Biology aqa A level Common Questions and Answers 2024

Biology aqa A level Common Questions and Answers 2024 give two factors other than age and gender that would affect the concentration of creatinine in the blood ? - Correct Answer muscle/ body mass ethnicity Explain how the cells of the collecting duct are able to absorb water from the filtrate through the protein channels in their plasma membranes? - Correct Answer lower w.p/ more negative inside tubule cells so h2o enters by osmosis Suggest why diabetes insipidus is more common in males ? - Correct Answer Bc males only have X chromosome do not have Y chromosome single copy of recessive allele will be expressed A recessive allele which has harmful effects is able to reach a higher frequency in a population than a harmful dominant allele. Explain how ? - Correct Answer recessive allele can be carried by individuals showing effects dominant allel always expressed organisms that are affected are more likely to reproduce therefore recessive alleles are more likely to be passed on In some forms of kidney disease, proteins from the blood plasma are found in the urine. Which part of the nephron would have been damaged by the disease to cause proteins from blood plasma to be present in the urine? Explain your answer - Correct Answer glomerulus/ bowmans capsule basement membrane proteins are large molecules cannot normally pass through filter can only pass through if filter damaged Describe the role of the hormone glucagon in the control of blood sugar concentration ? - Correct Answer glucagon binds to specific receptor on liver cells activation of enzymes in liver hydrolysis of glycogen F.D of glucose out of liver cells increases blood glucose levels