What are antagonistic muscles?
They are pairs of muscles which act on a joint. One muscle contracts as the other relaxes.
Describe the differences between air you breathe in and air you breathe out.
Air breathed in has more oxygen than the air you breathe out. The air you breathe out has more carbon dioxide than the air you breathe in.
Why do the lungs have millions of alveoli?
They give a large surface area so diffusion can happen quickly.
What surrounds the alveoli?
Blood vessels (capillaries).
What is puberty?
Puberty is the body preparing for reproduction.
What is menstruation?
Menstruation is when the lining of the uterus is shed once a month.
How long does a menstrual cycle take?
Approximately 28 days.
What is the role of the ovaries?
To produce eggs and hormones.
What is pollination?
When the pollen is transferred from an anther to a stigma and the male and female gametes fuse together.
