Igcse B8.3

Front 1

describe the menstrual cycle

Back 1

- Menstruation uterus lining is shed
- Ovulation ovum released from ovary
- ovum dies if not fertilised
- uterus lining continues to thicken

Front 2

Describe fertilisation

Back 2

- the head of the sperm (the male nucleus) moves towards the nucleus of the ovum and the two fuse (join together).

Front 3

Describe the methods of transmission of human immunodeficiency virus (HIV)

Back 3

- unprotected sex with an infected person
- contact with an infected person's blood
- from mother to child, during pregnancy of childbirth
- sharing syringes while injecting drugs

Front 4

Describes the ways in which HIV/AIDS can be prevented from spreading

Back 4

- education programmes to prevent infections
- provision of antibiotics
- have a medical check if any symptoms occur
- use a condom for barrier protection
- know the sexual history of their partners

Front 5

Describe the function of the placenta

Back 5

- exchange of soluble materials such as foods, wastes and oxygen between mother and fetus physical attachment of the fetus to the wall of the uterus
- protection of fetus from mother's immune system
- protection against dangerous fluctuations in mother's blood pressure

Front 6

Describe the function of the umbilical cord

Back 6

- contains blood vessels which carry materials for exchange between mother and fetus.
- The cord connects the fetus to the placenta.

Front 7

Describe the advantages of breast-feeding compared with bottle-feeding using formula milk

Back 7

- human milk is low in bacteria and contains antimicrobial factors so that breast-fed infants suffer fewer infections
- human milk is low-cost
- is delivered at body temperature
- requires no preparation and breast-feeding encourages a social bond between mother and infant

Front 8

Describe the disadvantages of breast-feeding compared with bottle-feeding using formula milk

Back 8

- suckling may have a contraceptive effect
- bottle-feeding infants in the developing countries may have 10-15 times greater mortality than breast-fed babies.

Front 9

Outline how HIV affects the immune system in a person with HIV/AIDS

Back 9

- immune system begins to fail
- fungal infection of the lungs

Front 10

Indicate the functions of the amniotic sac

Back 10

- the membrane that encloses the amniotic fluid
- this is ruptured just before birth

Front 11

Indicate the functions of the amniotic fluid

Back 11

- protects the fetus against
- mechanical shcok
- drying out
- temperature fluctuations