Reproduction , fertility and contraception

What does reproduction involve?

The joining of two gametes, the sperm and the ovum (the egg)

What are the components of the male reproductive system?

Bladder, urethra, penis, scrotum, testis, sperm tube, prostate gland

What is the bladder?

Muscular bag to store urine

What is the urethra?

Tube through the penis which carries sperm out of the penis

What is the penis?

Organ that releases sperm into the vagina

What is the scrotum?

Sac that holds testes at slightly lower than body temperature.

What are the testes?

Produce sperm

What is the sperm tube?

Tube which carries sperm from testes to urethra

What is the prostate gland?

Adds fluid to nourish sperm (semen)

How are sperm adapted?

1. They have a flagellum to help them swim

2. Mitochondria for energy production

3. Haploid nucleus

What are the components to the female reproductive system?

The oviduct, ovary, uterus wall, uterus, cervix, vagina

What is the oviduct?

Carries ova to the uterus

What is the ovary?

Where the ova are produced

What is the uterus wall?

Where the placenta forms after fertilisation

What is the uterus?

Where the foetus develops and is nourished

What is the cervix?

The opening of the uterus- it widens during birth

What is the vagina?

Where the penis is placed during intercourse

What is the male sex hormone?

Testosterone and it is produced in the testes

What is the female sex hormone?

Oestrogen and it is produced in the ovaries

What happens during fertilisation?

The fusion of an ovum and a sperm in the oviduct

What are the steps of fertilisation?

Haploid nuclei of ovum and sperm fuse and form a diploid

fertilised egg is now a zygote

Zygote divides by mitosis, form an embryo as it travels down oviduct to the uterus

What are the adaptations of the placenta?

1. There is a rich network of blood vessels to increase blood flow

2. There is a large number of villi to increase surface area

3. Large SA needed for exchanging dissolved nutrients

What is the umbilical cord?

Contains the umbilical artery and vein to allow for exchange of gases, nutrients, waste products between the mother and foetus

What is the amnion?

The membrane containing the amniotic fluid protecting the embryo

What is the amniotic fluid?

Cushions the developing embryo

What is the menstrual cycle?

The renewal of the blood rich lining of the uterus- this is to provide a suitable environment for a developing embryo

How long does the menstrual cycle last?

Approximately 28 days

What are the stages of the menstrual cycle?

Menstruation (1-5), following menstruation (6-13), ovulation (13-15)

What is menstruation?

The breakdown and removal of the uterus lining at the end of each cycle. Lasts from puberty to 44-55 years

What happens in the days after menstruation?

The rebuilding of the uterus lining to prep for fertilisation

What is ovulation?

The release of an ovum from the ovary

What does oestrogen do in the menstrual cycle?

Causes the repair and build up of uterus lining and stimulates ovulation

What does progesterone do in the menstrual cycle?

Maintains the build up of uterus lining and prepares uterus for pregnancy

What time is fertilisation most likely to occur during?

Days 13-15

What do fertility drugs do?

Increase egg production and release

What are the steps of in vitro fertilisation?

Stimulation, egg retrieval, insemination, pregnancy

What are sperm cells?

specialised cells formed by meiosis

Where does fertilisation take place?

oviducts when the haploid sperm and egg nuclei fuse to give a diploid zygote

What are some causes of infertility?

1. Blocked Oviducts

2. Eggs are not released

3. Low Sperm Count

4. Impedience

What do male condoms do?

Barrier to prevent sperm entrance

What are the pros and cons of male condom?

1. Easily obtained

2. Protects against STIs

3. Unreliable if not used properly

What do female condoms do?

Barrier for sperm passing

What are the pros and cons of female condoms?

1. Easily obtained

2. Protects against STIs

3. Unreliable if not used properly

What do contraceptive pills do?

prevents releasing eggs and changing hormone levels

What are the pros and cons of contraceptive pills?

1. Very reliable

2. Weight gain

3. Risk of blood clots

4. Need to remember to take pills

What do implants do?

Small 4cm tubes inserted under the arm and releases hormones over longtime period to prevent the development and release of eggs

What are the pros and cons of implants?

1. Very reliable

2. Can work up to 30 years

3. Prevents menstruation

What do vasectomies do?

Cutting off sperm tubes and prevents it from entering the penis

What are the pros and cons of vasectomies and female sterilisation?

1. 100% reliable

2. Impossible to reverse

What does female sterilisation do?

Cutting off oviducts prevents fetilisation