1. What is a healthy organism?

Discuss the difficulties of defining the terms 'health' and disease 'Disease' is a very broad term: Any condition that disturbs the normal functioning of the body. Health varies on a daily basis and is not just the absence of disease. It varies with age and susceptibility to disease. It is the complete state of mental physical and social wellbeing. The problems with defining health and disease is:   -someone can be healthy but also with disease at the same time   -they are terms used every day and have different meanings to the scientific definitons.

Use available evidence to analyse the links between gene expression and maintenance and repair of body tissuesGene expression: the transfer of information a gene to produce a protein or RNA. If the code is incorrect, the proteins made from the incorrect code will not be suitable for their function.e.g. if you cut yourself, the code contained in all your cells is used to form the new tissue to repair the damage from the cut. However if the code is incorrect, this repair will not happen as it should.

Outline how the function of genes, mitosis, cell differentiation and specialisation assist in the maintenance of healthGene expression is essential for the maintenance of health.Genes: -are the units of inheritance-control the process of protein synthesis-assist maintaining health by regulating the cell cycle and limiting the growth and reproduction of cells -provide the code for each proteinMitosis: -cell division that makes two identical cells-for growth and development-replaces millions of cells that die each dayCell differentiation:-the process undergone by the cells past the stage of differentiation-each cell has the genetic information necessary to produce all types of cells-cells normally differentiate to become specialised-undifferentiated cells for tumours 

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