Biology Revision

The search for better health

Discuss the difficulties of defining the terms 'health' and 'diseases':

Health is hard to define because it incorporates many things and some can be very subjective. Such as, biological, psychological and social well-being. Disease is similarly difficult to define because it is a state of impairment functioning or poor health. It depends on an individual's normal level of functioning and on what they expect their quality of life to be.

Outline how the function of genes, mitosis, cell differentiation and specialisation assist in the maintenance of health:

The function of genes is to ensure that the correct proteins are produced in a cell to enable all cellular processes continue. Mitosis enables the genetic material to be copied correctly when new cells are formed. Different types of cells become specialised for different functions within a multicellular organism.

Distinguish between infectious and non-infectious disease: An Infectious diseases can pass to another organism to another, where-as a non-infectious disease cannot.

Person washing his hands

English: Spongiform Change in CJD

USNA tour of U.S. Army Medical Research Institute ...

Explain why cleanliness in food, water and personal hygiene practices assist in control of disease:

Control measures such as cleanliness can stop the spread of infectious diseases, particularly if we know how a disease is transmitted. General hygiene and cleanliness are important in reducing the transmission of infectious diseases. Prevents the growth of disease thus reducing the likelihood of somebody contracting the disease.

Identify the conditions under which an organism is described as a pathogen: Organisms are called pathogens when they cause disease.

Describe the role of Pasteur in identifying the causes of disease: Pasteur discovered that most infectious diseases are caused by microorganisms, or germs. This became known as the germ theory of disease. This also destroyed the theory of spontaneous generation.

Outline Koch's postulates and explain how they can be used to identify the causative organism...