Food Nutrition Quiz 2

Digestive System

body systems consisting of the GI tract and accessory structures

(liver, pancreas, and gallbladder)

What is the main function of the digestive system

break down food, absorb nutrients, and eliminate waste

What is the main function of the GI tract

digestion and absorption of nutrients

Types of digestion

Mechanical: physical breakdown of food for digestion/absorption of nutrients

Chemical: breakdown of large nutrient molecules in food into short components

GI Tract

Mouth, esophagus, stomach, small intestine, large intestine, and the rectum

Mouth (oral cavity)

preforms chemical and physical digestion

(amylase: produced in saliva and breaks down carbs)

saliva contains: amylase (starch digestion), lipase (fat digestion), and mucus (lubricant)

taste receptors: unami (broth, meaty, and savory flavors) and oleogustus (taste for fat)

Esophagus

primary function: transfer the bolus (mass of moistened swallowed food) into the stomach - regulates the movement of food

esophagus sphincters: upper (opens to let food from the throat to the esophagus) and lower (closes the opening of the esophagus to the stomach)

muscular tube-10 in. long

connects the throat (pharynx) to the stomach

(no digestion/absorption)

Stomach

Primary function: temporarily stores, mixes, and dissolves ingested food

chyme: mixture of stomach secretions and partially digested food

pyloric sphincters: controls the rate of chyme release into the small intestine

gastric secretions- gastric juice: water hydrochloric acid enzymes

HCI (hydrochloric acid): activates digestive enzymes and partially digests food protein

Small Intestine

Primary function: primary site for nutrient digestion and absorption

Consists of 3 sections: duodenum (main site for chemical digestion), jejunum (main site for absorption of nutrients), and Ileum (absorbs the remaining nutrients)

Villi: fingerlike protrusions that help digestion and absorption

absorption cells: intestinal cells that line villi and participate in nutrient absorption

microvilli: helps digest proteins and carbs

Nutrient Absorption Process

Passive Diffusion: nutrients move from the cell membrane higher to lower concentration — no energy/carrier

Facilitated Diffusion: uses carrier protein to move nutrients from higher to lower concentration — no energy but requires protein

Active Absorption: moves nutrients from lower to higher concentration — requires both energy and carrier

Large Intestine

made up of five segments:

cecum: absorbs water, electrolytes, and salt

ascending colon: absorbs remaining cecum nutrients

transverse colon: good bacteria breaks down fiber

descending colon: stores and solidifies waste

sigmoid colon: holding chamber for solid waste

The Rectum

Last portion of the large intestine

Anal sphincters: help control expulsion

Accessory Organs

Liver: processes and stores nutrients, synthesizes cholesterol, and makes bile

Galbladder: stores bile

Pancreas: produces and secretes digestive enzymes to neutralize the highly acidic chyme

Probiotics

live microorganisms from food or supplements that can have beneficial effects on the body (adequate amount)

found in fermented foods and supplements (has to be live/active)

killed in heat

Prebiotics

selectively fermented ingredients that result in specific changes in composition and activity of gas

Postbiotics

metabolic by products of microorganisms that colonize the human body

Parabiotic

inactivated cells or cell extracts of probiotic microorganisms that may confer

Symbiotic

combination of pro/pre biotics taken to confer health benefits on host

Gut Microbiome

promotes a healthy gut in which probiotics, prebiotics, and postbiotics reduce inflammation toxins and improve the immune system

indigestible protein, sugar, and antacids + antibiotics can increase chances for diseases

Irritable Bowel Syndrome (IBS)

hard time digesting certain carbs

symptoms: abdominal pain, gass, bloating

treatments: elimination diet, limit caffeine intake, low fodmaps

FODMAP Diet

limit short chain carbs

Fructose: fruit sugar

Lactose: sugar in milk

Fructose: wheat garlic

Galactans: beans, lentils

Polyols: avocado, cherries

Inflammatory Bowel Disease

Crohn’s Disease: mostly in the ileum but also all layers of the intestine

Ulcerative Colitis: ulcers or cores in the colon/rectum

Celiac Disease: chronic, immune-meditated disease precipitated by exposure to dietary gluten in genetically predisposed people

—Symptoms: cramps, fatigue, weight loss, anemia, infertility, and bone loss

Non-Gluten Celiac Disease

no as much damage in the small intestine but still the same symptoms

Carbohydrates

main fuel source for the brain, nervous system and red blood cells

(single/complex)

4 kcal/gram

Glycogen: storage form of glucose in the body— regulates blood glucose

Simple: one sugar- monosaccharide (1) + disaccharide (2)