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12 Cards in this Set
- Front
- Back
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What is the function the testes, scrotum, prostate gland, sperm duct, urethra and penis? |
Testes- to produce sperm Urethra- To carry sperm out of the body (or urine) Prostate glands- To add fluid to sperm Scrotum- To protect the testes Sperm duct- To carry sperm from the testes |
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What is the function of the cervix, urethra (in women), uterus, vagina, ovaries and oviducts? |
Cervix- A ring of muscle at the lower end of the uterus which leads to the vagina Urethra- Above the vagina; where urine passes out Ovaries: Female sex organs that produce female gametes ( egg cells). Also makes female hormones oestrogen and progesterone. Oviducts: The vessel where the egg travels to the uterus Vagina: Sometimes known as the 'birth canal'; babies pass through here during birth Uterus: The uterus nurtures the fertilised ovum that develops into a fetus and hold it till the baby is mature enough for birth. |
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What is the difference in size, number and mobility between the female and male gametes? |
Size: The male gamete (sperm) is very small, and the egg cell is much larger and can be seen by the naked eye Number: Millions of sperm cells are constantly produced after puberty and often through life, which egg cells are only produced once a month after puberty until menopause, and not during pregnancy or when taking the contraceptive pill Mobility: Sperms swim using their tail that lashes side to side, eggs cannot move themselves and move along the oviducts by beating cilia and peristalsis |
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Describe the menstrual cycle in terms of changes in the ovaries and uterus |
The menstrual cycle is a monthly cycle which a woman's uterus prepares for a fertilised egg to settle and grow into a baby. A cycle is normally 28 days. On the first day of the cycle, the uterus lining breaks down, and will be the first day of a woman's menstruation (period). After menstruation, the lining of the uterus builds up again in preparation for a fertilised egg, and around day 14 an egg is released from a follicle in the ovaries (this is ovulation). If the egg is fertilised it will embed itself onto the uterus lining, and the lining is maintained and the woman becomes pregnant. If not, the lining breaks down and the woman starts her period again. |
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Describe fertilisation in terms of the joining of the nuclei of the female and male gametes. |
Fertilisation is when the sperm membrane fuses with the egg membrane after successful penetration, and the nucleus of the sperm enters the egg's cytoplasm and fuses with its own nucleus. The zygote nucleus with two sets of chromosomes is formed, and a membrane is immediately formed around the zygote to stop other sperm cells from entry. |
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Outline the early development of the zygote |
In the early implantation stage of the zygote, the zygote will first begin to divide after fertilisation. The embryo is a hollow ball of cells after a few hours, and is moved down the oviduct to the uterus. The embryo then embeds into the uterus lining which has thicken in preparation, and the embryo obtains food and oxygen from blood vessels by diffusion, which carbon dioxide and chemical waste diffused in the opposite direction. |
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Indicate the functions of the amniotic sac and the amniotic fluid. |
During pregnancy, the fetus becomes surrounded by a membrane called the amniotic sac which contains amniotic fluid. This fluid supports the fetus and protects it from damage. |
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Describe the function of the placenta and umbilical cord |
The placenta is formed from embryonic tissue, and is disk-shaped and has many villi surrounded by blood spaces in the uterus. The placenta supplies nutrients and oxygen to the fetus, while removing carbon dioxide and other waste products. The umbilical cord joins the fetus to the placenta, and contains and artery and a vein that carries fetal blood back and forth to the placenta. |
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Describe the advantages and disadvantages of breast-feeding compared with bottle feeding using formula milk. |
Advantages: Breastmilk had advantages over formula milk since it contains antibodies which pass to the baby and gives it passive immunity to diseases the mother has had recently. It also enables a close bond to form between the mother and the child. Children who are breastfed are less likely to get childhood diseases such as childhood cancers, and mothers who breastfeed are less likely to develop cancers of breast, womb and ovaries. Disadvantages: Formula milk is much more easy to use in public settings where it might be indiscreet to breastfeed. It is also the only option for women who do not have enough breast milk. |
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Describe the methods of transmission of HIV |
HIV can be transmitted by: - In the blood and semen - i.e. during sex - Can be passed by unsterilised needles with infected blood - Placenta to fetus - Mother to baby's blood during birth - Breastmilk - Blood transfusions |
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Outline how HIV affects the immune system in a person with HIV/ AIDS. |
HIV attacks and destroys T lymphocytes, which coordinate the immune system. This means fewer antibodies are produced every time there is an infection, and a weakened immune system can lead to an easier death. Early symptoms of AIDS are like the flu, and eventually progresses into symptoms such as cancer and brain damage. |
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How do you prevent HIV/AIDS? |
- Use condoms during sex - Free needle exchange scheme to prevent shared needles amongst drug users - Careful screening of blood used for transfusions |
