Complete Table 6.1 by filling in the missing details.
The cholera bacterium secretes a protein toxin called choleragen. This toxin makes chloride ions and water leave epithelial cells and enter the lumen of the intestine. Fig. 6.1 shows the events that take place in cells lining the intestine when choleragen attaches to the membrane of one of these cells.
State one probable source of an outbreak of cholera.
With reference to Fig. 6.1, state why choleragen molecules are described as having quaternary structure.
State the type of cell membrane component that acts as the receptor for choleragen.
The movement of chloride ions out of the epithelial cell needs energy. Name the phosphorylated nucleotide required for this process.
Explain why water also moves from epithelial cells into the lumen of the intestine when choleragen is present.