Digestive System Anatomy and Physiology

Vocabulary flashcards covering the structures and functions of the human digestive system as described in the lecture notes.

Mouth

The first structure that begins the digestive tract, responsible for both mechanical and chemical digestion of food.

Bolus

A food ball formed when saliva mixes with food in the mouth.

Tongue

An organ that functions in taste and in moving, mixing, and positioning food for chewing and swallowing.

Teeth

Structures that cut and crush food to increase surface area and facilitate mixing with saliva.

Salivary glands

Glands that produce and release saliva into the mouth to moisten and soften food for carbohydrate digestion.

Salivary amylase

An enzyme found in saliva that begins the hydrolysis of starch into maltose sugar.

Pharynx

Also known as the throat, this passageway allows for the food bolus to reach the esophagus and for air to enter the trachea.

Epiglottis

A structure that meets with the glottis during swallowing to cover the opening to the trachea and direct food into the esophagus.

Esophagus

A food tube about $25\,cm$ long that moves the bolus from the pharynx to the stomach.

Peristalsis

The smooth muscle contractions of the esophagus used to push food downward to the stomach.

Cardiac sphincter

A ring of muscles located at the entrance to the stomach that keeps acid chyme inside and prevents reflux.

Stomach

A muscular organ that performs mechanical and chemical digestion, produces hydrochloric acid, and activates pepsinogen.

Pepsinogen

A substance in the stomach that, when activated by low pH, helps digest proteins into peptides.

Pyloric sphincter

A muscle that controls the amount of acid chyme entering the duodenum by releasing small quantities at regular intervals.

Duodenum

The first part of the small intestine that continues digestion, neutralizes stomach acid, and uses bile to digest fats.

Gall bladder

An organ that stores bile for the emulsification of fats and lipids.

Pancreas

An organ that produces pancreatic juice with digestive enzymes and sodium bicarbonate to neutralize acid chyme.

Sodium bicarbonate

A substance contained in pancreatic juice that neutralizes acid chyme entering the small intestine.

Exocrine (Pancreas)

The function of the pancreas that involves secreting digestive juices through the pancreatic duct.

Endocrine (Pancreas)

The function of the pancreas that involves secreting insulin and glucagon into the bloodstream.

Small intestine

An organ essential for the chemical digestion and absorption of nutrients, including carbohydrates, proteins, and fats.

Appendix

A projection of the cecum located at the entrance to the large intestine that may play a role in immune function.

Large intestine

Also known as the colon; it is responsible for the absorption of water and the production of vitamins.

Rectum

The part of the digestive tract that functions in the storage of feces and defecation.

Anus

A sphincter involved in the defecation reflex.