5.3 Homeostasis and response (hormones in human reproduction and contraception)

Question 1

What is the function of male reproductive organs during puberty?

Answer 1

to develop secondary sexual characteristics

Question 2

What is the function of female reproductive organs during puberty?

Answer 2

to develop secondary sexual characteristics and the maturation of eggs

Question 3

What is the main male reproductive hormone?

Answer 3

testosterone - which controls sperm production

Question 4

What is the main female reproductive hormone?

Answer 4

oestrogen - which is involved in the menstrual cycle

Question 5

What is the menstrual cycle?

Answer 5

The monthly cycle of physiological changes that occur in females, involving the shedding of the uterus lining (menstruation) and ovulation

Question 6

Describe the events of the menstrual cycle?

Answer 6

• The uterus lining thickens and an egg begins to mature in the ovaries
• An egg is released from one of the ovaries, and the uterus lining remains thick
• If the egg is fertilized, pregnancy may occur. If not, both the egg and the uterus lining are shed during menstruation

Question 7

What is ovulation?

Answer 7

the release of a mature egg from the ovaries, which occurs approximately every 28 days

Question 8

What is menstruation?

Answer 8

the shedding of the uterus lining

Question 9

Name the four main hormones involved in the menstrual cycle?

Answer 9

• oestrogen
• progesterone
• follicle stimulating hormone (FSH)
• Luteinising hormone (LH)

Question 10

What is the role of FSH in the menstrual cycle?

Answer 10

it controls the maturation of eggs within the ovaries (inside a follicle)and triggers the production of oestrogen by the ovaries

Question 11

What is FSH secreted by?

Answer 11

the pituitary gland

Question 12

What is the role of oestrogen in the menstrual cycle?

Answer 12

• oestrogen causes the regrowth of the uterus lining and triggers the production of LH and restricts the release of more FSH

Question 13

What is the role of LH in the menstrual cycle?

Answer 13

LH is produced in the pituitary gland as a result of oestrogen. Its release triggers ovulation

Question 14

Where is LH produced?

Answer 14

in the pituitary gland

Question 15

What is the role of progesterone in the menstrual cycle?

Answer 15

It is secreted from the follicle of the ovary. It sustains the uterus lining and inhibits FSH and LH

Question 16

What is contraception?

Answer 16

Any method of preventing pregnancy

Question 17

What are the two types of oral contraceptives?

Answer 17

• combined contraceptive pill (contains oestrogen and progesterone)
• mini pill (contains only progesterone)

Question 18

How does the contraceptive pill prevent pregnancy?

Answer 18

• It inhibits FSH so eggs do not mature
• Prevents the development of the uterus lining, so eggs cannot implant
• increases the thickness of cervical mucus - so immobilises sperm cells

Question 19

What is the contraceptive patch?

Answer 19

• It is a patch that contains both oestrogen and progesterone that is placed on the skin for 7 days at a time

Question 20

What is the contraceptive implant?

Answer 20

A small rod inserted under the skin which continuously releases the hormone progesterone - lasts for 3 years

Question 21

What is the contraceptive injection?

Answer 21

An injection containing the hormone progesterone - lasts for approximately 3 months

Question 22

What does IUS stand for?

Answer 22

intrauterine system

Question 23

What is the IUS?

Answer 23

A small plastic device that is inserted into the uterus. It releases progesterone which thickens cervical mucus and prevents the build-up of the uterine lining

Question 24

What does the IUD stand for?

Answer 24

intrauterine device

Question 25

What is the IUD?

Answer 25

A small copper-containing device inserted into the uterus, which prevents the implantation of embryos

Question 26

What is a spermicide?

Answer 26

A chemical that kills or immobilises sperm cells - however they are not every effective, and work better when combined with barrier methods

Question 27

What is a barrier method of contraception?

Answer 27

A physical separation between the sperm and the egg

Question 28

What are 2 examples of barrier contraceptives?

Answer 28

• Condoms
• Diaphragms

Question 29

What are condoms?

Answer 29

a thin sheath worn on the penis or inside the vagina - protects against STIs but may tear or break

Question 30

What are diaphragms?

Answer 30

A thin cap placed over the cervix - prevent the entry of sperm

Question 31

What surgical methods of contraception are available?

Answer 31

sterilisation - in males, the sperm ducts are tied and in females the oviducts are tied

Question 32

What is abstinence?

Answer 32

The practise of not having sex, which also avoids pregnancy

Question 33

What is the rhythmn method?

Answer 33

When people abstain from having sex around the time of ovulation - however it is quite unreliable

Question 34

How do fertility drugs increase the chance of pregnancy?

Answer 34

Many fertility drugs contain FSH and LH

Question 35

What does IVF stand for?

Answer 35

In vitro fertilisation

Question 36

What is the process of in vitro fertilisation?

Answer 36

1. The mother is given FSH and LH , which stimulates maturation of eggs and ovulation
2. Eggs are fertilised using sperm in a laboratory and develop into embryos
3. 1 or 2 embryos are inserted into the mother’s womb

Question 37

What are the advantages of IVF?

Answer 37

• allows infertile couples to have children
• can store a woman’s eggs for later

Question 38

What are the disadvantages of IVF?

Answer 38

• it can be a very expensive process
• it has a low success rate - especially for older couples
• increases the chance of multiple pregnancies which is dangerous for mother and babies
• side effects of fertility drugs