Chapter 25, Lesson 3: The Stomach (up to slide 85)

Flashcards from Chapter 25, Lesson 3 of McGraw Hill Anatomy and Physiology, Tenth Edition, by Kenneth S. Saladin.

Stomach

A J-shaped, muscular sac in the upper left abdominal cavity that functions as a food storage organ for mechanical and chemical digestion

Chyme

The acidic, soupy mixture of semidigested food that passes on to the small intestine

Cardiac part

A small area within about 3 cm of the cardiac orifice; connects esophagus to stomach

Fundic region (fundus)

Dome superior to the esophageal attachmenet

Body

The greatest part of the stomach distal to the cardiac orifice

Pylorus

The narrow passage from the stomach to the duodenum

Pyloric sphincter

A ring of smooth muscle around the pylorus that regulates the passage of chyme into the duodenum

Greater curvature

40 cm curvature from which the greater omentum hangs

Lesser curvature

10 cm curvature from which the lesser omentum has

Gastric rugae

Longitudinal wrinkles that allow for expansion; contracts when empty

Gastric pits

Depressions in the gastric mucosa with two or three tubular glands at the bottom; secretes substances

Mucous cells

Cells that secrete mucus in the cardiac and pyloric glands (called mucous neck cells in gastric glands due to their position)

Regenerative cells (stem cells)

Cells found in the base of the gastric pit and neck of the glands; divides rapidly and produces a continual supply of new cells for replenishment

Parietal cells

Cells found mostly in the upper half of the glands; secretes hydrochloric acid, intrinsic factor, and a hunger hormone called ghrelin

Chief cells

The most numerous cell type in the stomach; secretes gastric lipase and pepsinogen in the gastric glands to dissolve lipids and proteins

Enteroendocrine cells

Cells concentrated in the lower end of the glands that secrete hormones and messengers to regulate digestion

Gastric juice

The 2 to 3 liters of juice produced by the gastric glands per day; mainly a mixture of water, hydrochloric acid, and pepsin

Hydrochloric acid (HCl)

Acid that activates pepsin and lingual lipase while breaking up connective tissues and plant cell walls for liquification and chyme formation; also destroys pathogens

Pepsinogen

Enzyme that is secreted by chief cells to digest proteins

Gastric lipase

Enzyme that digests about 10 to 15% of dietary fats in the stomach (the rest is digested in the small intestine)

Intrinsic factor

A glycoprotein secreted by parietal cells; helps absorb vitamin B₁₂ in the small intestine to later synthesize hemoglobin — secretion of this is the only indispensable function of the stomach

Swallowing center

Part of the medulla oblongata that signals the stomach to relax during swallowing; controls chyme flow to 3 mL