0610_s22_qp_41
A paper of Biology, 0610
Questions:
6
Year:
2022
Paper:
4
Variant:
1

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The pancreas is an organ that has roles in the digestive and hormonal systems of humans. shows part of the alimentary canal and some of the associated organs. stomach pancreas pancreatic duct J K L State the names of organs J, K and L. J K L The pancreas secretes hormones into the blood and enzymes into the pancreatic duct. The enzymes are released into the alimentary canal. Complete Table 3.1 by stating the hormones and enzymes that are secreted by the pancreas. Table 3.1 hormones secreted by the pancreas enzymes secreted by the pancreas Chloride ions also move along the pancreatic duct. CFTR proteins in the cells lining the pancreatic duct move chloride ions out of the cells into the duct. is a diagram of a cell from the lining of the pancreatic duct showing the location and activity of CFTR proteins. Key: chloride ion not to scale inside the pancreatic duct pancreatic duct cell CFTR protein Explain how CFTR proteins move chloride ions across the membrane of the cell shown in . The movement of chloride ions into the pancreatic duct causes water to move from the cells into the duct to help the flow of liquid in the duct. Explain how water moves from the cell shown in into the pancreatic duct. If CFTR proteins do not move chloride ions, the liquid in the pancreatic duct becomes very sticky and the duct can become blocked. Blocked pancreatic ducts are one effect of cystic fibrosis, which is an inherited disease. Cystic fibrosis is caused by a mutation of the gene that codes for the CFTR protein. shows the pedigree diagram of a family that has two people who have cystic fibrosis. female without cystic fibrosis male without cystic fibrosis female with cystic fibrosis male with cystic fibrosis Key: The allele that causes cystic fibrosis is a recessive allele. Describe and explain the evidence shown in that cystic fibrosis is caused by a recessive allele. Person 7 is expecting a child with a man who is heterozygous for cystic fibrosis. Complete the genetic diagram to predict the probability of person 7 and the heterozygous man having a child with cystic fibrosis. Use the symbol A for the dominant allele and a for the recessive allele. parental genotypes gametes + genotypes of offspring phenotypes of offspring probability of having a child with cystic fibrosis
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Researchers investigated the effect of adding cattle manure (cattle faeces) to fields where snap bean plants, Phaseolus vulgaris, were grown. Cattle manure contains some protein. Explain how protein in the cattle manure is converted to the type of ions that plants can absorb. Snap bean plants are legumes which have root nodules that contain nitrogen‑fixing bacteria. shows some root nodules. root nodules Suggest the advantage to farmers of having snap bean plants that have a large number of root nodules. The researchers investigated the effect of adding cattle manure to fields of snap bean plants. • Field 1 was treated with a small quantity of cattle manure. • Field 2 was treated with a medium quantity of cattle manure. • Field 3 was treated with a large quantity of cattle manure. • Field 4 was not treated with any cattle manure. The researchers counted the number of root nodules on samples of plants from each field when the snap beans were harvested. The results of the investigation are shown in . field average number of root nodules per plant Calculate the percentage increase in the average number of root nodules per plant when snap bean plants were grown with a large quantity of cattle manure (field 3) compared with no cattle manure (field 4). Give your answer to two significant figures. Space for working. % When large quantities of manure are put on fields it can lead to eutrophication of streams and rivers. This can lead to the death of fish. Describe how eutrophication of streams and rivers can lead to the death of fish.
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