Describe one biological factor and explain how it causes a variation in the health status between those living within and outside Australia's major cities.

1. Micro-organism

Explanation:

Micro organism are disease causing agents,which cannot be seen with the human naked eyes. The use of of magnification lens or microscope goes a long way in making them visible.

People living within the Australia's major city are exposed to a lot of disease causing organism than those who stays outside the city.

A city is been define as a collection of heterogeneous set of people,and a key criteria is it's population.

Daily business activities within the city surpasses that which happens outside the city.The handling of door knobs,elevators buttons ,stair rails and other common objects which can be touched by humans,there by making the transmission and inhabitation of fungi,viruses and bacterial infection more likely within the major cities.

the skin color

Explanation:

One of the variations that take place is the skin color of people. The skin color is usually affected by factors such as the environment that a person lives in. In fact, in biology, the phenotype of a person is both a work of the genotype and environmental factors. One of the environmental factors to the skin color might be the melanin amount in the skin. For example, people who are out for most of the times have a darker skin. For the Caucasian person, the skin becomes more tanned, that is more rich in color. Exposing the skin to the sun causes a skin and the body to develop and synthesize more melanin. This is an example of genetics and the effect on the skin color.