ABSORPTION IN HUMANS

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 After digestion the food needs to be absorbed.before that the digested food needs to be transported to each and every part of the body.


ABSORPTION and ASSIMILATION IN HUMANS


After digestion food is converted into soluble form i.e (carbs into glucose/ fats into glycerol/ proteins into amino acids).so these soluble molecules are absorbed by cells of body to assimilate(PRODUCE ENERGY)


Absorption occurs in small and large intestine.mainly nutrients are absorbed by small intestine and water by large intestine.


Being soluble, these products are easily absorbed by capillaries.The internal regions of the small intestine are folded into numerous finger-like projections called VILLI. 

They increase the absorptive surface area for absorption.











Villi are richly supplied with blood capillaries and also contained lymph vessels.


Each villus has its cell membrane of the lumen side again folded into microscopic processes, called microvilli.


Large intestine is present after and  does not have villi. It is divided into two parts- 1. Colon, the larger part

                        2. Rectum followed by anus.


Apart from absorption ,undigested food is also collected as faeces in rectum. The rectal wall absorbs water from faeces and also add mucus to it .Finally faecal matter is ejected out by anal sphincter.


The absorbed food goes into the blood and moves along with blood stream. This food reaches to the cells where it is utilised, so, utilisation of food is also a part of nutrition and is called assimilation.

Digested food mainly consists of- 

 Glucose

 Fructose

 Galactose

 Amino acids

Nucleotides

Fattyacids etc.


These simple molecules are used for


  •  Building components of cells and tissue


  •  Repairing injured cells


  •   They are broken down by catabolic processes to produce energy


For digestion notes click here- digestion in humans

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