6. Why do you think it is necessary to rinse off the excess stain from the specimen before looking at it under the microscope?
7. The cover-slip should be applied at an angle, what is the reason for this? 7.3 Cell structure and function
All cells have the same basic structure but different types of cells have special features that are suited to the functions that they carry out.
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Sperm cell Tail for swimming. Lots of mitochondria to give the energy required to swim to the egg.
Haemoglobin The chemical that allows red blood cells to carry oxygen to other cells in the body.
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Red blood cells Contain a chemical called haemoglobin which can bond to oxygen. Red blood cells carry oxygen around the body. Their shape allows them to bend to fit through small blood vessels.
Do not contain a nucleus.
Muscle cells Lots of mitochondria for energy. Can contract and relax to enable movement.
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Light-sensitive cells in the eye A layer at the back of the eye called the retina contains special cells that can detect black and white and coloured light. This allows us to see.
