exam qs lqc 6b

Question 1

Describe the role of the CFTR protein in ensuring that the mucus produced in the lungs has the right consistency.

Answer 1

chloride ions leave cells through CFTR channel protein, sodium ions leave the cells, increasing the solute concentration in the mucus, water moves out of the cells by osmosis into the mucus

Question 2

Explain why this change in the primary structure would result in the CFTR protein being non-functional.

Answer 2

mutation causes a change in the number of amino acids therefore bonding will be different, resulting in a change in 3D shape therefore it can’t transport chloride ions

Question 3

Explain the effects of having smaller quantities of CFTR protein in membranes.

Answer 3

fewer chloride ions transported across cell membrane, less regulation of the sodium ion channel, therefore less water moves from the cell into the mucus by osmosis, this makes mucus more viscous, cilia cannot remove mucus, resulting in blockage of airways