens – A tube that carries sperm from the testicles to the urethra,

Seminal vesicles – Glands at the back of the bladder. They secrete semen.

Prostate gland – Also secretes semen


The female reproductive system


1. Vagina (birth canal) – A muscular tube leading inside a woman’s body.

Where sperm enters a woman. Also is where a baby is born from.
2. Cervix – The muscular wall at the end of the vagina. It has a tiny hole that sperm can swim through.
3. Uterus (womb) – sperm swim up through the womb:
*  some sperm swim left, and some swim right.

If a woman becomes pregnant, the fetus will attach to the wall of the uterus and grow here.


5. The Endometrium – the lining of the uterine walls, filled with tiny blood vessels.

(a) Each month this thickens, in anticipation of pregnancy.

(b) If pregnancy occurs, then the endometrium is kept. Used to nourish the growing fetus.

(c) If pregnancy doesn’t occur then the endometrium is shed,
and expelled through the cervical opening, out through the vagina.
This process is called menstruation

6. Myometrium – the muscular wall of the uterus
7. Fallopian tubes – These carry the egg from the ovary, towards the uterus.

(a) sperm swim up into these tubes.
If the woman has recently released an egg, this is where the egg and sperm meet.
8. Ovary – these are where eggs are stored.
9. Ovulation: About every 28 days, a woman releases one egg

* sometimes from the left ovary, sometimes from the right.
* If the egg becomes fertilized then she is pregnant.
10. Implantation – when the zygote (fertilized egg) implants into the endometrium

Menstrual cycle

Menstrual cycle diagrams



Amniocentesis Amniocentesis image006

Reproductive technology

artificial insemination 3

1. Artificial insemination: using sperm from a donor
A. The woman takes a hormone. that stimulates her ovary to ripen several eggs.
B. Doctors watch what is happening inside by using ultra-sound
C. Ovulation: the ripe egg is released
D. Sperm is collected from the man.

E. They look at sperm under a microscope, and select healthy sperm.

F. They use a thin tube to insert the sperm into the vagina, right by the cervix.



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