Digestive System - Anatomy and Physiology

stomach

accepts food contents from the esophagus

duodenum

the first section of the small intenstines

cecum

area of large intestines that ileum empties into

ascending colon

portion of large intenstine thta travels up the right side

descending colon

portion of large intestines that travels down on the left side

rectum

terminal part of large intestines

the rectum

terminal part of large intestines

ilieum

last portion of small intestines; joins with large intestines

pharynx

shared passawage for air and food; connects mouth with esophagus

mouth/oral cavity

entrance to the GI tract

esophagus

food tube leads to the stomach

sigmoid colon

passageway between colon and anal canal

anal canal

S-shaped portion of large intestines

transverse colon

portion of large intestines that travels across abdomen

small intestine

portion of GI tract that specializes in absorption of nutrients

mouth

portion of the GI tract where mechanical digestion begins

stomach

strongest organ of the GI tract that contains 3 layers of muscle

liver

organ that detoxifies harmful substances

pancreas

organ that produces insulin and shuttles glucose to cells

large intestine

portion of the GI tract that specializes in absorption of water.

Carbohydrates (Starch, Disaccharides)

location: mouth, small intestines

enzyme: amylase (pancreatic juice), sucrase, lactase, maltase (intestinal juice)

end product: starch=disaccharides

proteins

location: stomach, small intestines

enzyme: pepsin, trypsin (pancreatic juice), pepitdase (intestinal juice)

end product: amino acids

fats

location: small intestines

enzyme: lipase (pancreatic juice)

end product: fatty acids

villi/microvilli in the small intestine

nutrient absorption

esophagus and smooth muscle

used for transit

peristalsis

automatic, wave-like contraction of smooth muscles in the digestive tract that moves food (bolus) from the esophagus to the rectum

greater omentum

extension of the peritoneum that covers the abdominal organs; stores fat to help insulate, cushion and protect abdominal organs

pepsin

breaks down dietary proteins (meat, eggs, dairy) into smaller peptides and amino acids for absorption

bile

a bitter greenish-brown alkaline fluid that aids digestion and is secreted by the liver and stored in the gallbladder.

mesentery

attaches the organs to the wall of the abdominal cavity

chyme

a thick, semi-fluid mass of partially digested food and digestive secretions (gastric juices) formed in the stomach

peritoneum

the largest serous membrane in the body, forming a thin, continuous lining of the abdominopelvic cavity and covering most internal abdominal organs

parietal peritoneum

lines the abdominopelvic cavity

lacteal

specialized lymphatic capillaries located in the villi of the small intestine that absorb dietary fats and fat-soluble vitamins (as chyle) during digestion

mucosa

innermost layer, moister membrane that lines the cavity.

muscularis interna

a thin, continuous layer of smooth muscle that forms the deepest layer of the mucosa in the gastrointestinal (GI) tract. It separates the mucosa (lamina propria) from the underlying submucosa.

palatine tonsils

paired, oval-shaped masses of lymphoid tissue

plicae circulares

circular folds help to increase surface area for maximal absorption

rugae

prominent, highly elastic longitudinal and transverse folds of the mucosa and submucosa in the stomach, specializing in expansion and mechanical digestion

serosa

outermost layer, serious fluid-producing cells. Forms the visceral pertioneum

submucosa

just below mucosa, soft connective tissue containing nerve endings and blood vessels.

cardioesophageal sphincter

region where food enters the stomach from esophagus

fundus

most superior curved portion of the stomach

body

midportion of body

pyloric sphincter

allows small amounts of chyme into the small intestine at a time.

pylorus

terminal, funnel-shaped portion of stomach

villi

fingerlike projections of the mucosa that absorb nutrients into the blood stream via capillary bed and lacteals

microvilli

tiny projections of the plasma membrane of the mucosa cells that produce ensymes to complpete digestion

external anal sphincter

voluntary skeletal muscle; allows you to “hold” feces

internal anal sphincter

involuntary smooth muscle; when open gives you the “urge” to go

parotid gland

largest; anterior to ears

submandibular gland

floor of mouth

sublingual gland

below tongue

hepatic duct

crucial tubes that drain bile—essential for fat digestion—from the liver

pancreatic duct

transports digestive enzymes and bicarbonate from the pancreas to the duodenum

visceral peritoneum

the outer covering of the alimentary canal