The Digestive System

Digestion is the breaking down of chemicals in the body to a form that can be absorbed and used. Digestion beings, in mammals, with the saliva in the mouth.

The Mouth

• This is the buccal cavity in a human and is where mechanical digestion and mastication (chewing) takes place. ...See More

Respiration

Respiration is a set of metabolic reations and processes that take place with in the cells of organisms. It converts biochemical energy into adenosine triphosphate (ATP).

ATP (Adenosine triphosphate)

• ATP is the main energy storage and transfer molecule in the cell. It's a nucleic acid similar to RNA. ...See More

The Immune System

Immunity can be defined as the capacity to recognise the intrusion of material foreign to the body and to moblise cells and cell products to remove that sort of foreign material with great speed and effectiveness. ...See More

Microbiology

Prokaryotes can be identified in three ways, judging their shape, whether they are gram-positive or negative and the way they move.

There are also differences other than shape, these include whether the bacteria is gram-positive or gram-negative. Gram-positive bacteria turn violet in colour when gram stained, whereas gram-negative absorb the red counter-stain this is due to the size of each their peptidoglycan. ...See More

The Atmosphere

The Earth and its atmosphere are one interconnected system which is controlled by the sun. Distinctive climatic regions are the result of atmospheric processes that operate within a global system. The basic force causing atmospheric motion is the variation in temperature between equatorial regions and the poles. ...See More