2.2

Question 1

What is puberty?

Answer 1

the physiological transition period as a child becomes an adult. During this period there are a number of physiological changes.

Question 2

How does the brain stimulate the onset of puberty?

Answer 2

the hypothalamus secretes a releaser hormone which acts on the pituitary gland. The pituitary gland is stimulatd to release hormones.

Question 3

What hormones guide puberty in males?

Answer 3

Follicle stimulating hormone (FSH) and Interstitial cell stimulating hormone (ICSH)

Question 4

What hormones guide puberty in females?

Answer 4

Follicle stimulating hormone (FSH) and lutenising hormone (LH)

Question 5

What is the role of FSH in males?

Answer 5

stimulates sperm production in the seminiferous tubules.

Question 6

What is the role of ISCH in males?

Answer 6

stimulates the release of testosterone by the interstitial cells.

Question 7

What is the role of testosterone in sperm production?

Answer 7

stimulates sperm production in the seminiferous tubules and stimulates the production of seminal fluid by the prostate gland and seminal vescicles.

Question 8

Break down the negative feedback system controlling sperm production

Answer 8

an increase in blood testosterone concentration inhibits FSH and ISCH secretion by the pituitary gland. The decreased FSH and ISCH causes a decrease in testosterone production. Low testosterone level causes an increase in FSH and ISCH secretion, which in turn increase testosterone production.

Question 9

What is the role of the menstrual cycle?

Answer 9

to prepare the body for a possible pregnancy

Question 10

What is the endometrium and what is its role?

Answer 10

the lining of the uterus that develops in thickness and vascularisation over the course of the menstrual cycle. It develops to prepare for the potential embedding of a fertilised zygote. If this happens the endometrium has a major role in aiding the maturation of the devloping embryo.

Question 11

What is menstruation?

Answer 11

the discharge of the uterine lining (endometrium) through the vagina. This occurs each month if an egg has not been fertilised.

Question 12

Approximately, how long does the menstrual cycle last and when is considered day 1?

Answer 12

approximately 28 days and it begins on the first day of menstruation.

Question 13

When is the follicular phase of the menstrual cycle?

Answer 13

occurs from day , the beginning of the menstruation, to ovulation.

Question 14

Breakdown what happens during the follicular phase? (4 stages)

Answer 14

Stage 1 - FSH stimulates the development of one follicle in the ovary.
Stage 2 - the follicle produces oestrogen which causes the proliferation of the endometrium and thinning of cervical mucus.
Stage 3 - the oestrogen levels rise in the blood and peak levels stimunlate the pituitary gland to secrete a surge of LH.
Stage 4 - this surge in LH triggers the release of the ovum from the ovary to travel to the oviduct. This is called ovulation.

Question 15

How does oestrogen production affect the endometrium?

Answer 15

stimulates proliferation of the endometrium

Question 16

How else does oestrogen prepare for fertilisation?

Answer 16

causes the thinning of the cervical mucus, allowing the mucus to be easily penetrated by sperm.

Question 17

When is the luteal phase in the menstrual cycle?

Answer 17

from ovulation until the first day of menstruation

Question 18

Break down what happens in the luteal phase (4 stages)

Answer 18

Stage 1 - the ovum is released into the oviduct at ovulation.
Stage 2 - the follicle changes to become the corpus luteum, which secretes progesterone, which maintains the endometrium.
Stage 3 - oestrogen and progesterone inhibit FSH and LH.
Stage 4 - if fertilisation does not occur, the corpus luteum breaks down and progesterone is no longer secreted. This causes a breakdown of the endometrium, leading to menstruation.

Question 19

What affect does progesterone have on the endometrium?

Answer 19

progesterone stimulates vascularisation and further development of the endometrium.

Question 20

Where is progesterone produced?

Answer 20

by the corpus luteum in the ovary

Question 21

Describe what happens at the end of the menstrual cycle if the egg is not fertilised

Answer 21

if the egg is not fertilised, the corpus luteum breaks down and stops producing progesterone. Therefore, the endometrium is no longer maintained and menstruation occurs.

Question 22

Describe what happens at the end of the menstrual cycle if the egg is fertilised

Answer 22

if the egg is fertilised and the woman becomes pregnant, the placenta produces progesterone and the endometrium is maintained