Nutrition and the Human Digestive System

Question 7:(a) Explain why a diet rich in fats is not good for health.(b) Suggest suitable types of food for someone who wants to reduce weight and reduce the risk of contracting cardiovascular disease. Explain your answer.(c) Explain the processes of starch digestion, absorption and assimilation in the human body. Answer:(a) A diet rich in … Read more

Question 5:Explain the processes that fat molecules undergo starting from the duodenum until it is finally used by body cells. Answer:• Lipid digestion begins in the duodenum.• Bile salts produced by the liver emulsify fats into lipid droplets.• Pancreas secretes pancreatic juice which contains lipase into the duodenum.• Lipase hydrolyses lipid droplets to fatty acids … Read more

Question 1:Some people cannot drink milk because it causes diarrhoea and a bloated stomach. Explain why. Answer:The intestinal juice of the individual may possibly not contain or lacks lactase to digest milk sugar (lactose) in the small intestine. As a result, the bacteria in the large intestine will digest the lactose to yield fatty acids … Read more

Question 1:In your opinion, why is fibre important in the defaecation process. Explain your answer. Answer:The intake of a high-fibre diet facilitates the movement of faeces and prevents health conditions such as constipation, colon cancer, rectal cancer and haemorrhoids. Some of the functions of fibres are to stimulate peristalsis, absorb and dispose off toxins, regulate … Read more

Question 1:State the main function of the large intestine. Answer:The main functions of the large intestine are water and vitamin reabsorption, and faeces formation. Question 2:What are the substances absorbed in the large intestine? Answer:Water, minerals, the metabolic by-products of bacteria such as vitamin B, K and folic acid. Question 3:Explain the importance of water … Read more

Question 1:State the meaning of assimilation. Answer:Assimilation refers to the use of absorbed nutrients to synthesise complex compounds. Question 2:Explain the functions of the liver in the assimilation of digested food. Answer:The functions of liver in assimilation:• Carbohydrate metabolism Glucose is oxidised to yield energy. Most of the excess glucose are converted to glycogen and … Read more

Question 1:Name the main structures for the absorption of digested food. Answer:The main structure in food absorption is villi. Question 2:Name the structure in the villus involved in the transporting of the following nutrients:(a) amino acids(b) vitamins A and E Answer:(a) Blood capillaries(b) Lacteal Question 3:Explain the adaptations of the small intestine to increase the … Read more

Question 1:Explain the importance of the digestion process for humans. Answer:The food consumed by humans is in the form of large and complex molecules. The food needs to be broken down to a smaller and simpler form that can diffuse into the blood vessels and transported to body cells. Question 2:Name the structures in the … Read more