Cholesterol is found in the cell membranes of animal cells, responsible for regulation of fluidity of cell membrane.

Found in the cell membrane to control fluidity of the membrane.

Basically cholesterol seen in the your liver

There are two types of cholesterol:blood (serum) and dietary cholesterol. Blood (serum) cholesterol circulates in the bloodstream. While every cell can make cholesterol, the liver produces most of it. When the body makes too much, this increases the risk for heart disease, including heart attack and stroke.

The body of an adult can make all the cholesterol it needs, but most people also get it from foods. Unlike adults, children under age two do not produce enough cholesterol; therefore, their food must supply part of it.

Plants do not produce cholesterol, even if they contain fat. Dietary cholesterol only comes from foods of animal origin. Common sources are eggs, meats, poultry, fish, dairy products and animal fats, such as butter or lard.

Well this is quite a broad question.

However, related to your A levels you only really need to know that you have cholesterol in your plasma membranes of all your cells, which helps to regulate their fluidity!

Cholesterol is found in the liver