Bio exam 4

anal sphincter

A group of muscles at the end of the rectum that controls the release of feces and gas from the body, playing a vital role in bowel control.

bicarbonate

A vital buffer in the digestive system that helps neutralize stomach acid in the small intestine, facilitating enzyme function.

bile

A digestive fluid produced by the liver that aids in the emulsification and absorption of fats in the small intestine.

bile duct

The tube that carries bile from the liver and gallbladder to the duodenum, aiding in the digestion of fats.

bolus

A mass of food that has been chewed and mixed with saliva, forming a cohesive lump that can be swallowed.

cardiac sphincter

A muscular ring at the junction of the esophagus and stomach that regulates the passage of food and prevents reflux.

CCK

A hormone that stimulates the digestion of fat and protein and is released by the small intestine.

Chemical digestion

The process by which food is broken down into smaller, absorbable components in the digestive system, often involving enzymes and acids.

cholecystokinin

A hormone secreted by the small intestine that stimulates the gallbladder to release bile and the pancreas to produce digestive enzymes.

chyme

The semi-liquid mixture of partially digested food and digestive juices that is expelled from the stomach into the duodenum.

defecation

The process of eliminating waste from the digestive tract through the anus.

denature

To alter the natural structure of proteins, often due to heat or pH changes, resulting in loss of function.

digestion

The process of breaking down food into smaller components that can be absorbed and utilized by the body.

duodenum

the first section of the small intestine where most chemical digestion occurs.

E. coli

a bacterium often found in the intestines, some strains of which can cause food poisoning.

esophagus

A muscular tube connecting the throat to the stomach, facilitating the passage of food.

gall bladder

A small organ that stores bile produced by the liver, aiding in the digestion of fats.

gastric secretions

Fluid produced by the stomach that aids in digestion, including enzymes, acid, and mucus.

gastrin

A hormone secreted by the stomach that stimulates the secretion of gastric acid and aids in digestion.

gastrin inhibitory peptide

A hormone that inhibits gastric acid secretion and stimulates insulin release after eating.

GIP

A hormone that plays a role in digestion by inhibiting gastric acid secretion and promoting insulin release after the intake of food.

HCI

A strong acid produced in the stomach that aids digestion by breaking down food and activating digestive enzymes.

Hormone

that regulates gastric functions and glucose metabolism.

Hydrochloric acid

a strong acid produced in the stomach that aids in digestion and creates an acidic environment for enzymes to function.

ileum

The final section of the small intestine, where most nutrient absorption occurs.

ingestion

The process of taking in food and drink through the mouth.

jejunum

The middle section of the small intestine, located between the duodenum and ileum, primarily responsible for the absorption of nutrients.

large intestine

The last section of the gastrointestinal tract, responsible for absorbing water and electrolytes, and forming and storing feces.

liver

An organ that produces bile, processes nutrients, and detoxifies harmful substances.

mechanical digestion

The process of breaking down food into smaller pieces through physical means, such as chewing and stomach churning, without altering the chemical structure.

mouth

The first part of the digestive system where food enters, and mechanical digestion begins with chewing.

mucus

A viscous secretion that protects and lubricates mucous membranes in the digestive system.

pancreas

An organ that secretes digestive enzymes and hormones such as insulin, playing a crucial role in regulating blood sugar and aiding digestion.

pancreatic duct

A tube that carries digestive enzymes from the pancreas to the small intestine.

pancreatic juice

A digestive fluid produced by the pancreas that contains enzymes and bicarbonate to aid in digestion.

pepsin

An enzyme in gastric juice that digests proteins into peptides. It is secreted by the stomach lining in its inactive form, pepsinogen, which is activated by stomach acid.

pepsinogen

An inactive precursor of pepsin, secreted by the stomach's chief cells, which is converted to pepsin in the presence of gastric acid.

peristalsis

The rhythmic contraction of smooth muscle in the digestive tract that moves food along the gastrointestinal system.

peristaltic contractions

are waves of smooth muscle contractions that move food through the digestive tract.

pyloric sphincter

A muscular valve that controls the flow of partially digested food from the stomach into the small intestine.

salivary glands

Glands in the mouth that produce saliva, aiding in digestion and lubrication of food.

secretin

A hormone produced by the duodenum that stimulates the pancreas to release bicarbonate, helping to neutralize stomach acid in the small intestine.

small intestine

The part of the gastrointestinal tract that follows the stomach, where most digestion and nutrient absorption occurs.

sphincter

A ring-like muscle that controls the passage of substances between different sections of the digestive tract by opening and closing.

stomach

Muscular organ that digests food and mixes it with gastric juices.

villi

Finger-like projections in the small intestine that increase surface area for nutrient absorption.