Question

explain full digestion process with the video clip​

Answer 1

$\textbf{Alimentary Canal }$:

The digestive system from Oesophagus to the anus is called alimentary canal. It is about 9 metre long. It is also called food tube.

It constitutes the organs namely :

Buccal cavity, Oesophagus, Stomach, Small intestine, Large intestine, Rectum, Anus.

$\textbf{Role of mouth }$:

Humans take in food through the mouth. It is the uppermost part of alimentary canal which is bounded by lips and cheeks, and contains tongue and slaivary gland. The food taken in is chewed or groinded by teeth at the same time in the salivary glands, saliva starts to secrete which contains enzymes( $\textbf{Salivary Amylase }$ )that breaks search into sugar.

Now the tongue helps in mixing this saliva with food, it also gives taste of food also it helps in swallowing the food.

$\textbf{Role of oesophagus}$ :

It is tubular part of alimentary canal about 25cm long. It is also the narrowest part of alimentary canal. It is hollow which allows the passage of food from Buccal cavity to the stomach. During which food gets mixed with various digestive juices.

$\textbf{Role of Stomach }$

It is J-shaped bag like structure made of muscle. Here gastric glance are present which secret mucus, HCL and digestive enzymes. The function of mucus is to protect stomach lining from the action of enzymes and acid. HCL kills bacteria present in food, making the food acidic; so that enzymes can act on it. Here food stays for 4-5 hours.

$\textbf{Role of Small intestine }$:

It is located below the stomach and is coiled in appearance. This tube is abour 7.5 m long. It has three main divisons : duodenum, jejunum and ileum. Duodenum is the first part having two different ducts namely bile duct and pancreatic duct. In this tube digested food (partially) is mixed with pancreatic juice, bile juice anf other juices. Jejunum is the middle pary, found only in man. Ileum is the last part of Small intestine.

Total absorbtion takes place in the ileum. This ileum has villi on its surface. This villi increases surface area for absorbtion. The villi have blood vessels, digested food passes villi passes to there and enters the blood stream. Which then transfers to liver and then to the heart.

$\textbf{Role of Large intestine, Rectum and Anus}$:

It is about 1.5 m long organ Food from small intestine moves here. Here the most of water and salt be removed from the water by the absorbtion. This intestine allow the passage of faecal matter through the anus.

Answer 2

$hey \: here \: is \: the \: answer$

Mouth

The mouth is the beginning of the digestive tract. In fact, digestion starts here as soon as you take the first bite of a meal. Chewing breaks the food into pieces that are more easily digested, while saliva mixes with food to begin the process of breaking it down into a form your body can absorb and use.

DigestiveSystem

Throat

Also called the pharynx, the throat is the next destination for food you've eaten. From here, food travels to the esophagus or swallowing tube.

Esophagus

The esophagus is a muscular tube extending from the pharynx to the stomach. By means of a series of contractions, called peristalsis, the esophagus delivers food to the stomach. Just before the connection to the stomach there is a "zone of high pressure," called the lower esophageal sphincter; this is a "valve" meant to keep food from passing backwards into the esophagus.

Stomach

The stomach is a sac-like organ with strong muscular walls. In addition to holding the food, it's also a mixer and grinder. The stomach secretes acid and powerful enzymes that continue the process of breaking down the food. When it leaves the stomach, food is the consistency of a liquid or paste. From there the food moves to the small intestine.

Small Intestine

Made up of three segments, the duodenum, jejunum, and ileum, the small intestine is a long tube loosely coiled in the abdomen (spread out, it would be more than 20 feet long). The small intestine continues the process of breaking down food by using enzymes released by the pancreas and bile from the liver. Bile is a compound that aids in the digestion of fat and eliminates waste products from the blood. Peristalsis (contractions) is also at work in this organ, moving food through and mixing it up with digestive secretions. The duodenum is largely responsible for continuing the process of breaking down food, with the jejunum and ileum being mainly responsible for the absorption of nutrients into the bloodstream.

Three organs play a pivotal role in helping the stomach and small intestine digest food:

Pancreas

Among other functions, the oblong pancreas secretes enzymes into the small intestine. These enzymes break down protein, fat, and carbohydrates from the food we eat.

Liver

The liver has many functions, but two of its main functions within the digestive system are to make and secrete bile, and to cleanse and purify the blood coming from the small intestine containing the nutrients just absorbed.

Gallbladder

The gallbladder is a pear-shaped reservoir that sits just under the liver and stores bile. Bile is made in the liver then if it needs to be stored travels to the gallbladder through a channel called the cystic duct. During a meal, the gallbladder contracts, sending bile to the small intestine.

Once the nutrients have been absorbed and the leftover liquid has passed through the small intestine, what is left of the food you ate is handed over to the large intestine, or colon.

Colon (Large Intestine)

The colon is a 5- to 6-foot-long muscular tube that connects the cecum (the first part of the large intestine to the rectum (the last part of the large intestine). It is made up of the cecum, the ascending (right) colon, the transverse (across) colon, the descending (left) colon, and the sigmoid colon (so-called for its "S" shape; the Greek letter for S is called the sigma), which connects to the rectum.

Stool, or waste left over from the digestive process, is passed through the colon by means of peristalsis (contractions), first in a liquid state and ultimately in solid form as the water is removed from the stool. A stool is stored in the sigmoid colon until a "mass movement" empties it into the rectum once or twice a day. It normally takes about 36 hours for stool to get through the colon. The stool itself is mostly food debris and bacteria. These bacteria perform several useful functions, such as synthesizing various vitamins, processing waste products and food particles, and protecting against harmful bacteria. When the descending colon becomes full of stool, or feces, it empties its contents into the rectum to begin the process of elimination.

HOPE IT HELPS YOU!