Question

need to know a,b,c

A. list and describe in general terms the anatomy and function of the organs and accessory organs of the digestive system.

B. identify: ingestion, propulsion, mechanical digestion, chemical digestion, absorption, defecation.

C. list the importance of vitamins and minerals in the diet

Answer 1

Answers---

A - anatomy and functions of the organs and accessory organs of the digestive system.

Digestive system is one of the most important system which is involved in the digestion of the food we take in body and helpful in the assimilation of the important nutrient in the cell.

There are various organs which work together from the mouth to the rectum which involved in the digestion of fat , protein , carbohydrate etc in the body according to the functions.

There are major organs and are some accessory organs which do involved in the process of digestion.

These are;

• salivary glands
• pharynx
• oesophagus
• stomach
• small intestine ( duodenum , jejunum , ileum )
• large intestine ( caecum , colon , rectum , external orifice)
• liver
• gall bladder
• pancreas

These are the organs which are the part of the digestive system ( Liver gallbladder and pancreas are accessory digestive organs)

ANATOMY OF DIGESTIVE ORGANS

Digestive system which is whole alimentary canal consist of special cells called epithelium layers the whole alimentary canal in four layers called mucosa submucosa , muscularis externa and serosa.

Layers of the Alimentary Canal

Now the most innermost layer is mucosa which has a special eoithelial cells called lamina propia and they carry nerves , blood vessels glands etc.

And is the are of mouth and oesophagus there is stratified squamous and simple columnar near the stomach and intestine.

The second layer is sub mucosa that carry the fat , fibrous tissue and larger nerve.

More external to this is muscularis externa while external layer that is made up of fat is called serosa

Oral Cavity :- oral cavity is the external connection responible for the intake of the food which has stratified squamous mucosa and consist of the teeth , palate tongue etc which is responsible for chewing and mastification of the food,

Salivary glands are situated in the mouth and they use to secrete enzyme amylase and lingual lipase and involved in the digestion of carbohydrate and fat; parotid gland are largest salivary gland size is about 3.6cm. and other two are submandibular and sub lingual gland.

Salivary glands have some secretory acinar cells that secrete there content into the ducts which are special ducts.

saliva makes food soft and makes food into the bolus and then it goes in oesophagus via pharynx.

Oesophagus is the hollow cylindrical muscular tube which connects the mouth to the stomach and food goes here and digestion. which is 25cm long and 2cm diameter.

It has inner circular and outer longituginal muscles arranged supports the peritalsis.

From the oesophagus food is transferred to the small intestine for further assimilation of the nutrient and there also digestion of elements occurs.

Stomach It is the j shaped bag like structure located in the abdominal cavity slight left to the mid line and in the center of the oesophagus and intestine and on a average considering it has 6 inches of size and has 4 parts and 2 curvatures.

2 curvature are greater curvature and lesser curvauture and 4 parts are cardia which is the first part where the oesophagus contacts the stomach , next is the fundus which the second part which is dome shaped near the diaphragm and next is the body which is the main part which fills the food and water and next is the pylorus which is for the transfering junction food to intestine.

After the digestion is small intestine food goes into the karge intestine where the differentiation of waste part occurs and undigested or stool part gets stored in the rectum and then excreted by the external orifice organ.

Small Intestine It is the part after the stomach which is approximate 6 meter in length and it has three parts called duodenum , jejunum and illeum. It is majorly involved in the digestion and assimilation and has numerous folds and occupies the major portion of the abdomen.

It carries the brush border appereance , microvilli that helps in secretion and absorption part.

Large Intestine It is the extension of the small intestine with the length of about 1.5m and diameter 7.5 cm and it has some parts they are appendix , caecum , colon ( ascending , descending and transverse ) rectum and sigmoid colon in which these final process the food and waste material is seprated , rectum is 15cm which recieves the waste or faecal material and then expelled out of the body

Liver gall bladder and pancreas are the organs which a very vital role in digestion all the enzymes and chemical constituents which is needed in food digestion are provided by them.

(Liver 10.5cm in size and 1500gm wieight) which is situated in right hypochondriac region of the body and has two lobes which is right lobe and left lobe and two more lobes caudate and quadrate lobes are also present.

It has major functions in digestion as it secreted important enzymes in the intestine helps in digestion and assimilation.

Gall Bladder;- it is the small pear shaped organ present in the posterior surface of the right lobe of the liver and it is 8cm long and about 2.5cm wide which has function of storage and secretion of the bile in the duodenum and has neck body and fundus as the three part.

bile is secreted from liver and stored in the gall bladder and then through duct taken to small intestine and digestion occurs

Pancreas:- It is the 15cm long organ which is present behind the stomach and its head also connects with duedenum and has long slender body , a head and a tail which is both exocrine and endocrine useful in secreting the hormones and enzymes helpful and digestion.

Pancreas also secrete digestive enzymes and take part in digestion.

B - phases of the digestion

The process of digestion have 6 main parts and these are

• Ingestion of the food by mouth
• Propulsion also we can say peristalsis movement
• Digestion ( physical and mechanical )
• Chemical digestion
• Absoprtion
• Defecation

These are the 6 process which are under the digestion process in which

Ingestion is the process of taking the food inside the body by the mouth which is the first process. where many enzymatic and digestive activity occurs and food is made soft with the help of saliva in the form of bolus and chewed with teeths.

propulsion is the process of making food move towards the oesophagus and it is the voluntary process.

After this peristalsis process occurs and then the digestion which is physical and mechanical occurs and then chemical digestion in which all process of the enzymatic activity occurs and all digestion occurs.

Digestion occurs in the stomach and the small intestine where all the largd molecules are broken down in simpler one and then are digested into the body.

Absorption is the phase of the digestion in which the nutrient which are made are goes from the alimentary canal in the blood and there they goes for the energy production and this is also called assimilation.

Defecation is the last stage of the digestion in which the waste material or undigested food is removed from the body in the form of the stool through this process.

Digestion is the broad term for the digestion of the food which have these process in it.

Secretion is the term used to show that any cell producing is called its secretion.

Answer C

​​​​​​Importance of minerals and vitamins in diet.

Vitamins and minerals are the important part of the diet which performs the various functions is the body.

Vitamins are the organic molecules which are of two types :

• Fat soluble vitamins
• Water soluble vitamins

In which fat soluble are the A , D , E AND K

and water soluble are vitamin B and C.

The vitamins are very important for diet they convert food into energy and some functions are.

• They are helpful in maintaining health
• To prevent various diseases like beri-beri muscle weakness , pellagera , night blindness , scurvy etc.
• They are helpful in regulating the repairing of the cells.
• They also delays the ageing process means maintains the ageing process
• They also used to processing large molecule and make energy from them

These were the some functions of vitamins and so they should be in diet because they are required to the body.

Minerals are also the important part of the diet which performs various functions like

• They converts food into energy
• Maintains the fluid balance in body
• They makes the bones and joints strong.
• They are helpful in membrane and signalling

TheSe were the functions of the minerals and so.they are important in diet.

Thanks you good wishes please do upote and comment if any doubt.