Sexual Reproduction

Abstinence

Not having sexual intercourse. No risk.

Detection of Ovulation

abstain from sexual intercourse on the days of ovulation. No pills. Not reliable.

Coitus interruptus

Is the removal of the penis just before male orgasm so that ejaculation takes place outside the vagina. No side effects or costs. Very unreliable.

Contraceptive pill

hormonal alteration preventing ovulation. Reliable and reduces incidence of ovarian and uterine cancer. Dr prescription and possible side effects.

Hormone implant

soft plastic stick about 4cm long which is inserted beneath the skin on inner side of upper arm that slowly releases progesterone. Lats 3 yrs cheap, nearly 100%. Menstrual irregularities.

Condom

thin latex rubber that is rolled on to the erect penis. It prevents semen from entering vagina. Protection against STI’s. Can tear or slip off.

Diaphragm

Thin rubber cap that fits across the top of vagina. Has to be left six hours after intercourse.

Cervical cap

Fits over cervix.

Female condom

Lubricated polyurethane sheath that lines vagina. Stronger than male condoms. Good protection against STI’s. More expensive then male condoms.

Spermicide

Contains a substance that immobilises and destroys sperm. Reacts with moisture in the vagina and forms a physical bubble barrier. Very unreliable, no protection.

Male sterilisation

Vasectomy involves removal of a small piece of vas deferens. Nearly 100% effective. No protection.

Female Sterilisation

Each tube is cut, a small piece is removed the ends are tied. Nearly 100% effective. No protection.

Emergency contraceptive pill

A single tablet of progesterone works by preventing or delaying ovulation. No protection.

Intrauterine device

Are small devices made of plastic, and often containing copper, that are inserted into the uterus. Must be inserted by doctor. No protection.

Chlamydia

Caused by a highly specialised bacterium, Chlamydia Trachomatis. Transmitted by vaginal/anal sex. Antibiotics, can be cured.

Gonorrhoea

caused by a bacterium Neisseria gonorrhoea. Transmitted through sex. Antibiotics. Later stages may require surgery. Can be cured.

Genital Herpes

Skin to skin contact genital/oral/anal sex. No cure. Meds to reduce pain. Saline dressings and antiviral drugs.

Genital warts

Caused by a virus, human papillomavirus. (HPV). Passed on by sexual partner.

Human immunodeficiency virus (HIV)

Body fluid from one person enters bloodstream or mucus membranes of another. No cure, antiretroviral drugs that inhibit reproductive cycle of virus.

Chlamydia Symptoms

Men: mucus like discharge, burning sensation.

Women: Often no symptoms. pelvic inflammatory disease.

Gonorrhoea symptoms

Males: inflammation of urethra causes burning and pain.

Females: Pain in oviducts and abdominal.

Syphilis symptoms

Small sores (chancers). Skin rashes.

Genital herpes symptoms

cold sores, blisters on genitals, Flu symptoms, rash.

Genital warts symptoms

warts in genital area.

Human immunodeficiency Virus Symptoms

Flu symptoms, immune system damaged (no resistance against infections).

Ultrasound

ultrasound uses inaudible high frequency sound waves to produce an image of foetus. It is used throughout the pregnancy. It cannot diagnose all abnormalities.

Ultrasound (Why)

Confirming stage of pregnancy, determining number of foetuses, identifying abnormalities of the cervix or uterus, monitoring growth of foetus, determining gender, evaluating anatomy, identifying birth defects.

Amniocentesis

Ultrasound to guide the needle through the abdominal wall into the amniotic cavity. Between 16th and 20th weeks of pregnancy. Amniocentesis involves a small risk of infection, miscarriage or damage to baby.

Amniocentesis (Why)

Cells can be examined for biochemical defects and for abnormalities in number or structure of chromosomes.

Chorionic villus sampling

CVS obtains a specimen of foetal cells from the chorion, cells are then examined. 9-19 weeks of pregnancy. The risk of miscarriage following the procedure is 2% cannot diagnose spina bifida.

Chorionic villus sampling (Why)

Cells can be examined for biochemical defects and for abnormalities in number or structure of chromosomes.

Blood tests

blood test of the mothers blood identify if there is an increased chance of the baby having a certain disorder. 10 weeks of gestation. Just screening cannot diagnose.

Blood test (Why)

Down syndrome (trisomy 21)

Edwards syndrome (trisomy 18)

Patau syndrome (trisomy 13)

Turner syndrome

Foetal blood sampling

blood is taken from the umbilical cord or from foetal blood vessel. 18 weeks or later. Carries higher risk of miscarriage, infection, blood loss and premature rupture of amniotic sac.

Foetal blood sampling (Why)

used to diagnose chromosomal abnormalities and foetal anaemia, check foetal oxygenation, identify infections, give medications.

Testes

production of sperm and hormones

Epididymis

Highly folded tubule that stores sperm while they finish maturing.

Vas deferens

carries sperm away from testis to the urethra

Seminal vesicles

secretes a fluid rich in sugars and makes up 60% of semen.

Prostate gland

secretes thin milky, alkaline fluid that also becomes part of semen this helps activate sperm.

Bulbo-urethral gland

secrete clear mucus, secretion acts as a lubricant precedes the emission of seminal fluid.

Urethra

Is a duct for transporting urine and sperm outside the body.

Scrotum

A skin covered pouch where testes are held. Allows testes to lie outside the body.

Foreskin

Covers the head or end of penis, may be removed by circumcision.

Erectile tissue

Is in three cylinders.

Penis

Is the organ that passes urine and transfers sperm into female.

Head of sperm

Acrosome (Digestive enzyme)

Genetic information

Body of sperm

Mitochondria energy

Tail of sperm

Flagellum used for propulsion

Pathway of sperm

Testes→ Epididymis→ Vas Deferens→ Seminal vesicles→ Prostate gland→ Bulbo-Urethral gland→ Urethra→ Out of body.

Ovaries

Ovaries produce female gametes

Fallopian tube

Funnel like opening, carry egg from ovary to uterus.

Uterus

A single hollow, pear shaped organ, smooth muscle, soft mucus membrane called endometrium. Protects and nourishes the developing foetus during pregnancy.

Cervix

Canal leading to outside of body

Vagina

Is capable of considerable stretching. Receiving the penis, enlarges to form birth canal during childbirth.

Labia Majora

two fleshy fold of skin, made of fat and fibrous tissue glands produce oily secretions.

Labia Minora

Surrounds space which urethra and vagina open.

Clitoris

Contains erectile tissue, blood vessels and nerves. Very sensitive to touch, engorged with blood when stimulated.

Pathway of Ova

Ovary→ Fallopian tubes→ Uterus→ cervix→ vagina→ out of body

Where does oogenesis occur?

In the ovaries

oogonia forms

primary oocytes prior to birth

After puberty each primary oocyte completes

its development to form a secondary oocyte and up to three polar bodies.

The secondary oocyte is released during

ovulation and completes meiosis if it is fertilised

Oogonium mitosis into (2n)

oogonium 3x (2n)

oogonium undergoes meiosis 1 to form

Primary oocyte

Primary oocyte (2n) is held at prophase until

puberty and is reactivated at Menarche.

Secondary oocyte (n) occurs at

meiosis 2, If fertilised meiosis 2 is completed.

Secondary oocyte (n) creates

ootid and second polar body

ootid (n) undergoes maturation to form

ovum

At the end of oogenesis

one ova is produced alongside 3 polar bodies.

Spermatogenesis occurs inside the

seminiferous tubules of each testis

Spermatogenesis results in

four spermatozoa from each spermatogonium

Spermatogonium (2n) undergoes mitosis to form

Primary spermatocyte (2n)

Primary spermatocyte (2n) undergoes meiosis 1 to form

secondary spermatocyte (n)

Secondary Spermatocyte (n) undergoes meiosis 2 to form

Spermatid 4x(n)

Spermatid undergoes maturation to form

Spermatozoa

Two hormones released by the pituitary gland that effect gonads are

Follicle-stimulating hormone and Luteinising hormone

As progesterone increases

Luteinising hormone decreases

Progesterone is secreted by

the corpus luteum

oestrogen is secreted by

the corpus luteum

The pituitary gland also releases

prolactin and oxytocin

Follicle-Stimulating hormone (Female)

Stimulates the development and maturation of ovarian follicle.

Follicle-Stimulating hormone (Males)

Stimulates the epithelial tissue of the seminiferous tubules in the testes to produce sperm.

Luteinising Hormone (Females)

Promotes final maturation of the ovarian follicle, ovulation, and, the formation of the corpus luteum.

Luteinising Hormone (Males)

Stimulates cells in the testes to secrete the hormone testosterone

Prolactin (Female)

Important in the preparation and maintenance of milk production.

Oxytocin (Females)

Promotes the movement of milk in the breasts.

Oxytocin (males)

Role in the movement of sperm and the production of testosterone in the testes.

Testosterone

Is important for sperm production

Oestrogen

prepares the endometrium.

1. Ovarian Cycle

Cells start to form around the ova in a single layer to form a primary follicle

2. Ovarian cycle

The primary follicle enlarges and cells divide to form a secondary follicle

3. Ovarian cycle

A fluid is produced which sees the ova move to the outskirts of the follicle.

4. Ovarian cycle

At ovulation the follicle ruptures. Heads in direction of uterine tubes.

5. Ovarian cycle

(yellow body) Remaining follicle forms blood clot which is reabsorbed by follicles. Release progesterone and oestrogen.

6. Ovarian cycle

(White body) Fibrous mass of scar tissue.

Menstruation 1-4 days

Uterine bleeding accompanied by shedding of the endometrium

Preovulation 5-12 days

Endometrial repair begins, development of ovarian follicle, uterine lining gradually thickens.

Ovulation 13-15 days

Rupture of mature follicle, releasing egg.

Secretion 16-20 days

Secretion of watery mucus by glands of endometrium, cervix and uterine tubes, movement and breakdown of unfertilised egg, development of corpus luteum.