B15.4 - Sexual reproduction in humans

Question 1

What is the function of the testes? [1]

Answer 1

produces sperm

Question 2

What is the function of the scrotum? [2]

Answer 2

• holds the testes outside the body
• at the ideal temperature for the formation of sperm

Question 3

What is the function of the sperm ducts? [1]

Answer 3

muscular tube that carries sperm from the testis to the urethra

Question 4

What is the function of the prostate gland? [1]

Answer 4

gland that produces the liquid that gets added to the sperm to make semen

Question 5

What is the function of the urethra? [1]

Answer 5

tube which carries sperm through the penis during ejaculation

Question 6

What is the function of the penis? [2]

Answer 6

• swells when filled with blood
• for introducing sperm into the vagina of the female

Question 7

What is the function of the ovaries? [2]

Answer 7

• organ that produces the eggs
• and the sex hormones oestrogen and progesterone

Question 8

What is the function of the oviducts? [2]

Answer 8

• muscular tube that carries the egg from the ovary to the uterus
• fertilisation happens here

Question 9

What is the function of the uterus? [1]

Answer 9

organ where the embryo grows

Question 10

What is the function of the cervix? [2]

Answer 10

• ring of muscle at the neck of the uterus
• holds the baby in place during pregnancy

Question 11

What is the function of the vagina? [3]

Answer 11

• muscular tube connecting the uterus to the outside
• penis is inserted here during intercourse
• menstrual blood and the baby both leave the body this way

Question 12

What is the function of the uterus lining? [2]

Answer 12

• fertilised egg implants in to this
• if not pregnant - this is shed each month as a period

Question 13

What is fertilisation? [2]

Answer 13

the fusion of the nuclei from the male and female gametes

Question 14

What are the effects of oestrogen? [4]

Answer 14

• breasts develop
• body hair grows
• menstrual cycle begins
• hips get wider

Question 15

What are the effects of testosterone? [5]

Answer 15

• growth of penis and testes
• growth of facial and body hair
• muscles develop
• voice breaks
• testes start to produce sperm

Question 16

What is oestrogen? [2]

Answer 16

• sex hormone
• in GIRLS

Question 17

What is testosterone? [2]

Answer 17

• sex hormone
• in BOYS

Question 18

What are changes that occur to both boys and girls during puberty? [4]

Answer 18

• growth of sexual organs
• growth of body hair
• more interest in sex
• increased mood swings

Question 19

What is ovulation? [2]

Answer 19

• on the 14th day
• the egg is released

Question 20

What happens to the lining of the uterus each month? [1]

Answer 20

it thickens to prepare for a fertilised egg

Question 21

What happens to the egg at the same time the uterus lining thickens? [1]

Answer 21

the egg starts to mature in one of the ovaries

Question 22

What happens to the uterus lining after ovulation if the egg is fertilised? [2]

Answer 22

• egg may implant in the uterus lining
• where it is protected and receives nutrients and oxygen from the mother

Question 23

What happens if the egg is not fertilised? [2]

Answer 23

• the uterus lining breaks down
• both the egg and the lining are removed from the body during menstruation

Question 24

What is menstruation? [2]

Answer 24

the shedding of the uterus lining and egg when the egg is not fertilised

Question 25

What are the hormones involved in the menstrual cycle? [2]

Answer 25

- oestrogen - progesterone

Question 26

What is oestrogen during the menstrual cycle? [2]

Answer 26

- repairs/builds up the lining - secreted from the ovary

Question 27

What is progesterone during the menstrual cycle? [2]

Answer 27

- maintains the uterus lining - secreted from the ovary

Question 28

What are the adaptations of a sperm cell and their description? [6]

Answer 28

- flagellum = allows the sperm to swim towards the egg - contains many mitochondria = to provide energy for the movement of the flagellum - presence of enzymes = contains enzymes in the head to digest a route into the egg for fertilisation

Question 29

What are the adaptations of an egg cell and their description? [4]

Answer 29

- cytoplasm contains a store of energy = provides energy for mitosis in the developing zygote - jelly-coat changes at fertilisation to prevent more than one sperm from entering

Question 30

What is the size of a sperm and egg cell? [2]

Answer 30

- sperm: very small (0.045mm) - egg: large (0.15mm)

Question 31

What is the structure of a sperm and egg cell? [4]

Answer 31

- sperm: head region, flagellum, mid section containing mitochondria - egg: round cell covered in a jelly-coating and lots of cytoplasm

Question 32

What is the motility in a sperm and egg cell? [2]

Answer 32

- sperm: capable of locomotion - egg: not capable of locomotion