) Part (b) Part (c) Part (d) Part (e) Part (a) Answer    75% like this The main steps of nutrition in humans are __________, __________, __________, _________ and __________. See More 01:40 Step-by-step video explanation Part (a), 2.2 Exercises, Page 20, 2. Nutrition in Animals Solution details HIDE ALL Tip Nutrition is the energy and nourishment that is obtained from consuming food in living organisms. Explanation The process of taking in food for the purpose of growth, metabolism, and repair is known as nutrition. There are five main steps involved in nutrition in humans that includes, ingestion, digestion, absorption, assimilation and egestion. Ingestion refers to a process of taking food, drink, or any other substance into the body either by swallowing or absorbing it. The food is taken inside the mouth by ingesting it. Digestion is the process of breaking complex food materials into simpler forms. The ingested food is further digested by the body eg. Polysaccharides (complex sugars) are converted into monosaccharides (simple sugars) by the process of digestion. Absorption is an important process by which the digested food is absorbed by the blood and is further supplied to the rest of the body. Assimilation refers to the process of absorption of crucial vitamins, minerals, and other chemicals from the food within the GI tract of the human body by chemical breakdown as well as physical breakdown. Egestion also known as excretion or defecation is the process of discharging or discarding undigested materials known as waste material from either a cell or an entire organism. Final Answer The main steps of nutrition in humans are ingestion, digestion, absorption, assimilation and egestion. Did you find what you were looking for? Part (b) Answer    73% like this The largest gland in the human body is __________. 00:52 Step-by-step video explanation Part (b), 2.2 Exercises, Page 20, 2. Nutrition in Animals Solution details HIDE ALL Tip The liver is a large and lobed glandular organ situated in the abdomen of vertebrates and is involved in several metabolic processes. Explanation The liver is the largest organ in the body which is situated in the upper part of the abdomen placed on the right side. It helps in secretion of bile juices that help in the decomposition of lipids and vitamins. The liver stores bile in Gall Bladder where it is further released into duodenum thus helping in the digestion of fats. It also helps in preparation of proteins for blood plasma enabling blood clotting as well as detoxification. The liver also absorbs excess glucose from the blood and releases it back when needed. Final Answer The largest gland in the human body is the liver. Did you find what you were looking for? Part (c) Answer    71% like this The stomach releases hydrochloric acid and ___________ juices which act on food. 01:42 Step-by-step video explanation Part (c), 2.2 Exercises, Page 20, 2. Nutrition in Animals Solution details HIDE ALL Tip Digestive juices are secreted by various glands of the body during the process of digestion. Explanation The digestive system contains several organs contributing to the secretion of digestive juices, these organs include salivary glands, stomach, liver, pancreas as well as small intestine involved in secretion of digestive juices. The salivary glands secrete salivary amylase that helps in the breakdown of complex polymers of glucose (e.g. starch). The stomach produces various acids which help in the chemical breakdown of food. The liver produces bile that is responsible for the emulsification of fats. The pancreas secretes bicarbonate ions into the duodenum to neutralise acids of the stomach and in also involved in secretion of lipase, amylase and protease for fat, carbohydrate and protein digestion respectively. The small intestine secretes intestinal juices from crypts of Leiberkuhn. These juices neutralize hydrochloric acid originating from the stomach, releases GI hormones in the bloodstream and contain digestive enzymes facilitating the digestion as well as absorption of food.
