<Li> Physical agents such as heat or radiation can damage a cell by literally cooking or coagulating their contents . </Li> <Li> Impaired nutrient supply, such as lack of oxygen or glucose, or impaired production of adenosine triphosphate (ATP) may deprive the cell of essential materials needed to survive . </Li> <P> The most notable components of the cell that are targets of cell damage are the DNA and the cell membrane . </P> <Ul> <Li> DNA damage: In human cells, both normal metabolic activities and environmental factors such as ultraviolet light and other radiations can cause DNA damage, resulting in as many as one million individual molecular lesions per cell per day . </Li> <Li> Membrane damage: damage to the cell membrane disturbs the state of cell electrolytes, e.g. calcium, which when constantly increased, induces apoptosis . </Li> </Ul>

Explain how the abnormal function of cellular organelles can cause medical conditions