NUTRATION IN PLANTS

NUTRTION IN ANIMALSPlants 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, mode of intake of food and its utilization in body are collectively known as nutrition.

STEPS INVOLVED IN NUTRIENTS•INGESTION•DIGESTION•ABSORPTION•ASSIMILATION•EGESTION

INGESTIONIngestion is the consumption of a substance by an organism. In animals, it normally is accomplished by taking in the substance through the mouth into the gastrointestinal tract, such as through eating or drinking. In single-celled organisms, ingestion can take place through taking the substance through the cell membrane.Besides nutritional items, other substances which may be ingested include medication (where ingestion is termed oral administration), recreational drugs, and substances considered inedible such as foreign bodies or excrement. Ingestion is a common route taken by pathogenic organisms and poisons entering the body.Ingestion can also refer to a mechanism picking up something and making it enter an internal hollow of that mechanism, e.g. "a grille was fitted to prevent the pump from ingesting driftwood".

Some pathogens are transmitted via ingestion, including viruses, bacteria, and parasites. Most commonly, this takes place via the faecal-oral route. An intermediate step is often involved, such as drinking water contaminated by faeces or food prepared by workers who fail to practice adequate hand-washing, and is more common in regions whereuntreated sewage is common. Diseases transmitted via the fecal-oral route include hepatitis A, polio, and cholera .Pica is an abnormal appetite for non-nutritive objects or for food items in a form not normally eaten, such as flour. Coprophagia is the consumption of feces, an abnormal ingestive behavior common in some animals.

Digestion is the breakdown of large insoluble food molecules into small water-soluble food molecules so that they can be absorbed into the watery blood plasma. In certain organisms, these smaller substances are absorbed through the small intestine into the blood stream. Digestion is a form of catabolism that is often divided into two processes based on how food is broken down: mechanical and chemical digestion. The term mechanical digestion refers to the physical breakdown of large pieces of food into smaller pieces which can subsequently be accessed by digestive enzymes. In chemical digestion, enzymes break down food into the small molecules the body can use.

Digestion 

In the human digestive system, food enters the mouth and mechanical digestion of the food starts by the action of mastication(chewing), a form of mechanical digestion, and the wetting contact of saliva. Saliva, a liquid secreted by the salivary glands, containssalivary amylase, an enzyme which starts the digestion of starch in the food; the saliva also contains mucus, which lubricates the food, and hydrogen carbonate, which provides the ideal conditions of pH (alkaline) for amylase to work. After undergoing mastication and starch digestion, the food will be in the form of a small, round slurry mass called a bolus. It will then travel down the esophagus and into the stomach by the action of peristalsis. Gastric juice in the stomach starts protein digestion. Gastric juice mainly containshydrochloric acid and pepsin. As these two chemicals may damage the stomach wall, mucus is secreted by the stomach, providing a slimy layer that acts as a shield against the damaging effects of the chemicals. At the same time protein digestion is occurring, mechanical mixing occurs by peristalsis, which is waves of muscular contractions that move along the stomach wall. This allows the mass of food to further mix with the digestive enzymes.

Absorption – The process of passing of digested food into blood vessels in the intestine is called the absorption.

Absorption

ASSIMILATIONAssimilation – The conversion of absorbed food in complex substances such as proteins and vitamins required by body is called assimilation.In other words, assimilation is the conversion of absorbed food (nutrients) into living tissues. Through the process of assimilation our cells are supplied with oxygen and nutrients.

Egestion – Removal of waste materials from the body is called Egestion. The faecal matter is removed through the anus from time-to-time.Since the waste of food left after digestion is also called faeces, hence the process of Egestion is also known as defecation.

Egestion

1. WHAT ARE THE STEPS INVOLVED IN NUTRIENTS •ANSWER. INGESTION,DIGESTION,ABSORPTION,ASSIMILATION,EGESTION

2. WHAT IS ASSIMILATION

ANSWER. The conversion of absorbed food in complex substances such as proteins and vitamins required by body is called assimilation.

THANAK

YOU DONE BY:MOHAMED NAVEEDJIBRAN