Animal Nutrition Worksheet-2.pdf

Animal Nutrition Worksheet 1 Fig. 2.1 is a diagram of the human alimentary canal and associated organs. 1 2...

Animal Nutrition Worksheet 1 Fig. 2.1 is a diagram of the human alimentary canal and associated organs. 1 2 7 3 4 5 6 Fig. 2.1 (a) Table 2.1 shows enzymes, the organs that secrete these enzymes, their substrates and products. Complete Table 2.1. Table 2.1 number organ that secretes identifying enzyme substrate product or products the enzyme the organ on Fig. 2.1 amylase 1 3 protein lipase 4 maltase © UCLES 2022 0610/42/O/N/22  (b) Explain the role of hydrochloric acid in the alimentary canal................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ (c) State a function of the region of the alimentary canal labelled 6 in Fig. 2.1.................................................................................................................................................................................................................................................................................................................................................................................................................................................... (d) Describe how food eaten by humans is reduced to smaller pieces and explain how this makes chemical digestion more efficient. You may refer to Fig. 2.1 in your answer.................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. [Total: 14] © UCLES 2022 0610/42/O/N/22 [Turn over 2 (a) Digestive enzymes are secreted into the alimentary canal. (i) As well as enzymes, other substances that are important for digestion are also secreted into the alimentary canal. State the names of two of these other substances. 1........................................................................................................................................ 2........................................................................................................................................ (ii) Table 2.1 summarises some facts about the enzymes that are secreted into the alimentary canal. Complete Table 2.1. Table 2.1 products of organ where the organ when the name of the enzyme digestion involving this enzyme is secreted enzyme acts enzyme salivary glands pepsin pancreas fatty acids and glycerol epithelial lining of the small intestine small intestine © UCLES 2022 0610/43/O/N/22 [Turn over  6 (b) The activity of the enzyme pepsin was measured at different temperatures. The results are shown in Fig. 2.1. 3000 2500 2000 enzyme activity 1500 / U per mg protein 1000 500 0 10 20 30 40 50 60 70 temperature / °C Fig. 2.1 © UCLES 2022 0610/43/O/N/22  7 Describe and explain the effect of temperature on the activity of pepsin. Use the information in Fig. 2.1 to support your answer.................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. (c) Lactase is another digestive enzyme, which is produced by human babies. (i) Explain why lactase is important for the nutrition of young babies.................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. (ii) Most people stop producing lactase when they become adults. If they drink milk, this may give them diarrhoea. Describe the symptoms of diarrhoea............................................................................................................................................................................................................................................................................................................................................................................................................................ © UCLES 2022 0610/43/O/N/22 [Turn over  (iii) Cholera can also cause diarrhoea. Explain how the cholera bacterium causes diarrhoea........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ [Total: 18] © UCLES 2022 0610/43/O/N/22 3 (a) Fig. 1.1 is a side view of a human skull indicating the four types of teeth and the jaws. upper jaw incisors canine premolar molars lower jaw Fig. 1.1 (i) State the function of human teeth............................................................................................................................................................................................................................................................................................................................................................................................................................ (ii) State the name of the visible outer layer of the teeth...................................................................................................................................... (iii) Explain the process of tooth decay in humans........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ © UCLES 2022 0610/41/O/N/22 [Turn over  6 4 Digestive enzymes catalyse the breakdown of large insoluble molecules. (a) (i) Explain why it is important that large insoluble molecules are broken down by chemical digestion.................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. (ii) State the name of the substance that is the solvent for most molecules that have been digested by enzymes...................................................................................................................................... (b) The activity of two protease enzymes, A and B, was measured at different pHs. Both enzymes are found in the human alimentary canal. The results are shown in Fig. 2.1. 900 140 enzyme A enzyme B 800 120 700 100 600 500 80 enzyme A activity enzyme B activity / U per mg 400 / U per mg 60 300 40 200 20 100 0 0 1 2 3 4 5 6 7 8 9 10 11 12 pH acid neutral alkaline Fig. 2.1 © UCLES 2022 0610/41/O/N/22  7 Describe and explain the roles of the two protease enzymes, A and B, in the alimentary canal. Use the information in Fig. 2.1 to support your answer.................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. (c) Maltase is a digestive enzyme that acts in the small intestine. State the exact location of maltase in the small intestine.............................................................................................................................................. [Total: 10] © UCLES 2022 0610/41/O/N/22 [Turn over  14 5 (a) Table 6.1 shows some of the enzymes, their substrates, products and where they are 24 produced in the digestive system. Complete Table 6.1. Table 6.1 location of enzyme enzyme substrate product(s) production starch salivary glands............................................................ maltase maltose............................................................ amino acids stomach wall............................................................ pancreas and amino acids............................................................ small intestinal wall lipase fats............................................................ (b) Bile is made in the liver, stored in the gall bladder and passes into the small intestine. Describe the role of bile in digestion.................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. (c) After chemical digestion the products of digestion are absorbed. Define absorption............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................ © UCLES 2017 0610/42/F/M/17  15 (d) Lack of protein in the diet can result in protein-energy malnutrition. State the name of one disease caused by protein-energy malnutrition................................................................................................................................................ (e) People that eat a diet that is high in fats are often advised to reduce their intake of fats. Suggest the health benefits of this change in diet.................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. [Total: 15] © UCLES 2017 0610/42/F/M/17