2.5 Human Reproduction

Question 1

What happens during puberty?

Answer 1

During puberty, reproductive hormones cause secondary sex characteristics to develop

Question 2

Define primary sexual characteristics

Answer 2

Primary sexual characteristics are the ones you are born with

Question 3

What are the primary sexual characteristics for boys and girls

Answer 3

• Testes for boys
• Ovaries for girls

Question 4

What is the main male reproductive hormone

Answer 4

The main male reproductive hormone is testosterone which is produced by the testes and stimulates sperm production

Question 5

Describe the main female reproductive hormone

Answer 5

The main female reproductive hormone is oestrogen, which is produced by the ovaries

Question 6

What role does oestrogen play before the menstrual cycle?

Answer 6

Oestrogen causes the development of secondary sex characteristics such as growth spurts, developed pubic hair and developed breasts

Question 7

What is ovulation?

Answer 7

Ovulation occurs at puberty, and is when eggs begin to mature and one is released every 28 days

Question 8

What is ovulation part of?

Answer 8

Ovulation is part of the menstrual cycle

Question 9

What happens during the menstrual cycle?

Answer 9

• The eggs begin to mature and one is released every 28 days (ovulation)
• In preparation for ovulation, the uterus produces a thickened lining ready for pregnancy
• The egg then makes its way down the uterus
• If sperm is present, the egg becomes fertilised and implants itself into the uterus wall and develops into a baby
• If the egg does not become fertislised, both the egg and uterus lining are shed and released, which is known as a period

Question 10

What are the 4 key hormones in the menstrual cycle?

Answer 10

• Follicle Stimulating Hormone (FSH)
• Luteinising Hormone (LH)
• Oestrogen
• Progesterone

Question 11

What is the role of FSH (Follicle Stimulating Hormone) in the menstrual cycle?

Answer 11

FSH causes the eggs in the ovary to mature

Question 12

What is the role of LH (Luteinising Hormone) in the menstrual cycle?

Answer 12

LH stimulates the release of the egg at ovulation

Question 13

What is the role of Oestrogen and Progesterone in the menstrual cycle?

Answer 13

Oestrogen and Progesterone stimulate the build-up and maintain the lining of the uterus for the egg

Question 14

How do the hormones interact in the menstrual cycle?

Answer 14

• FSH is released by the pituitary gland. It travels through the blood to the ovaries, where it causes an egg to mature
• At the same time, FSH also triggers the ovaries to make oestrogen, which causes the lining of the uterus to become thick
• High levels of oestrogen inhibits (prevents) the production of more FSH and stimulates the release of LH
• LH triggers ovulation - the releasing of a mature egg
• Once the ovary has released the egg, it produces the hormone progesterone, which inhibits both FSH and LH, to prevent any more eggs from maturing or being released
• It also maintains the lining of the uterus in the 2nd half of the cycle, in case an egg becomes fertilised
• If fertilisation does not occur, the levels of progesterone fall and the uterus lining and egg are released (known as period)

Question 15

Describe the order in which the hromones are released

Answer 15

• First FSH is released
• Then Oestrogen
• Then LH
• Then Progesterone

Question 16

What is contraception?

Answer 16

Contraception is preventing fertilisation

Question 17

List and describe the hormonal methods of contraception

Answer 17

• Oral contraceptives (such as pills) that contain hormones to inhibit FSH production so that no eggs mature
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