Question

What is Digestion ?Describe briefly the process of digestion in man.​

Answer 1

A N S W E R :

$\underline{\mathcal{\orange{DIGESTION\::}}}$

Conversion of larger, complex & insoluble molecules of food material into smaller pieces, simple & soluble molecules with the help of digestive enzyme is called digestion.

It means digestion makes the nutrients of the food available of the body.

The digestion in different parts of alimentary canal is as follows :

$\underline{\mathcal{\orange{\bullet \:DIGESTION\:\:IN\:\:BUCCAL\:\:CAVITY\::}}}$

In buccal cavity, the food is chewed and mixed with saliva, Ptyalin enzyme is present in saliva, It acts on starch & converts into sugar (Maltose).

$\underline{\mathcal{\orange{\bullet \:OESOPHAGUS\::}}}$

It is also known as food-pipe and is 25-30 cm long muscular tube. It simply carries the food from pharynx to the stomach.

$\underline{\mathcal{\orange{\bullet \:DIGESTION\:\:IN\:\:STOMACH\::}}}$

The food grinder continuously in stomach due to peristalsis movement. The gastric juice from gastric gland mix in it. HCl, propepsin & prorenin, etc. are present in gastric juices. The proenzymes are activated by HCl and this protects the food for spoiling. Propepsin with the acid changes into pepsin & acts on protein of food. At the same time prorenin convert into renin and separate protein from milk. Pepsin effects proteins and they convert into peptones.

$\underline{\mathcal{\orange{\bullet \:DIGESTION\:\:IN\:\:DUODENUM\::}}}$

First bile juice and then pancreatic juices mixes in the chyme of duodenum. Bile juice is alkaline. If removes the acidity of food & activates the proenzymes of pancreatic juice.

Three types of enzymes are current in pancreatic juice:

1. Trypsin : Acts on semi-digested proteins and peptones and converts them into amino acid.
2. Amylopsin : Converts sugar and starch into glucose.
3. Steapsin : Acts on fats and converts them into fatty acids & glycerols.

$\underline{\mathcal{\orange{\bullet \:DIGESTION\:\:IN\:\:ILEUM\::}}}$

Intestinal juices are secreted from the glands of ileum. These are many enzymes in it, example, erepsin which converts rest of the protein into amino acid, Maltase, invertase, lactase, etc. which convert sugar to glucose and lipase converts fat into glycerol and fatty acids.

$\underline{\mathcal{\orange{\bullet \:ABSORPTION\::}}}$

After digestion, the molecules of food become so small that they can pass through the walls of the small intestine and go into our blood. This is called absorption.

$\underline{\mathcal{\orange{\bullet \:ASSIMILATION\::}}}$

The blood caries digested food to all parts of the body where it becomes assimilated as parts of the cells. This assimilated food is used by the body cells for obtaining energy as well as for growth & repair of the body.

Note :

Most of the digestion is completed in duodenum. Rest food is digested in ileum.

Answer 2

❮ᗩᑎSᗯEᖇ❯

Digestion Process

ᴛʜᴇ ᴘʀᴏᴄᴇꜱꜱ ᴏꜰ ᴅɪɢᴇꜱᴛɪᴏɴ ʙᴇɢɪɴꜱ ꜰʀᴏᴍ ᴛʜᴇ ᴍᴏᴜᴛʜ ᴀɴᴅ ᴇɴᴅꜱ ɪɴ ᴛʜᴇ ꜱᴍᴀʟʟ ɪɴᴛᴇꜱᴛɪɴᴇ – ᴛʜᴇ ʟᴀʀɢᴇ ɪɴᴛᴇꜱᴛɪɴᴇꜱ’ ᴍᴀɪɴ ꜰᴜɴᴄᴛɪᴏɴ ɪꜱ ᴛᴏ ᴀʙꜱᴏʀʙ ᴛʜᴇ ʀᴇᴍᴀɪɴɪɴɢ ᴡᴀᴛᴇʀ ꜰʀᴏᴍ ᴛʜᴇ ᴜɴᴅɪɢᴇꜱᴛᴇᴅ ꜰᴏᴏᴅ ᴀɴᴅ ᴇɴᴀʙʟᴇ ʙᴀᴄᴛᴇʀɪᴀʟ ꜰᴇʀᴍᴇɴᴛᴀᴛɪᴏɴ ᴏꜰ ᴍᴀᴛᴇʀɪᴀʟꜱ ᴛʜᴀᴛ ᴄᴀɴ ɴᴏ ʟᴏɴɢᴇʀ ʙᴇ ᴅɪɢᴇꜱᴛᴇᴅ.

ᴛʜᴇ ᴀʟɪᴍᴇɴᴛᴀʀʏ ᴄᴀɴᴀʟ ᴏʀ ᴛʜᴇ ɢᴀꜱᴛʀᴏɪɴᴛᴇꜱᴛɪɴᴀʟ ᴛʀᴀᴄᴛ ɪꜱ ᴀ ꜱᴇʀɪᴇꜱ ᴏꜰ ʜᴏʟʟᴏᴡ ᴏʀɢᴀɴꜱ ᴀɴᴅ ᴛᴜʙᴇꜱ ᴛʜᴀᴛ ʙᴇɢɪɴꜱ ꜰʀᴏᴍ ᴛʜᴇ ᴍᴏᴜᴛʜ ᴄᴀᴠɪᴛʏ ᴀɴᴅ ᴄᴏɴᴛɪɴᴜᴇꜱ ɪɴᴛᴏ ᴛʜᴇ ᴘʜᴀʀʏɴx, ᴛʜʀᴏᴜɢʜ ᴛʜᴇ ꜱᴛᴏᴍᴀᴄʜ, ꜱᴍᴀʟʟ ɪɴᴛᴇꜱᴛɪɴᴇꜱ, ʟᴀʀɢᴇ ɪɴᴛᴇꜱᴛɪɴᴇꜱ, ᴀɴᴅ ꜰɪɴᴀʟʟʏ ᴇɴᴅɪɴɢ ᴀᴛ ᴛʜᴇ ᴀɴᴜꜱ. ꜰᴏᴏᴅ ᴘᴀʀᴛɪᴄʟᴇꜱ ɢʀᴀᴅᴜᴀʟʟʏ ɢᴇᴛ ᴅɪɢᴇꜱᴛᴇᴅ ᴀꜱ ᴛʜᴇʏ ᴛʀᴀᴠᴇʟ ᴛʜʀᴏᴜɢʜ ᴠᴀʀɪᴏᴜꜱ ᴄᴏᴍᴘᴀʀᴛᴍᴇɴᴛꜱ ᴏꜰ ᴛʜᴇ ɢᴀꜱᴛʀᴏɪɴᴛᴇꜱᴛɪɴᴀʟ ᴛʀᴀᴄᴛ.

The digestion process takes place in the following steps.

➊Ingestion

┅┅┅┅┅┅┅┅

ᴛʜᴇ ᴠᴇʀʏ ꜰɪʀꜱᴛ ꜱᴛᴇᴘ ɪɴᴠᴏʟᴠᴇꜱ ᴍᴀꜱᴛɪᴄᴀᴛɪᴏɴ (ᴄʜᴇᴡɪɴɢ). ᴛʜᴇ ꜱᴀʟɪᴠᴀʀʏ ɢʟᴀɴᴅꜱ, ᴀʟᴏɴɢ ᴡɪᴛʜ ᴛʜᴇ ᴛᴏɴɢᴜᴇ, ʜᴇʟᴘꜱ ᴛᴏ ᴍᴏɪꜱᴛᴇɴ ᴀɴᴅ ʟᴜʙʀɪᴄᴀᴛᴇ ꜰᴏᴏᴅ, ʙᴇꜰᴏʀᴇ ʙᴇɪɴɢ ᴘᴜꜱʜᴇᴅ ᴅᴏᴡɴ ɪɴᴛᴏ ᴛʜᴇ ꜰᴏᴏᴅ ᴘɪᴘᴇ.

➋Mixing and Movement

┅┅┅┅┅┅┅┅┅┅┅┅┅┅┅┅┅

ɪᴛ ɪɴᴠᴏʟᴠᴇꜱ ᴛʜᴇ ᴘʀᴏᴄᴇꜱꜱ ᴏꜰ ʟᴜʙʀɪᴄᴀᴛɪɴɢ ᴀɴᴅ ᴍᴀɴɪᴘᴜʟᴀᴛɪɴɢ ꜰᴏᴏᴅ ᴀɴᴅ ᴘᴜꜱʜɪɴɢ ɪᴛ ᴅᴏᴡɴ ᴛʜᴇ ꜰᴏᴏᴅ ᴛʜʀᴏᴜɢʜ ᴛʜᴇ ꜰᴏᴏᴅ ᴘɪᴘᴇ (ᴜꜱɪɴɢ ᴘᴇʀɪꜱᴛᴀʟꜱɪꜱ), ᴀɴᴅ ɪɴᴛᴏ ᴛʜᴇ ꜱᴛᴏᴍᴀᴄʜ.

➌Secretion

┅┅┅┅┅┅┅┅

ᴛʜᴇ ꜱᴛᴏᴍᴀᴄʜ, ꜱᴍᴀʟʟ ɪɴᴛᴇꜱᴛɪɴᴇ, ʟɪᴠᴇʀ, ᴀɴᴅ ᴘᴀɴᴄʀᴇᴀꜱ ꜱᴇᴄʀᴇᴛᴇ ᴇɴᴢʏᴍᴇꜱ ᴀɴᴅ ᴀᴄɪᴅꜱ ᴛᴏ ᴀɪᴅ ᴛʜᴇ ᴘʀᴏᴄᴇꜱꜱ ᴏꜰ ᴅɪɢᴇꜱᴛɪᴏɴ. ɪᴛ ꜰᴜɴᴄᴛɪᴏɴꜱ ʙʏ ʙʀᴇᴀᴋɪɴɢ ᴅᴏᴡɴ ꜰᴏᴏᴅ ᴘᴀʀᴛɪᴄʟᴇꜱ ɪɴᴛᴏ ꜱɪᴍᴘʟᴇ ᴄᴏᴍᴘᴏɴᴇɴᴛꜱ ᴀɴᴅ ᴇᴀꜱɪʟʏ ᴀʙꜱᴏʀʙᴀʙʟᴇ ᴄᴏᴍᴘᴏɴᴇɴᴛꜱ.

➍Digestion

┅┅┅┅┅┅┅

ᴛʜᴇ ᴘʀᴏᴄᴇꜱꜱ ᴏꜰ ᴄᴏɴᴠᴇʀᴛɪɴɢ ᴄᴏᴍᴘʟᴇx ꜰᴏᴏᴅ ᴘᴀʀᴛɪᴄʟᴇꜱ ɪɴᴛᴏ ꜱɪᴍᴘʟᴇʀ ꜱᴜʙꜱᴛᴀɴᴄᴇꜱ ɪɴ ᴛʜᴇ ᴘʀᴇꜱᴇɴᴄᴇ ᴏꜰ ᴇɴᴢʏᴍᴇꜱ ᴀɴᴅ ᴀᴄɪᴅꜱ ꜱᴇᴄʀᴇᴛᴇᴅ ʙʏ ᴅɪꜰꜰᴇʀᴇɴᴛ ᴅɪɢᴇꜱᴛɪᴠᴇ ᴏʀɢᴀɴꜱ.

➎Absorption

┅┅┅┅┅┅┅┅

ᴛʜɪꜱ ᴘʀᴏᴄᴇꜱꜱ ʙᴇɢɪɴꜱ ɪɴ ᴛʜᴇ ꜱᴍᴀʟʟ ɪɴᴛᴇꜱᴛɪɴᴇ ᴡʜᴇʀᴇ ᴍᴏꜱᴛ ᴏꜰ ᴛʜᴇ ɴᴜᴛʀɪᴇɴᴛꜱ ᴀɴᴅ ᴍɪɴᴇʀᴀʟꜱ ᴀʀᴇ ᴀʙꜱᴏʀʙᴇᴅ. ᴛʜᴇ ᴇxᴄᴇꜱꜱ ᴡᴀᴛᴇʀ ɪɴ ᴛʜᴇ ɪɴᴅɪɢᴇꜱᴛɪʙʟᴇ ᴍᴀᴛᴛᴇʀ ɪꜱ ᴀʙꜱᴏʀʙᴇᴅ ʙʏ ᴛʜᴇ ʟᴀʀɢᴇ ɪɴᴛᴇꜱᴛɪɴᴇꜱ.

➏Excretion

┅┅┅┅┅┅┅

ᴛʜᴇ ᴘʀᴏᴄᴇꜱꜱ ᴏꜰ ʀᴇᴍᴏᴠɪɴɢ ɪɴᴅɪɢᴇꜱᴛɪʙʟᴇ ꜱᴜʙꜱᴛᴀɴᴄᴇꜱ ᴀɴᴅ ᴡᴀꜱᴛᴇ ʙʏ-ᴘʀᴏᴅᴜᴄᴛꜱ ꜰʀᴏᴍ ᴛʜᴇ ʙᴏᴅʏ ᴛʜʀᴏᴜɢʜ ᴛʜᴇ ᴘʀᴏᴄᴇꜱꜱ ᴏꜰ ᴅᴇꜰᴇᴄᴀᴛɪᴏɴ.

In a nutshell, the digestion process consists of the six following steps:

Ingestion ⇒Mixing and Movement ⇒ Secretion ⇒ Digestion ⇒Absorption ⇒Excretion

Functions of the Human Digestive System

➊ᴅɪɢᴇꜱᴛɪᴏɴ ᴀɴᴅ ᴀʙꜱᴏʀᴘᴛɪᴏɴ ᴀʀᴇ ᴛʜᴇ ᴛᴡᴏ ᴍᴀɪɴ ꜰᴜɴᴄᴛɪᴏɴꜱ ᴏꜰ ᴛʜᴇ ᴅɪɢᴇꜱᴛɪᴠᴇ ꜱʏꜱᴛᴇᴍ.

➋ᴅɪɢᴇꜱᴛɪᴏɴ ɪꜱ ɴᴇᴄᴇꜱꜱᴀʀʏ ꜰᴏʀ ʙʀᴇᴀᴋɪɴɢ ᴅᴏᴡɴ ꜰᴏᴏᴅ ᴘᴀʀᴛɪᴄʟᴇꜱ ɪɴᴛᴏ ɴᴜᴛʀɪᴇɴᴛꜱ ᴛʜᴀᴛ ᴀʀᴇ ᴜꜱᴇᴅ ʙʏ ᴛʜᴇ ʙᴏᴅʏ ᴀꜱ ᴀɴ ᴇɴᴇʀɢʏ ꜱᴏᴜʀᴄᴇ, ᴄᴇʟʟ ʀᴇᴘᴀɪʀ ᴀɴᴅ ɢʀᴏᴡᴛʜ.

➌ꜰᴏᴏᴅ ᴀɴᴅ ᴅʀɪɴᴋ ɴᴇᴇᴅ ᴛᴏ ʙᴇ ᴄᴏɴᴠᴇʀᴛᴇᴅ ɪɴᴛᴏ ꜱᴍᴀʟʟᴇʀ ᴍᴏʟᴇᴄᴜʟᴇꜱ ᴏꜰ ɴᴜᴛʀɪᴇɴᴛꜱ ʙᴇꜰᴏʀᴇ ɪᴛ ɪꜱ ᴀʙꜱᴏʀʙᴇᴅ ʙʏ ᴛʜᴇ ʙʟᴏᴏᴅ ᴀɴᴅ ᴄᴀʀʀɪᴇᴅ ᴛᴏ ᴛʜᴇ ᴄᴇʟʟꜱ ᴛʜʀᴏᴜɢʜᴏᴜᴛ ᴛʜᴇ ʙᴏᴅʏ. ᴛʜᴇ ʙᴏᴅʏ ʙʀᴇᴀᴋꜱ ᴛʜᴇ ɴᴜᴛʀɪᴇɴᴛꜱ ᴘʀᴇꜱᴇɴᴛ ɪɴ ᴛʜᴇ ᴅʀɪɴᴋꜱ ᴀɴᴅ ꜰᴏᴏᴅ ɪɴᴛᴏ ᴄᴀʀʙᴏʜʏᴅʀᴀᴛᴇꜱ, ᴠɪᴛᴀᴍɪɴꜱ, ꜰᴀᴛꜱ ᴀɴᴅ ᴘʀᴏᴛᴇɪɴꜱ.

What are accessory organs?

ᴀᴄᴄᴇꜱꜱᴏʀʏ ᴏʀɢᴀɴꜱ ᴀʀᴇ ᴏʀɢᴀɴꜱ ᴡʜɪᴄʜ ᴀʀᴇ ɴᴏᴛ ᴘᴀʀᴛ ᴏꜰ ᴛʜᴇ ᴅɪɢᴇꜱᴛɪᴠᴇ ꜱʏꜱᴛᴇᴍ; ʜᴏᴡᴇᴠᴇʀ, ᴛʜᴇʏ ᴀɪᴅ ɪɴ ᴛʜᴇ ᴅɪɢᴇꜱᴛɪᴏɴ ᴘʀᴏᴄᴇꜱꜱ ʙʏ ᴘᴇʀꜰᴏʀᴍɪɴɢ ᴍᴀɴʏ ꜱᴇᴄᴏɴᴅᴀʀʏ ꜰᴜɴᴄᴛɪᴏɴꜱ. ᴛʜᴇ ᴍᴀɪɴ ᴀᴄᴄᴇꜱꜱᴏʀʏ ᴏʀɢᴀɴꜱ ᴏꜰ ᴛʜᴇ ᴅɪɢᴇꜱᴛɪᴠᴇ ꜱʏꜱᴛᴇᴍ ᴀʀᴇ ᴛʜᴇ ᴛᴏɴɢᴜᴇ, ʟɪᴠᴇʀ, ᴘᴀɴᴄʀᴇᴀꜱ ᴀɴᴅ ɢᴀʟʟ ʙʟᴀᴅᴅᴇʀ.

The process of digestion involves the following steps, namely:

❶ɪɴɢᴇꜱᴛɪᴏɴ

❷ᴍɪxɪɴɢ ᴀɴᴅ ᴍᴏᴠᴇᴍᴇɴᴛ

❸ꜱᴇᴄʀᴇᴛɪᴏɴ

❹ᴅɪɢᴇꜱᴛɪᴏɴ

❺ᴀʙꜱᴏʀᴘᴛɪᴏɴ

❻ᴇxᴄʀᴇᴛɪᴏɴ

❮ ᕼOᑭE IT ᕼEᒪᑭᔕ YOᑌ❯

TᕼᗩᑎK YOᑌ