Digestive system

It dissolves food and helps produce taste to initiate digestion.

In the floor of the mouth, below the lower jaw.

A tubular system that extends from the mouth to the anus.

They activate salivary amylase, which starts the breakdown of starch.

It prevents microbes from entering or attaching to epithelial cells.

In the cheeks, palates, tongue, and lips.

The process of eliminating wastes, indigestible substances, and digested materials that were not absorbed through the anus.

Crown.

Protection.

The upper esophageal sphincter consists of skeletal muscle, while the lower esophageal sphincter consists of smooth muscle.

99.5% water and 0.5% solutes.

Increases the surface area of the stomach and small intestine to enhance digestion and absorption.

Beneath the tongue and superior to the submandibular glands.

A protective and connective tissue that forms the outer layer of the gastrointestinal tract.

Taking foods and liquids into the mouth.

The capability of the GI tract to mix and move material along its length through alternating contractions and relaxations of smooth muscle.

Extrinsic muscles and intrinsic muscles.

Mucus and fluid containing the enzyme lingual lipase.

Blood vessels, nerves, and lymphatic vessels.

It dissolves small food molecules and contains enzymes.

A progression of coordinated contractions and relaxations of the muscularis that pushes the bolus toward the stomach.

Mucosa.

Three pairs.

It lubricates and moistens food for easy swallowing.

The tongue is composed of skeletal muscle covered with mucous membrane; it helps taste, swallow food, and speak.

Palatine and maxillae bones covered with mucous membrane.

25 cm long.

It is needed for the absorption of vitamin B12.

Gastrin.

A 1-3 mm thick layer of alkaline mucus.

It produces carbonic acid from CO2 and H2O, which dissociates into H+ and HCO3-.

Water, salts, sodium bicarbonate, and several enzymes.

Into two lobes: the right lobe (larger) and the left lobe (smaller), separated by the falciform ligament.

To store and concentrate bile.

They aid in emulsification and absorption of lipids.

The pH of the stomach chyme.

Mucosa, submucosa, muscularis, and serosa.

Wastes.

Many blood and lymphatic vessels.

Into the oral cavity lateral to the lingual frenulum.

They assist in digestion but do not come into direct contact with food; they produce secretions that aid in chemical breakdown.

Structures that cover the upper and lateral surfaces of the tongue, many of which contain taste buds.

They provide sensation.

The upper esophageal sphincter (UES).

The last tapering portion of the pancreas.

Insulin.

It is a starch-digesting enzyme.

Water, bile salts, cholesterol, lecithin, bile pigments, and several ions.

It plays a major role in digestion and absorption of nutrients.

Folds of mucosa and submucosa that increase surface area and facilitate the movement of chime.

Alkaline mucus that helps neutralize gastric acid in the chyme.

By simple diffusion.

Water-soluble vitamins B and C.

Anal canal.

Protection, secretion, and absorption.

Areolar connective tissue.

It destroys harmful bacteria.

The largest serous membrane in the body.

Through the cutting and grinding of food by teeth and the mixing by smooth muscles in the stomach and small intestine.

They bring nourishment.

Bolus.

The secretion of saliva and mucus.

In the acidic environment of the stomach.

It helps in respiration.

Pancreatic juice, a mixture of fluid and digestive enzymes.

Somatostatin secretion.

Head, Body, and Tail.

Trypsin, Chymotrypsin, Carboxypeptidase, and Elastase.

By the absorption of water and ions.

By breaking down glycogen to glucose and converting lactic acid and amino acids into glucose.

The liver, along with skin and kidneys, participates in synthesizing the active form of vitamin D.

At the pyloric sphincter of the stomach.

Mucus.

Fingerlike projections of mucosa that vastly increase surface area for absorption and digestion.

Epithelium, lamina propria, and muscularis mucosae.

The digestive system.

Both skeletal muscles and smooth muscles.

Mechanical digestion and chemical digestion.

Gingivae (gums).

Cementum.

Pepsinogen and gastric lipase.

Monosaccharides and disaccharides.

The stomach.

Cardia, fundus, body, and pylorus.

Large folds in the mucosa that can be seen with the unaided eye when the stomach is empty.

Areolar connective tissue.

Acini.

Gastrin, Acetylcholine, and Histamine.

Near the curve of the duodenum.

Fundus (inferior broad portion), body (middle portion), and neck (upper taper portion).

7.6 – 8.6.

Duodenum, jejunum, and ileum.

The serosa (or visceral peritoneum).

To keep mucous membranes moist, cleanse the mouth and teeth, lubricate, dissolve, and begin the chemical breakdown of food.

6.35 - 6.85; phosphate and bicarbonate ions buffer acidic food.

A bundle of neurons present in the muscularis layer.

Cheeks.

The entrance of ingested and secreted fluids, ions, and products of digestion into the epithelial cells lining the GI tract.

Dentin.

Calcium phosphate and calcium carbonate.

To cut, tear, and pulverize solid food into smaller particles for easier swallowing and digestion.

Apical foramen.

To secrete mucus and transport food into the stomach.

Chyme.

It is secreted in an inactive form called pepsinogen.

It carries pancreatic juices into the duodenum and combines with the common bile duct to form the hepatopancreatic ampulla.

Glucagon.

It is a retroperitoneal gland located posterior to the greater curvature of the stomach.

Inferior to the diaphragm.

Bile canaliculi → bile ductules → left/right hepatic ducts → common hepatic duct → cystic duct → common bile duct.

It is converted into glycogen and triglycerides for storage.

They digest and absorb nutrients.

Contains blood and lymphatic vessels that transfer absorbed nutrients and contains immune system cells.

An extensive network of neurons that is part of the enteric nervous system (ENS).

Parietal peritoneum and visceral peritoneum.

Crown, root, and neck.

They alter the shape and size of the tongue for speech and swallowing.

Starts from the inferior end of the laryngopharynx and ends at the superior portion of the stomach.

Gastric glands.

The act of swallowing.

No, it does not produce digestive enzymes.

Gastric emptying.

Gastric lipase.

It is formed by the combination of the pancreatic duct and the common bile duct, opening into the duodenum.

Lobule.

Contraction of smooth muscles.

They store triglycerides, break down fatty acids for ATP, synthesize lipoproteins, and produce bile salts from cholesterol.

Absorptive cells, Goblet cells, Paneth cells, and Endocrine cells.

As monosaccharides.

Nucleosidases and phosphatases.

The appendix or vermiform appendix.

Mucosa, Submucosa, Muscularis, and Serosa.

Chloride ions, sodium, potassium, bicarbonate, and phosphate ions.

To secrete saliva into the oral cavity opposite the second maxillary molar tooth.

Salivation.

The release of about 7 liters of water, acid, buffers, and enzymes into the GI tract to aid digestion.

A fold of mucous membrane that controls the posterior movement of the tongue.

To transfer the bolus from the mouth to the stomach.

Mucus.

Salivary amylase.

A 'J' shape.

It is converted into liquid.

In the mucous of the pyloric antrum.

Pepsin.

99%.

They actively transport H+ into the lumen and bring K+ back into the cell.

It is left and superior to the head.

It makes pancreatic juice slightly alkaline (pH 7.1 - 8.2) and stops the action of pepsin from the stomach.

Ribonuclease and deoxyribonuclease.

Bile.

About 1 liter.

Stellate reticuloendothelial (Kupffer) cells.

Bilirubin is derived from aged red blood cells and is absorbed by the liver to be secreted into bile, where it is metabolized in the small intestine.

Secretin, cholecystokinin (CCK), and glucose-dependent insulinotropic peptide (GIP).

They have digestive functions and are located on the brush border formed by microvilli.

Secondary active transport.

Segmentation and Migrating Motility Complex (MMC).

Cecum, colon, rectum, and anal canal.

It splits maltose and maltriose into 2-3 units of glucose.

To release saliva into the oral cavity.

Near the ears.

They help in voluntary swallowing and defecation.

A continuous tube extending from the mouth to the anus, including organs like the mouth, pharynx, esophagus, stomach, small intestine, and large intestine.

Oral cavity or Buccal cavity.

It prevents the entrance of swallowed food and liquid into the nasal cavity.

Pulp cavity.

Chewing or mastication by teeth.

It breaks down triglycerides into diglycerides and fatty acids.

Nasopharynx, oropharynx, and laryngopharynx.

It regulates communication between the stomach and the duodenum.

Mixing waves.

Serosa.

It is 12-15 cm long and 2-3 cm thick.

The liver stores glycogen, certain vitamins (A, B12, D, E, and K), and minerals (iron and copper).

At the ileocecal junction of the large intestine.

Outer longitudinal and inner circular muscles.

Micelles.

From the ileum to the anus.

Pancreatic amylase and brush border enzymes.

Ribonuclease (digests RNA) and deoxyribonuclease (digests DNA).

Villi and circular folds.

A strong peristaltic wave that drives colonic contents into the rectum.

Gastrin secretion stops.

Excessive production of gases by bacteria.

90%.

The forcible expulsion of contents from the upper GI tract through the mouth.

Sexual contact and contaminated syringes.

The gastrointestinal (GI) tract and the accessory digestive organs.

They move the tongue from side to side and in and out to maneuver food for chewing and swallowing.

Enamel.

Mucosa, submucosa, muscularis, and serosa.

In the alveolar processes of the mandible and maxillae.

1. Voluntary stage, 2) Pharyngeal stage, 3) Esophageal stage.

Mixing chamber, holding reservoir for food, and initiating digestion.

They help in respiration and swallowing of food.

Gastric juice (2 – 3 liters per day).

Hydrochloric acid (HCl).

The pancreatic duct is larger in size, while the accessory duct is smaller.

Kupffer cells.

Simple epithelial cells.

It extends up to 25 cm.

7.6.

Completion of absorption, production of certain vitamins, formation of feces, and expulsion of feces from the body.

3 to 5 hours.

By simple diffusion through micelle formation.

Pouches formed by the tonic contraction of circular muscles.

Vitamin B and K.

Ulcers that develop in areas of the GI tract exposed to acidic gastric juice.

They produce intrinsic factor and hydrochloric acid.

A funnel-shaped tube covered with mucous and composed of skeletal muscle.

The concave medial border is the lesser curvature, and the convex lateral border is the greater curvature.

Oblique muscles, circular muscles, and longitudinal muscles.

Water, ions, short-chain fatty acids, certain drugs (like aspirin), and alcohol.

Pancreatic Islets or Islet of Langerhans.

1200 - 1500 ml.

Pancreatic lipase.

The small intestine is composed of four basic layers.

Lysozyme, which has a bactericidal function.

About 1 - 2 liters.

Na+, Ca2+, bicarbonate, chloride, iodide, nitrate.

It acts on α-dextrin to produce glucose.

Triglycerides are broken into fatty acids and monoglycerides by pancreatic lipase, and bile salts emulsify long chain fatty acids.

Food entering the small intestine.

Secretion of pancreatic juice and contraction of the gallbladder.

Irritation of the esophageal wall by hydrochloric acid (HCl) from stomach contents.

A yellowish coloration of the sclerae, skin, and mucous membranes due to a buildup of bilirubin.

Lingual lipase.

Pancreatic duct and accessory duct.

H+ and Cl- separately, resulting in the secretion of HCl.

It maintains glucagon and insulin levels in the body.

Hepatocytes.

By removing the amino group to produce ATP or convert them into carbohydrates or fats, and converting harmful amino groups into urea.

Alcohol and various drugs such as penicillin and erythromycin.

Projections from the free membrane of absorptive cells that form a brush border.

90%.

Aminopeptidase and dipeptidase.

Ileocecal sphincter.

By active or passive transport.

It combines with intrinsic factor produced by the stomach and is absorbed in the ileum via active transport.

The absorption of electrolytes and nutrients to maintain osmotic balance with the blood.

Cholecystokinin (CCK) and secretin.

A condition where stomach contents reflux into the esophagus due to inadequate closure of the lower esophageal sphincter.

They are used for emulsification and absorption of lipids.

Pentoses, phosphates, and nitrogenous bases.

Carbohydrate-digesting enzymes, protein-digesting enzymes, and nucleotide-digesting enzymes.

Localized mixing contractions that help in mixing and absorption of chyme without pushing it forward.

Trypsin, chymotrypsin, carboxypeptidase, and elastase.

All water absorption occurs via osmosis.

Absorptive and goblet cells.

Hydrogen, CO2, and methane gas.

It slows the exit of chyme from the stomach.

Cephalic phase, gastric phase, and intestinal phase.

It produces urease, which damages the protective mucous layer of the stomach.

Prehepatic, hepatic, and extrahepatic jaundice.

Absorption.

α-dextrinase, maltase, sucrase, and lactase.

A small pouch-like organ next to the ileocecal sphincter.

Mucus that lubricates the passage of colonic contents.

It consists of circular and longitudinal muscles that aid in movement.

3 to 4 times a day.

Food distending the stomach.

Stercobilin, which gives brown color to fecal material.

Neural and hormonal mechanisms regulate gastric secretion and motility.

Irritation and distension of the stomach, unpleasant sights, general anesthesia, dizziness, and certain drugs.

Cigarette smoke, alcohol, caffeine, and NSAIDs.

Insufficient bile salts or lecithin or excessive cholesterol in bile.

Clinically similar and can also cause cirrhosis and liver cancer.

Digestion.

It mixes with pancreatic juices and provides a liquid medium for absorption from chyme into the small intestine.

About 1.5 meters.

Into ascending colon, transverse colon, descending colon, and sigmoid colon.

Water absorption.

Hustra remain relaxed and distend when filled, then contract to move contents.

Bacteria ferment remaining carbohydrates and convert proteins to amino acids and simpler substances.

Water, inorganic salts, sloughed-off epithelial cells, bacteria, products of bacterial decomposition, unabsorbed digested materials, and indigestible parts of food.

1. Helicobacter pylori, 2) NSAIDs, 3) Hypersecretion of HCl.

Loss of appetite, malaise, nausea, diarrhea, fever, and chills.

They carry fatty acids and monoglycerides to absorptive cells and help solubilize other large hydrophobic molecules.

It is a type of peristaltic movement that pushes chyme forward when the volume in the small intestine decreases.

About 20 cm.

Internal sphincter of smooth muscles and external sphincter of skeletal muscles.

Enterogastric reflex.

Secretin buffers acid in chyme that reaches the duodenum and slows acid production in the stomach.

Via fecal contamination of objects (fecal-oral route).

Cirrhosis and possibly liver cancer.

Stimulates gastric glands to secrete gastric juice.

Flow of pancreatic juice rich in bicarbonate ions.

Drinking alcohol and smoking.

It converts toxic substances like indole and hydrogen sulfide into less toxic substances.

Smell, sight, thought, or initial taste of food.

3 to 10 hours.

Bleeding, which can lead to anemia.

An inflammation of the liver caused by viruses, drugs, and chemicals.

Water, vitamins, and minerals.

To break down food into forms that can be absorbed and used by body cells.