Digestive System Study Guide: Functions, Bile Breakdown, Identification

Oral Cavity

Entry point for food where both mechanical and chemical digestion begins.

Salivary Amylase

Enzyme that begins digesting starches into simpler sugars in the oral cavity.

Mechanical Digestion

The process of physically breaking down food into smaller pieces, primarily done by teeth.

Incisor

Type of tooth used for cutting food.

Canine

Type of tooth used for tearing food.

Bicuspid (Premolar)

Type of tooth used for crushing and grinding food.

Molar

Type of tooth used for grinding food.

Parotid Gland

Salivary gland that produces serous fluid with enzymes.

Submandibular Gland

Salivary gland that produces a mix of mucous and serous fluid.

Sublingual Gland

Salivary gland that produces mainly mucous.

Tongue

Muscle that assists in mechanical digestion and positioning food for swallowing.

Palatine Tonsils

Part of the immune system; they help protect against pathogens entering through the mouth.

Esophagus

Tube that transports food to the stomach via peristalsis.

Stomach

Organ where chemical digestion of proteins begins, primarily using pepsin.

Pyloric Sphincter

Valve that controls the passage of chyme into the small intestine.

Duodenum

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

Jejunum

Middle section of the small intestine; primary site of nutrient absorption.

Ileocecal Valve

Controls the passage of contents from the small intestine to the large intestine.

Function of Large Intestine

Absorbs water and electrolytes, compacts waste.

Haustra

Pouches in the large intestine that allow for expansion and storage.

Pancreatic Amylase

Enzyme produced by the pancreas that continues carbohydrate digestion.

Bile

Substance produced by the liver to emulsify fats.

Lobule

Functional unit of the liver.

Hepatocytes

Liver cells that process nutrients and detoxify substances.

Portal Vein

Supplies nutrient-rich blood to the liver.

Brunner’s Glands

Glands in the duodenum that secrete alkaline mucus to neutralize stomach acid.

Peyer’s Patches

Lymphatic tissue in the ileum for immune defense.

Goblet Cells

Cells in the large intestine that secrete mucus.

Acinar Cells

Cells in the pancreas that produce digestive enzymes.

Central Vein of Liver

Drains blood from the lobule after filtration.

Epiglottis

Flap of cartilage that covers the windpipe during swallowing to prevent food from entering the airway.

Trachea

Airway that connects the larynx to the lungs, allowing passage of air.

Larynx

Voice box; it houses the vocal cords and is involved in breathing and sound production.

Diaphragm

Muscle that separates the thoracic cavity from the abdominal cavity and plays a crucial role in breathing.

Peristalsis

Involuntary waves of muscle contraction that move food through the digestive tract.

Chyme

Semi-fluid mass of partially digested food that leaves the stomach and enters the small intestine.

Small Intestine

The part of the digestive system where most digestion and absorption of nutrients occurs.

Large Intestine

Final section of the digestive system, responsible for water absorption and formation of feces.

Rectum

The final section of the large intestine, where feces are stored before excretion.

Anus

The opening at the end of the digestive tract through which feces leaves the body.

Liver

Organ that produces bile and processes nutrients from the digestive tract.

Gallbladder

Storage organ for bile produced by the liver.

Pancreas

Gland that produces digestive enzymes and hormones like insulin.

Villi

Small, finger-like projections in the small intestine that increase surface area for absorption.

Microvilli

Tiny projections on the surface of villi that further increase absorption area in the small intestine.

Pepsin

Enzyme in the stomach that begins the digestion of proteins.

Bicarbonate

Buffer produced by the pancreas to neutralize stomach acid in the small intestine.

Acidic Chyme

Chyme that has a low pH, rich in gastric acid, as it enters the small intestine.

Rugae

Folds in the stomach lining that allow for expansion.

Gastric Glands

Glands in the stomach that produce digestive juices and enzymes.

Intrinsic Factor

Protein produced by the stomach essential for vitamin B12 absorption.

Digestive Enzymes

Biological catalysts that speed up the chemical reactions involved in digestion.

Cholecystokinin (CCK)

Hormone secreted by the small intestine that stimulates the gallbladder to release bile.

Lacteal

Small lymphatic vessel in the villi of the small intestine that absorbs fatty acids.

Lipase

Enzyme that breaks down fats into fatty acids and glycerol.

Secretin

Hormone released by the small intestine that stimulates the pancreas to secrete bicarbonate.

Esophageal Sphincter

Muscle that controls the passage of food from the esophagus into the stomach.

Peptic Ulcer

Sore in the stomach or duodenum caused by the erosion from gastric acid.

Sodium Bicarbonate

Chemical compound produced by the pancreas that neutralizes stomach acid in the small intestine.

Intestinal Flora

Bacteria in the intestines that aid in digestion and produce certain vitamins.

Salivary Glands

Glands in the oral cavity that produce saliva,