write the mode of nutrition in animals and different ways of taking food and digestion in human digestion in grass eating animals and with which each diagram
Answers
Answer:
the mode of nutrition in animals is holozoic (heterotrophic) type of nutrition.
Explanation:
Nutrition and digestion are the main characteristics of living entities and are inter-related. Nutrition is obtained from food after the process of digestion. Animal nutrition covers topics such as the requirement of nutrients, mode of intake, utilization of food in the body. Some nutrients are complex in nature and cannot be utilized directly. They require to be broken down into simpler substances, this process is called digestion.
Food is consumed differently by different entities. Hummingbirds and bees suck nectar of plants, snakes swallow their prey, fish feed on floating food particles etc. Digestion is carried out by the digestive system consisting of distinct organs.
Digestion in humans is carried out by an organized and distinct digestive system. Food is ingested through the mouth and enters into the food pipe or oesophagus through the pharynx and finally to the stomach. On reaching the stomach, complex food is broken down into simpler substances by secreting digestive juices with the absorption of nutrients. Undigested food is further directed to small and large intestine which carries out further absorption. Unwanted waste is directed to the rectum for excretion.
Grass eating animals are known as ruminants. Animals like cows, goats and buffaloes eat grass. These animals swallow grass quickly and store in a sac-like structure called rumen. Rumen forms the first stomach and is four-chambered. Here, food is partially digested and is called the cud. Plants contain cellulose in large quantities. Cellulose is a complex structure which is broken down into simpler particles in the rumen. The process where cud returns to the mouth in small lumps for ruminants to chew is called rumination.
Rumination is aided by bacteria present in the rumen which breaks down cellulose in plants. The digested food is then passed to the reticulum. Some animals including humans cannot digest cellulose for its complex structure.
Some animals have a large sac-like structure called caecum which is present between the food pipe or the oesophagus and the small intestine. For example Rabbit, Horses. Cellulose in food is digested by the action of bacteria which humans do not possess.
Plants make their food by the process of photosynthesis, but animals cannot make their food themselves. Animals get their food from plants. Some animals eat plants directly while some animals eat plant eating animals. Thus, animals get their food from plants either directly or indirectly.
All organisms require food for survival and growth. Requirement of nutrients, the mode of intake of food and its utilization in body are collectively known as nutrition.
Nutrition in complex animals involves following steps:
Ingestion
Digestion
Absorption
Assimilation
Egestion
Human beings use their hands to put food into their mouth and swallow the food after chewing.
Infants of human and many other animals feed upon their mother’s milk by sucking them.