Human Digestion and Enzymatic Functions

<p>Mucus (A)</p> Signup and view all the answers

<p>It increases the secretion of mucus and HCO3–. (B)</p> Signup and view all the answers

<p>To break down food into usable substances (C)</p> Signup and view all the answers

<p>Salivary amylase (A)</p> Signup and view all the answers

<p>They should reach the bloodstream (D)</p> Signup and view all the answers

<p>Digested food molecules do not reach the bloodstream (D)</p> Signup and view all the answers

<p>Polysaccharides (B)</p> Signup and view all the answers

<p>Starch (B)</p> Signup and view all the answers

<p>Absorption (B)</p> Signup and view all the answers

<p>It initiates carbohydrate digestion (C)</p> Signup and view all the answers

<p>The Gastric Phase primarily involves chyme entering the stomach, while the Intestinal Phase involves chyme entering the small intestine. (B), The Gastric Phase is stimulated by local nervous reflexes and gastrin, while the Intestinal Phase is inhibited by secretin and other intestinal hormones. (D)</p> Signup and view all the answers

<p>To slow down gastric emptying when the small intestine is full and/or irritated. (B)</p> Signup and view all the answers

<p>Gastrin (A)</p> Signup and view all the answers

<p>It activates the inactive enzyme trypsinogen into its active form, trypsin. (A)</p> Signup and view all the answers

<p>Breaking down starch, glycogen, and other carbohydrates into disaccharides and trisaccharides. (C)</p> Signup and view all the answers

<p>They neutralize the acidic chyme entering the duodenum from the stomach. (B)</p> Signup and view all the answers

<p>Increased HCl production triggers the 'Reverse Enterogastric Reflex' to slow down gastric emptying. (B)</p> Signup and view all the answers

<p>The arrival of acidic chyme into the duodenum, irritating the intestinal lining. (A)</p> Signup and view all the answers

<p>Enterochromaffin-like (ECL) cells (C)</p> Signup and view all the answers

<p>It splits peptides into individual amino acids. (B)</p> Signup and view all the answers

<p>Gastric secretion is primarily limited to mucus, with minimal pepsinogen and almost no acid. (D)</p> Signup and view all the answers

<p>It acts as a prebiotic in the colon, promoting the growth of beneficial bacteria. (B)</p> Signup and view all the answers

<p>Pancreatic lipase (A)</p> Signup and view all the answers

<p>Hydrolyzing cholesterol esters into cholesterol and fatty acids. (D)</p> Signup and view all the answers

<p>Both the exocrine and endocrine functions contribute to digestion, but the exocrine function is responsible for digestive enzyme secretion, while the endocrine function secretes hormones that regulate glucose metabolism. (A)</p> Signup and view all the answers

<p>The presence of acidic chyme in the duodenum (A)</p> Signup and view all the answers

<p>They transport lipids into enterocytes. (D)</p> Signup and view all the answers

<p>Excretion of undigested fats in stool. (D)</p> Signup and view all the answers

<p>They enter the blood circulation directly through capillaries. (D)</p> Signup and view all the answers

<p>They combine to form triglycerides. (B)</p> Signup and view all the answers

<p>It inhibits lipase activity. (A)</p> Signup and view all the answers

<p>In the duodenum. (D)</p> Signup and view all the answers

<p>By forming micelles with lipids. (C)</p> Signup and view all the answers

<p>Inhibition of lipase activity. (C)</p> Signup and view all the answers

<p>Pancreatic Amylase (B)</p> Signup and view all the answers

<p>Glucose and Fructose (D)</p> Signup and view all the answers

<p>Buccal Cavity (D)</p> Signup and view all the answers

<p>Galactose and Glucose (B)</p> Signup and view all the answers

<p>Digest disaccharides into monosaccharides (D)</p> Signup and view all the answers

<p>No carbohydrate digestion occurs (B)</p> Signup and view all the answers

<p>Monosaccharides (B)</p> Signup and view all the answers

<p>Pancreatic Amylase (D)</p> Signup and view all the answers

<p>Polymers with 2-3 glucose molecules (D)</p> Signup and view all the answers

<p>Maltase (B)</p> Signup and view all the answers

<p>By diffusion along an electrical gradient (C)</p> Signup and view all the answers

<p>It is secreted to maintain electrical neutrality (D)</p> Signup and view all the answers

<p>Calcium, potassium, magnesium, and phosphate (D)</p> Signup and view all the answers

<p>The body's need for hemoglobin formation (A)</p> Signup and view all the answers

<p>Diffusion through chloride channels (B)</p> Signup and view all the answers

<p>A negative charge is lost requiring another negative charge to be brought in (D)</p> Signup and view all the answers

<p>Cl––HCO3– exchanger (A)</p> Signup and view all the answers

<p>They are absorbed easily in great quantities (B)</p> Signup and view all the answers

<p>Calcium (D)</p> Signup and view all the answers

<p>Secondary active transport with sodium ions (D)</p> Signup and view all the answers

The process by which H2O in parietal cells dissociates into H+ and OH-, with H+ transported to the stomach lumen.

A protective barrier formed by mucus and bicarbonate in the stomach, maintaining a less acidic environment for the epithelial cells.

The acidity level of the stomach, which is approximately 2.0 due to the presence of HCl.

The process that moves H+ ions from parietal cells to the stomach lumen against the concentration gradient, making the stomach more acidic.

A condition characterized by low potassium levels, which can be induced by the process of making the stomach more acidic.

The process of breaking down food into usable substances by mechanical and enzymatic action in the alimentary canal.

Movement of digested food molecules through the small intestine walls into the bloodstream for circulation.

Humans lack enzymes to digest cellulose, making it indigestible food.

Complex carbohydrates that need to be broken down into simpler forms like monosaccharides during digestion.

An enzyme in saliva that begins breaking down polysaccharides into dextrins in the mouth.

The simplest form of carbohydrates, which are the end products of polysaccharide breakdown.

Starch, which is found in foods like grains and potatoes, and is used for energy storage.

Short chains of glucose produced during polysaccharide breakdown by enzymes like salivary amylase.

Phase of digestion where HCl is predominantly produced after the food bolus enters the stomach.

Mainly produced in the gastric phase, primarily by parietal cells.

Cells in the stomach lining that secrete hydrochloric acid (HCl).

Cells that secrete pepsinogen, an inactive enzyme for protein digestion.

Hormone produced by G cells that stimulates HCl production in the stomach.

Reflex that inhibits gastric acid secretion as chyme enters the small intestine.

Hormone released by the small intestine that inhibits gastric acid secretion.

Hormone that inhibits gastric secretions and enhances insulin secretion.

Hormone that inhibits gastric acid production.

Hormone that inhibits growth hormone and gastric secretions.

Enzymes secreted by the pancreas for digestion of proteins, fats, and carbohydrates.

Enzyme that hydrolyzes carbohydrates into disaccharides and trisaccharides.

Enzyme that breaks down fats into fatty acids and monoglycerides.

Enzymes that are activated from their inactive forms (e.g., trypsin activating others).

Enzyme in the small intestine that breaks down disaccharides.

Enzymes at the brush border that convert disaccharides into monosaccharides.

A disaccharide made of two glucose molecules.

A disaccharide composed of fructose and glucose.

A disaccharide made of galactose and glucose.

The microvilli of enterocytes where nutrient absorption occurs.

Locations where carbohydrate digestion occurs: buccal cavity, stomach, small intestine.

Cells lining the small intestine, involved in nutrient absorption.

Compounds that help emulsify fats for digestion in the small intestine.

Tiny lipid structures formed by bile salts that help absorb fats.

The presence of excess fat in stool.

Types of fatty acids absorbed directly into the bloodstream from enterocytes.

Fatty acids that form inside enterocytes and require more processing.

The reduction of lipase activity, affecting fat digestion.

A drug that inhibits lipase to reduce fat absorption, leading to weight loss.

Chloride ions are absorbed in the small intestine mainly by diffusion, following sodium ions' electrical gradient.

Chloride absorption depends on the levels of parathyroid hormone and Vitamin D in the body.

In the ileum and large intestine, chloride is absorbed via the Cl–HCO3– exchanger in the brush border membrane.

Chloride diffuses into the blood through channels in the basolateral membrane after being absorbed in cells.

Bacteria in the large intestine produce acid from undigested particles, requiring bicarbonate to neutralize it.

When chloride exits, bicarbonate is brought in to maintain electrical neutrality in the intestines.

Calcium is actively absorbed in the blood, with absorption influenced by parathyroid hormone and Vitamin D.

Iron is actively absorbed in the small intestine, depending on hemoglobin production needs.

Potassium and magnesium are actively absorbed through the intestinal mucosa during digestion.

Monovalent ions are absorbed in large quantities, while bivalent ions are needed in smaller amounts.