State that the kidneys excrete urea and excess water and ions
State that the kidneys excrete urea and excess water and ions
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State that the kidneys excrete urea and excess water and ions
State that carbon dioxide is excreted through the lungs
Explain how the spread of STIs is controlled
Describe the methods of transmission of HIV
State that HIV infection may lead to AIDS
State that human immunodeficiency virus (HIV) is a pathogen that causes an STI
Describe a sexually transmitted infection (STI) as an infection that is transmitted through sexual contact
Explain the role of hormones in controlling the menstrual cycle and pregnancy, limited to FSH, LH, progesterone and oestrogen
Describe the sites of production of oestrogen and progesterone in the menstrual cycle and in pregnancy
Describe the menstrual cycle in terms of changes in the ovaries and in the lining of the uterus