Nucleus: Controls cells activities
Cell Membrane: Controls movement in and out
Cytoplasm: Where chemical reactions take place
Cell Wall: Strengthens/Supports the cell. (made out of Cellulose)
Mitochondria: Where most energy is released
Ribosomes: Site of protein synthesis
Your cells need many chemical reactions to happen at the right rates in the right places. Many of the chemical reactions would not normally happen at a sensible rate at body temperature.
That's why our bodies use enzymes. They are made of protein and as as catalysts to help the reactions.
Each enzyme is specific to a particular reaction, so your body has many thousands of them.
Each chemical process needs a whole set of enzymes. For example, they enzymes found in chloroplasts would be associated with photosynthesis.
We use enzymes in biological washing powders and liquids. They allow reactions to occur at low temperatures. This saves energy and prevents fabric from being damaged.
Sperm Cell - The midsection contains a lot of mitochondria to provide energy for the sperm.
Egg Cell - Contains a large amount of cytoplasm; an energy store.
Root hair cell - Has a large surface area to maximise the absorption of water.
Palisade Layer - Has lots of chloroplasts for photosynthesis in a leaf.