Bio Hsc Notes (Except Parcs)
The Search for better health – notes on all parts except first hand pracs
• Discuss difficulties in defining the terms health and disease.
Health is defined as the complete physical, physiological, mental and social wellbeing of an organism. It is not merely the absence of disease. Disease can be defined as a state which prevents correct functioning or impairs bodily function. It is difficult to define these terms as they are very subjective and dynamic, i.e. they differ from person to person. Old age is an example of how definitions can be misleading because they suffer impaired body function yet they may not be diseased or sick.
• Outline how the function of genes, mitosis, cell differentiation and specialization can assist in the maintenance of health.
Genes – growth and healing is controlled by protein metabolism which is controlled by genes.
Mitosis – keeps cells at a healthy ratio and allows new cells to replace ones that can no longer function
Cell Differentiation and specialisation– without this there would be no specialized cells to maintain health e.g. lymphocyte production is increased during infection.
• Use available evidence to analyse the links between gene expression and maintenance and repair of body tissues.
Genes account for the maintenece and repair of body tissue. As DNA controls cell function and DNA is made up of genes, it can be said that genes control cell activity. In regards to repair, gene expression therefore controls this repair process. For example when a person is cut, genetic material controls the renewal process. Without this, organisms would not be able to repair themselves and maintain cell size etc. and an organism would thus be unhealthy.
• Distinguish between infectious and non-infectious diseases
Infectious diseases are caused by pathogens that can be transmitted from one organism to another.
Non infectious diseases can not be transmitted. They can be either environmental,
• Discuss difficulties in defining the terms health and disease.
Health is defined as the complete physical, physiological, mental and social wellbeing of an organism. It is not merely the absence of disease. Disease can be defined as a state which prevents correct functioning or impairs bodily function. It is difficult to define these terms as they are very subjective and dynamic, i.e. they differ from person to person. Old age is an example of how definitions can be misleading because they suffer impaired body function yet they may not be diseased or sick.
• Outline how the function of genes, mitosis, cell differentiation and specialization can assist in the maintenance of health.
Genes – growth and healing is controlled by protein metabolism which is controlled by genes.
Mitosis – keeps cells at a healthy ratio and allows new cells to replace ones that can no longer function
Cell Differentiation and specialisation– without this there would be no specialized cells to maintain health e.g. lymphocyte production is increased during infection.
• Use available evidence to analyse the links between gene expression and maintenance and repair of body tissues.
Genes account for the maintenece and repair of body tissue. As DNA controls cell function and DNA is made up of genes, it can be said that genes control cell activity. In regards to repair, gene expression therefore controls this repair process. For example when a person is cut, genetic material controls the renewal process. Without this, organisms would not be able to repair themselves and maintain cell size etc. and an organism would thus be unhealthy.
• Distinguish between infectious and non-infectious diseases
Infectious diseases are caused by pathogens that can be transmitted from one organism to another.
Non infectious diseases can not be transmitted. They can be either environmental,