reproduction in humans

Question 1

testes

Answer 1

where sperm and testosterone is produced

Question 2

scrotum

Answer 2

holds testicles

Question 3

sperm duct

Answer 3

carries sperm from testicles to urethra

Question 4

prostrate gland

Answer 4

makes seminal fluid

Question 5

urethra

Answer 5

carries semen from the sperm duct to the tip of the penis

Question 6

ovary

Answer 6

produces progesterone and oestrogen where egg cells develop

Question 7

oviduct fallopian tube

Answer 7

carries egg to the uterus, fertilisation occurs here

Question 8

uterus

Answer 8

where the fetus developes

Question 9

cervix

Answer 9

strong rigid muscle, keep developing foetus in a place

Question 10

features of a sperm cell

Answer 10

flagellum - helps cell move locomotion
nucleus - contains DNA
acrosome - contains enzymes that help the sperm cell get through the egg’s protective coat
mitochondria - provides energy from respiration so the sperm can move

Question 11

features of an egg cell

Answer 11

cytoplasm - contains nutrients for the growth of early embryo
cell membrane - changes after fertilisation so that no more sperm can enter

Question 12

fertilisation process

Answer 12

sperm touches egg membrame and acrosome releases enzymes, the enzymes break down the egg’sjelly coat, protein on sperm head bind to egg receptors, sperm nucleus enters egg cytoplasm, After fertilisation in the oviduct, the zygote travels towards the uterus
This takes about 3 days, during which time the zygote will divide several times to form a ball of cells known as an embryo
In the uterus, the embryo embeds itself in the thick lining (implantation) and continues to grow and develop

Question 13

umbilical cord

Answer 13

oxygen and nutrients form mother to child and waste products and urea from foetus to mother

Question 14

amnitoic sac

Answer 14

membrane which holds the amniotic fluid

Question 15

amniotic fluid

Answer 15

keeps foetus moist, lubricates vagina, reduces temperature fluctuation absorbs shock

Question 16

placenta

Answer 16

The placenta acts as a barrier to prevent toxins and pathogens getting into the fetus’s blood
addaptations :a large surface area and a thin wall for efficient diffusion

Question 17

exhange in placenta from mother to foetus

Answer 17

oxygen, glucose

Question 18

exhange in placenta from foetus to mother

Answer 18

co2, water, urea

Question 19

toxins that can pass through the plancenta barrier

Answer 19

nicotine, hiv, rubella, alchool, drugs

Question 20

stages of birth

Answer 20

Amniotic sac breaks
Muscles in the uterus wall contract
Cervix dilates (gets wider)
Baby passes out through the vagina
Umbilical cord is tied and cut
Afterbirth is delivered

Question 21

breast feeding advantages and dis

Answer 21

has antibodies, cheap, mother child bond, no additives

dis - may be painful, time consuming

Question 22

antenatal care

Answer 22

diet - more protein (foetus growth), clacium for bones and teeth, iron, vitamin d and c blood vessels and bones

Question 23

chemical contraception

Answer 23

IUD - releases sex hormones which thicken the mucus produced in the cervix, making it difficult for sperm to swim into the uterus
it also thins the lining of the uterus, making it more difficult for a fertilised egg to implant
Contraceptive pill - raising the levels of progesterone and oestrogen, the uterus lining is maintained and the development of another egg cell is prevented
implant, injection

Question 24

Artificial Insemination (AI)

Answer 24

If the male is not producing healthy sperm, donor sperm can be used

Question 25

In Vitro Fertilisation (IVF)

Answer 25

The eggs are then inseminated in a petri dish using sperm from the male and, once embryos have formed, they are placed back into the uterus of the female

Question 26

How HIV Affects the Immune System

Answer 26

It then infects a certain type of lymphocyte and uses the cells’ machinery to multiply
This reduces the number of lymphocytes of the immune system, and also the number of antibodies that can be made
This decreases the body’s ability to fight off infections, eventually leading to AIDS