Carbohydrates and the Digestive System

Gallbladder

Organ that stores bile and releases it into the small intestine

Enzymes

Protein molecules that speed up chemical reactions

gastrin

stimulates secretion of HCl

ghrelin

stimulates appetite and increases gastric emptying

secretin

inhibits gastric secretion and motility and increases output of water and bicarbonate from the pancreas

gastric inhibitory peptide

inhibits gastric secretion and motility

Cholocystokinin (CCK)

stimulates contraction of gallbladder to expel bile

Mouth

Entry point for food into the digestive tract

Cephalic Phase

Phase of digestion triggered by the sense of smell and sight

Saliva

Contains salivary amylase and lysozymes to break down carbs and inhibit bacterial growth

Organs

Part of an organ system

Pancreas

Part of both the endocrine and digestive systems

Digestion

Process of breaking food into smaller pieces for absorption

Absorption

Process of taking substances into the interior of the body

GI tract

Hollow tube from mouth to anus involved in digestion and absorption

Pharynx

Part of the GI tract that swallows chewed food mixed with saliva

Esophagus

Part of the GI tract that moves food from the mouth to the stomach

Stomach

Part of the GI tract that churns food, secretes acid, and digests proteins

Small Intestine

Part of the GI tract that completes digestion and absorbs nutrients

large intestine

Part of the GI tract that absorbs water and some vitamins and minerals, and passes waste

Anus

Opening that allows waste to leave the body

Accessory Organs

Organs that aid in digestion but are not part of the GI tract

Salivary Glands

Glands that produce saliva to digest starch

Liver

Organ that produces bile and digests and absorbs fat

Pancreas

Organ that releases bicarbonate to neutralize intestinal contents

Mucus

Viscous material that moistens, lubricates, and protects the GI tract

Digestive Hormones

Hormones that regulate gastric secretion and motility

Chewing

Process that breaks down food and increases surface area for digestion

Esophagus

Muscular tube that moves food from the mouth to the stomach, pushing bolus down, peristaltic contraction reaches stomach and causes sphincter to relax so bolus enters tummy

Stomach

Organ with 3 muscle layers, longitude, circular, diagonal that churns food and secretes acid

stomach lining

mucosa, connective tissue, 3 smooth muscle layers, connective tissue

gastrin

increases before food enters stomach

Small Intestine

Organ where digestion is completed and nutrients are absorbed, absorption is easy to get to here, microvilli is on the mucosoal cell here

Pancreas

Organ that secretes digestive enzymes and bicarbonate ions into the small intestine

Sugars

Carbohydrates that break down into fiber, sugars, and short glucose chains

Proteins

Macromolecules that break down into polypeptides and amino acids

Lipids

Macromolecules that require separate digestion

Nutrient Absorption

Process of absorbing nutrients through simple diffusion, facilitated diffusion, or active transport

facilitated diffusion

fructose

active transport

amino acids

simple diffusion

fatty acids

Large Intestine

Organ that absorbs water and some vitamins and minerals

Intestinal Microbiota

Bacteria produced in the large intestine, healthy means you have good level of inflammation, immune function, and epithelial barrier

Dietary Fiber

Undigested food components that promote bowel health

Prebiotics

Fibers that serve as a food supply for beneficial bacteria

Probiotics

Consumption of healthy beneficial bacteria

Immune Function

GI tract's role in protecting the body from infection, limits absorption of toxins and disease causing organisms, some cells of __ are present in GI tract

Digestive Problems

Conditions such as heartburn (acid in esophagus) and peptic ulcers(open sores in the lining of esophagus, stomach, or upper portion of SI caused by acid resistant bacteria)

Cardiovascular System

System that transports nutrients throughout the body, blood can be measured easily so blood glucose and blood lipids can be measured

Liver

Organ where most nutrients go after absorption

Lymphatic System

System involved in fluid balance, immune function, and absorption of lipids

Mitochondrion

Organelle involved in energy metabolism

Metabolism

Series of reactions that transform food into energy

Catabolic Reactions

Reactions that release energy trapped in chemical bonds, catabolic to ATP

Anabolic Reactions

Reactions that use energy to form more complex substances

ATP

Energy currency of the body, 3 phosphate groups and adenosine

glucose

Most important carbohydrate for the body

pyruvate

breaking down glucose makes,

pyruvate

makes acetyl coA to put into the citric acid cycle

citric acid cycle

makes co2 and high energy electrons that create water

kidney

filters out water and small molecules to be lost in feces

nitrogen

waste leaves in urine

large intestine

produces biotin and vitamin K

fermentation

breakdown of carbs and protein anaerobically

probiotic

food containing live bacterial cultures, enhance immunity, prevent colonization by pathogens, lower pH of colon, transform/promote excretion of toxins and enhance fecal bulk

Prebiotics

food ingredients that promote bacterial growth

carbohydrate

intake has increased in the US, but fiber did not, more than 1/2 cals from americans bc readily available

whole grains

unrefined/ have stabalized grains and make sure lipids aren't oxidized

unrefined carb

have a variety of nutrients in addition to carbs

refined carbs

lost all of their healthful components, separates carbs from essential nutrients, must have it written on them, might be enriched with things, dont have vit e/ b6

bran

fiber and vitamins

germ

source of veggie oils, corn oil, and vitamin E oil, protein, fiber

endosperm

starch, protein, vitamin, mineral

enriched grain

have added nutrients but not vit e magnesium or vit b6

monosaccharide

basic carb, not in food supply, we make them in our bodies

glucose

blood sugar, most important carb, found as disaccharide or starch

blood sugar, important carb for the body

galactose

milk monosaccharide

sucrose

only sweetener in the US that can be labeled as sugar, glucose and fructose,, the standard

fructose

fruit and veg monosaccharide

Oligosaccharides

found in GI tract, beans, not digested by enzymes and passed to colon, complex carb, 3-10 mono,

Glycogen

Storage form of carbohydrates in animals, can only store small amount that increases with carb loading

Starch

Storage carbohydrate in plants

Fiber

Carbohydrates that are not digested by human enzymes,

soluble___ is broken down in water

Lactose Intolerance

Inability to digest the milk sugar lactose

symptoms occur when there isn't enough lactase in the SI to digest lactose, becomes more prevalent with age, 65% of human population has the reduced ability

fiber

not digested and not readily absorbed, human enzymes don't break down their subunits, increases volume of material in lumen of intestine, binds minerals preventing absorption,

presence affects GI, intestinal microbiota, amount of intestinal gas, weight of material in lumen

glucose to body

concentration of glucose is regulated by liver and enzymes secreted from pancreas

Glycemic Response

How quickly blood glucose rises after consuming carbohydrates

Glycemic Index

Ranking of how a food affects the glycemic response

Glycemic Load

Calculation of a food's glycemic index multiplied by the amount of available carbohydrate in a serving of food

Blood Glucose Regulation

Control of blood glucose levels by insulin and glucagon

immediately after a meal, BG level increases, insulin is released, stimulating the storage of glucose, then BG drops and glucagon is released

Cellular Respiration

Process by which glucose is metabolized to produce ATP

aka aerobic metabolism

Gluconeogenesis

formation of glucose from noncarbohydrate sources fatty acids to acetyl coA

ketogenesis

creation of ketone bodies when carbs are limited, acetyl coA is used to make ketones

Diabetes Mellitus

Condition characterized by high blood glucose levels

type 1

insulin is no longer made in body

type 2

insulin is present but the cells don't respond

Hypoglycemia

Condition characterized by low blood glucose levels

reactive hypoglycemia

over secretion of insulin in response to carb intake, treatment includes frequent meals with protein

fasting hypoglycemia

abnormal insulin secretion not related to food intake

Carbohydrates and Dental Caries

Relationship between sugar consumption and tooth decay