3.How are red blood cells and nerve cells adapted to their job?
The small size of the red blood cells plus the biconcave shape (concavities present on either side) provide a large surface area which makes them very efficient in absorbing oxygen. The small size also enables the red blood cells to travel through very fine capillaries in the body where they have to travel in a single file. Read more:
RBCs have to go everywhere in the body, including the tiny capillaries. They are designed specifically for this. They have a very thin center which allows them to bend to squeeze through these tiny blood vessels. This is where sickle cell anemia is become a problem. The cells are misshappen and can cause blockages. Also the membrane of these cells is designed to allow oxygen to easily diffuse through.
A nerve cell is really long and is the longest cell in our body. As it's so long it can stretch between different parts of our body. It is an elongated cell that transmits information between different parts of our body. Each nerve cell has a cell body, containing the nucleus, from which trail processes called dendrites, responsible for receiving incoming signals. The brain controls many nerve cells. Read more:
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