Human Reproduction

Question 1

What happens days 1-5 of the menstruales cycle?

Answer 1

First day the lining of the uterus is shed and then FHS is released from the pituitary gland stimulating the growth of a new egg cell surrounded by a cluster of cells called a follicle

Question 2

What happens days 5-14

Answer 2

The follicle cells produce oestrogen which causes the lining of the uterus to build up again. Around day 14 ovulation happens (where a mature egg is released) and LH is released.

Question 3

Where is FSH released from and what is its role?

Answer 3

FSH is released from the pituitary gland and causes an egg to mature in an ovary and stimulates the ovaries to release oestrogen

Question 4

Where is oestrogen released from and what is its role?

Answer 4

Released from the ovaries and it stops FSH being produced (so that only one egg matures in a cycle). Repairs and thickens the uterus lining. Stimulates the pituitary gland to release LH.

Question 5

Where is LH released from and what is its role?

Answer 5

It is released from the pituitary gland and triggers ovulation (the release of a mature egg)

Question 6

Where is progesterone released from and what is its role?

Answer 6

It is released from the ovaries and it maintains the lining of the uterus during the middle part of the menstrual cycle and during pregnancy.

Question 7

What happens if fertilisation does not occur in the oviduct/fallopian tube?

Answer 7

The egg travels down the oviduct and is shed with the uterus. (The egg travels down the oviduct for 14 days and the oestrogen and progesterone levels fall in the last 2 days)

Question 8

What is implantation?

Answer 8

When the embryo embeds itself into the uterus lining

Question 9

What does the zygote undergo to become the embryo?

Answer 9

Mitosis

Question 10

How long is the average menstrual cycle

Answer 10

28 days

Question 11

How does the amniotic fluid protect a developing embryo and foetus?

Answer 11

It acts as a ‘shock absorber’ to protect it from bumps to the mothers body and provides a stable environment by regulating temperature

Question 12

Where do substances diffuse across from the mothers blood and the baby’s blood?

Answer 12

Th intervillous space

Question 13

How does the intervillous space protect the baby?

Answer 13

It can help stop harmful pathogens and some viruses from getting into the babies blood stream

Question 14

What is transferred through the umbilical cord?

Answer 14

To the baby: small soluble nutrients (glucose, other sugars, amino acids, fatty acids and glycerol) and oxygen (as it can not do gas exchange by itself) antibodies are also transferred across (as they are very small) to provide immunity
To the mother: carbon dioxide and urea

Question 15

How is the placenta adapted for exchange?

Answer 15

The lining is folded and has villi to increase surface area. It also has a big blood supply.

Question 16

What blood vessels are in the umbilical cord?

Answer 16

Veins and arteries

Question 17

What is the urethra?

Answer 17

the tube inside the penis that can carry urine or semen. A ring of muscle ensures that urine and semen do not get mixed up.

Question 18

What happens in the sperm duct and sex glands?

Answer 18

The sperm pass through the sperm ducts, and mix with fluids produced by glands. The fluids provide the sperm cells with nutrients. The mixture is semen

Question 19

What are the functions of the testes?

Answer 19

To produce sperm

To make the hormone testosterone

Question 20

What do the two ovaries contain?

Answer 20

Ova (eggs) ovum (egg)

Question 21

How do the eggs get from the ovary to the uterus?

Answer 21

Each ovary is connected to the uterus by an oviduct (fallopian tube). The oviduct is lined with ciliated cells. Every month, an ovum (egg) develops and becomes mature, and is released from an ovary. The cilia waft the ovum along inside the oviduct and into the uterus.

Question 22

What is the uterus and the cervix

Answer 22

The uterus is a muscular bag with a soft lining. It is where a baby develops until its birth. The cervix is a ring of muscle at the lower end of the uterus. It keeps the baby in place while the woman is pregnant.

Question 23

What is the vagina and cervix

Answer 23

The vagina is a muscular tube that leads from the cervix to the outside of the woman’s body. The opening to the vagina has folds of skin called labia that meet to form a vulva.
The urethra also opens into the vulva, but it is separate from the vagina. It passes urine out of the body from the bladder.

Question 24

What are the functions of a penis

Answer 24

• to pass urine out of the body from the bladder

- to pass semen into a woman