Digestive System

List all of the main organs of the digestive system:

List all of the main organs of the digestive system:

Mouth, Pharynx, Esophagus, Stomach, Small intestine, Large intestine, Anus

List all of the accessory organs of the digestive system:

Salivary glands, Pancreas, Liver, gallbladder

Describe the 4 layers of the walls of the digestive tract and their functions. (Innermost to outer most).

Mucosa, Submucosa, Muscularis externa, Serosa

Mucosa

Innermost, moist membrane consisting of LINING tissues and cavity

Submucosa

Soft connective tissue with blood vessels, nerve endings, mucosa-associated **lymphoid tissue (**MALT), and lymphatic vessels

Muscularis externa

smooth muscle (moves things), inner circular layer and outer longitudinal layer

Serosa

outermost layer of the wall; contains fluid-producing cells

Secrets serous fluid to prevent rubbing, protective outer layer

Visceral peritoneum (Serosa)

innermost layer that is continuous with the outermost layer

Parietal peritoneum (serosa)

outermost layer that lines the abdominopelvic cavity by way of the mesentery

What types of tissue line the various organs of the GI tract?

Peritoneum ; Visceral (organs) and parietal (cavity) layer; Serous fluid inbetween

Define Secretion:

a product going out of a gland into the body/bloodstream

Define Ingestion:

placing of food into the mouth

Define Digestion:

breaking food into nutrient molecules

Define Absorption:

movement of nutrients into the bloodstream

Define Excretion:

waste/feces coming out of the body

What is salivary amylase? Where is salivary amylase produced? What is the function of salivary amylase?

an enzyme; the salivary glands;

It begins starch digestion

Segmentation:

small intestine moves food back and forth to mix with digestive juices

Peristalsis

Moving the bolus (food) towards the stomach

Mastication

chewing of food

Deglution

swallowing

mechanical digestion

The preparation of food for further degradation by enzyme ;

located in the mouth and stomach

Examples: mixing of the food by the tongue, churning of food in the stomach, small intestine moving the food back and forth

Chemical digestion

Enzymes breaking down your food

Located in the small intestine

Enzymes produced by intestinal cells and the pancreas are carried to the duodenum by pancreatic ducts

Bile, formed by the liver, enters the duodenum

esophageal hiatus

opening in the diaphragm through which the esophagus and the vagus nerve pass.

Explain the importance of the epiglottis.

Your flap to prevent food going down your trachea/windpipe

Function of the liver

It produces bile and breaks down bad substances.

Does everything basically

Structure of the liver

It is the largest gland in the body located on the right under the diaphragm, and it has 4 lobes.

Function of the pancreas

produces digestive enzymes to break down food and secretes those enzymes into the duodenum. It also produces insulin and glucagon.

Describe the pancreas:

It is a soft, pink triangular gland that is posterior to the parietal peritoneum (retroperitoneal).

Function of the gallbladder?

It stores and concentrates bile from the liver.

Describe the gallbladder:

It is a green sac found in a shallow fossa below the liver.

What is the function of the large intestine?

Nutrient breakdown and absorption

Absorbs water

No digestive enzymes are produced

Indigestible food is delivered to the body’s exterior as feces

What are the 4 different regions of the stomach?

Cardial, Fundus, Body, Pylorus

Where in the stomach is the Cardial region located?

It is near the heart, and it surrounds the cardio esophageal sphincter

Where in the stomach is the Fundus region located?

expanded portion lateral to the cardiac region

Where in the stomach is the Body region located?

Midportion

What is the Pylorus region of the stomach?

Funnel-shaped terminal end that empties into the small intestine

Which major layer of the stomach contains an extra layer that adds strength and aids in the formation of chyme?

The muscularis externa

What are the 3 types of cells in the gastric glands?

Chief cells, parietal cells, mucous cells

What is the function of chief cells?

They produce protein-digesting enzymes (pepsinogens)

What is the function of parietal cells?

They produce hydrochloric acid that activates enzymes

What is the function of mucous cells?

They produce thin acidic mucus

What are rugae? What is the function of rugae?

internal folds of the mucosa present when the stomach is empty

They increase the surface area of the stomach and stretch out to increase stomach volume when the stomach is full

Name the 3 parts of the small intestine:

duodenum, jejunum, ileum

function of the duodenum?

Absorption of vitamins, minerals, and other nutrients. Enzymes are secreted into it.

What is the function of the Jejunum?

It further digests food coming from the stomach and absorbs nutrients from food.

What is the function of the Ileum?

It absorbs any remaining nutrients from food, so they can be used by the body.

Where does most nutrient absorption take place?

the small intestine