A Moving to another question willsave this response Cholera 2 points Save Answer

Question

A Moving to another question willsave this response Cholera 2 points Save Answer produce is an infection of the small intestine by some strains of the Vibrio cholerae. The classic large amounts of watery diarrhea that lastsasew days. me cholera bactera symptom is a toxin that stimulates the secretion of Na*.K .Cr.and HCO3 into the lumen interior space the smalintestine. How are these ions (highlycharged polar moiocules crossing the plasma membrane of intestinal cells against their gradient? lons can easily cross the plasma membrane lons can use facilitated diffusion to move against a gradient The cell had to invest energy in order to concentrate ions outside O lons will remain outside of the cell even if a sodum ohannel opens up. Moving to another question will save this response. Question 20 of

Explanation / Answer

Ans : Ions Can used Facilitaed diffusion to move against a gradient.

1.Ions (charged atoms) can pass allow to make in or out of the cells because of ion channels are membrane proteins,some ions open because of changes in volage and others open because chemical binding to them,dehydration in cholera is due to chloride ion channels

2.Chloride ion channel is cystic fibrosis transmembrane conductance Regulator (CFTR) which allows ions to flow out of cells,CFTR channel used to adjust water level cells of small intestine,higher concentration of chloride ions outside the cell cause water to leave outside to cell by osmosis process.

3.The cholera toxin binds to receptors on cells in the wall of the small intestine and activates cyclic AMP (cyclic adenosine mono phosphate, a messenger molecule), increasing the number of cyclic AMP molecules in the cell.

4.As CFTR channels are activated by cyclic AMP, the increased concentration of cyclic AMP causes the CFTR channels to open and stay open. This means that chloride ions (Cl–) move out of the cell into the lumen ( small intestine). Sodium ions (Na+) are attracted to the negative chloride ions,hence they also leave the cell.

5.With more ions in the lumen, the lumen has a lower water potential. This makes water leave the cells lining the lumen by osmosis, down the concentration gradient. The cells lose a lot of water, which causes severe dehydration, and the increased water in the small intestine causes watery diarrhea and vomiting

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.