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a) The cell membrane is semi permeable- The pores that occur on the cell membrane allows the passage of the small size molecules but does not allow the passage of the large sized molecules.
Such a membrane is said to be selectively permeable or semi-permeable. In particular, when a cell is surrounded by a dilute sugar solution, the small sized water molecules will enter the cell but the larger sugar molecules will not pass through the cell membrane.
In contrast, the cell wall is permeable as it allows both sugar and water molecules to pass through it; it has larger pores. This property of selectively permeability enables the cell membrane to select what enters and leaves the cell.
b)The cell membrane is sensitive to changes in temperature and pH- Cell membranes are made up of protein. Proteins are adversely affected by extreme changes in temperature and pH.
Changes in temperature and pH will alter the structure of the cell membrane thereby hindering the normal functioning of the cell membrane. High temperature denatures (destroys) the proteins thereby impairing the functions of the cell membrane.
c)The cell membrane possesses electric charges- The cell membrane has both positive and negative charges. These charges affect the manner in which substances move in and out of the ells. The charges also enable the cell to detect changes in the environment.
simiyu kelly answered the question on September 15, 2017 at 11:34
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