unit 2

Question 1

What are the male gametes?

Answer 1

sperm cells

Question 2

What kind of fertility are males?

Answer 2

Continuous fertility

Question 3

What does continuous fertility mean?

Answer 3

Produce sperm cells continuously from puberty until death.

Question 4

where is sperm produced?

Answer 4

In the seminiferous tubules inside the testes.

Question 5

What are sperm cells surrounded by in the seminiferous tubule?

Answer 5

blood vessels and clusters of interstitial cells that produce the hormone testosterone.

Question 6

What are 3 important things that make up a sperm cell?

Answer 6

• nucleus
• mitochondria
• tail

Question 7

what happens during ejaculation?

Answer 7

Semen passes through the sperm duct and the urethra to be ejected into the female reproductive tract. Semen is a mixture of sperm and secretions from the seminal vesicles and prostate gland. Which maintain the mobility and viability of the sperm.

Question 8

How does the prostate gland contribute to sperm?

Answer 8

The prostate gland secretes a milky fluid containing enzymes that keep the fluid thin.

Question 9

How does seminal vesicles contribute to sperm?

Answer 9

The seminal vesicles secrete an alkaline, viscous fluid containing fructose and prostaglandins. Fructose is a respiratory substrate which provides energy for movement in the sperm tail. Prostaglandins cause the female reproductive tract to contract, helping sperm movement.

Question 10

What happens at the onset of puberty?

Answer 10

The pituitary gland is stimulated to produce FSH and ICSH by a releaser hormones from the hypothalamus.

Question 11

How do hormones reach their target organs?

Answer 11

Through the blood stream

Question 12

What is sperm production under the control of?

Answer 12

FSH (follicle stimulating hormone) and ICSG (interstitial cell stimulating hormone)

Question 13

What does FSH do in the hormonal control?

Answer 13

FSH acts on the seminiferous tubules to promote sperm production.

Question 14

What does ICSH do in the hormonal control?

Answer 14

ICSH acts on the interstitial cells of the testes, stimulating the production of testosterone.

Question 15

What does testosterone do in the hormonal control?

Answer 15

Testosterone is produced by the interstitial cells in the testes. It acts on the seminiferous tubules, stimulating sperm production and activates the prostate and seminal vesicles.

Question 16

what is overproduction of testosterone prevented by?

Answer 16

Negative feedback mechanism. When the testosterone level increases above normal, it inhibits secretion of FSH and ICSH from the pituitary. Testosterone production then stops until the level drops below normal, when the inhibitory effect is switched off and production begins again.

Question 17

What kind of fertility does the women have?

Answer 17

cyclical fertility

Question 18

What does cyclical fertility mean?

Answer 18

(eggs are only produced once a month) due to changes in hormone levels throughout the menstrual cycle. This continues from puberty to menopause.

Question 19

What does the menstrual cycle consist of?

Answer 19

cyclical changes in both the ovaries and the uterus.

Question 20

What happens in the follicular phase?

Answer 20

Under the influence of follicle stimulating hormone (FSH) from the pituitary gland, follicles begin to develop during the follicular phase. The follicular cells produce follicular fluid, which gathers within the follicle as it enlarge; and secretes oestrogen, which acts on the pituitary gland, stimulating the production of luteinising hormone (LH). Usually only one follicle matures fully to produce a Graafian follicle. Peak oestrogen level stimulates a LH surge. About 10-12 hours later, the graafian follicle ruptures (causing ovulation) on about 14 of the menstrual cycle, releasing the ovum.

Question 21

What happens in the Luteal stage?

Answer 21

The ovum now enters the ovum stage where, under the influence of LH, the corpus luteum develops from remaining cells of the ruptured follicle. The corpus luteum produces progesterone and oestrogen, which have a negative-feedback effect on the pituitary gland, inhibiting the release of FSH and preventing the development of any more follicles. If not pregnancy occurs, LH, progesterone and oestrogen levels will decrease and the corpus luteum will degenerate, allowing the development of follicles to begin again in the next cycle. If there is a pregnancy, the corpus luteum continues to function until the placenta is large enough to take over hormone production.

Question 22

During the menstrual cycle, what changes occur?

Answer 22

menstruation - low levels of oestrogen and progesterone cause the lining layer of the uterus (endometrium) to be shed. The menstrual flow consists of a mixture of endometrial cells, mucus, blood and tissue fluid.

follicular phase- increasing oestrogen production from the ovarian follicles stimulates repair of the endometrium. The endometrium becomes thicker and develops a good blood supply. Oestrogen also makes the cervial mucus less viscous, allowing sperm to pass through more easily.

Luteal phase - After ovulation, the endrometrium continues to thicken under the influence of progesterone from the corpus luteum. This is accompanied by further development of the endometrial blood vessels and endometrial glands, preparing the uterus for implantation of the blastocyst. should fertilisation take place. If there is no fertilistation, the drop in progesterone level that results from degeneration of the corpus luteum causes the uterus to enter the next menstrual phase. If fertilistation does occur, the endometrium will be maintained.