Biology 9700 · AS & A Level · Passage of information from parents to offspring
Passage of information from parents to offspring — practice question
Diabetes insipidus (DI) is a disorder that causes intense thirst and the passing of very large volumes of dilute urine. One important cause of DI is a lack of ADH. ADH normally attaches to receptor proteins in the cell surface membranes of cells in the collecting ducts of nephrons.
(a)[3]
Outline how ADH affects the collecting ducts.
(b(i))[1]
Explain what sex linkage means.
(b(ii))[4]
Use a genetic diagram to show how parents who do not have this condition can have a child with the inherited form of DI. Use symbols, and show the parental genotypes, gametes, offspring genotypes and offspring phenotypes.
Worked solution & mark scheme
This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Mentions enzyme/phosphorylase/signalling” …