Nutrition Chapter 4

How much bile does the liver make every day?

2-4 cups

What is the pH level of chyme?

2.0; which is more acidic than lemon juice or vinegar.

On average, about how many hours does the stomach empty?

4 (depends on the food)

Intrinsic factor

Substance necessary for absorbing vitamin B-12

Lower esophageal sphincter

a muscular ring that controls the flow between the esophagus and stomach

enterocytes

absorptive cells that form the outer layer of a villus

dysbiosis

an imbalance in beneficial and detrimental gut microbial populations that promotes disease states

gastroesophageal reflux (GER)

burning sensation generally felt in the back of the throat and upper chest that results from the passage of acidic contents from the stomach into the esophagus

gastroesophageal reflux disease (GERD)

chronic condition characterized by frequent heartburn that can damage the esophagus

fecal microbiota transplantation (FMT)

introduction of fecal material from one person into another person's large intestine

probiotics

live microbes that promote good health for their human hosts; products that contain beneficial microbes

gut microbiota

populations of microorganisms that reside in the large intestine

Pyloric sphincter

ring of muscle that guards the opening between the stomach and the duodenum

Jejunum

second part of the small intestine

Mucus

slimy fluid secreted by the mucous membranes

external anal sphincter

sphincter that allows feces to be expelled from the anus and is under voluntary control

prebiotics

substances in foods that promote the growth of beneficial microbes

Ileum

the last and longest portion of the small intestine

Villi

tiny, fingerlike projections of the small intestinal mucosa that are involved in digestion and nutrient absorption

What are the functions of intestinal bacteria?

Controls inflammation, and synthesizes vitamins in certain neurotransmitters

Pyloric Sphincter

Controls passage of food from stomach to small intestine.

What are the three components of gastric juice?

Digestive enzymes, mucus and hydrochloric acid, and intrinsic factor.

What is the function of the pancreas?

Secretes bio carbonate ions to neutralize HCI.

Lumen

Space within a tubular part or organ, such as the space within an intestine.

Hormone

A chemical messengers that conveys information to target cells.

The gut microbiota is an ecosystem of what 3 things that colonize the intestinal tract.

Bacteria, Viruses, and Fungi

What are the primary rules of the digestive system? (3)

Break down food into smaller components called nutrients, absorb nutrients, and illuminate solid waste products.

Mastication

Chewing food

ileocecal sphincter

Circular muscle at the end of the ileum that controls the rate of emptying undigested material into the large intestine.

What are the pH levels of alkaline solutions?

Higher than 7

The hepatic portal vein takes water soluble nutrients to the what?

Liver

Fermented foods change what?

There chemical composition of the food.

Saliva

Watery fluid that contains mucus and a few enzymes; used to soften food for swallowing.

Hypogeusia

A condition characterized by the DIMINSHED ability to taste

Diverticulosis

A condition characterized by the presence of tiny pouches the form in the wall of the colon.

Dumping Syndrome

A disorder that occurs when a large amount of chyme flows too rapidly from the stomach into the small intestine.

Epiglottis

A flap of tissue that seals off the windpipe and prevents food from entering.

Bile

A greenish yellow fluid that is needed for fat digestion and absorption.

Gastrin

A hormone

What are the four parts (after the Cecum) of the colon (large intestine) and what order are they in?

Ascending colon, transverse colon, descending colon, sigmoid colon.

What are the typical symptoms of Gastric Ulcers?

Deep, dull upper abdominal pain and a feeling of fullness that occur about 2 hours after eating.

Each villus has an outer layer of absorptive cells called what?

Enterocytes

Rugae

Folds in the mucosa lining the stomach.

What are the pH levels of acidic solutions?

Lower than 7

What are the four types of gastric gland cells and what do they secrete?

Mucous (mucus), parietal (components that form hydrogen and chloride ions), chief (pepsinogen and gastric lipase), and g cells (gastrin).

What is the primary secretion of the large intestine?

Mucus

Esophagus

Muscular tube that extends about 10 inches from the pharynx to upper portion of the stomach.

What are some causes of taste and smell disorders?

Obstruction of the nasal passage ways, brain tumors, dental disease, irritation of the inner lining of the nose due to common colds or allergies, ear infections, respiratory infections, radiation treatment, antibiotics for Anna histamines, heading injury, or poor dental health.

Identify the five ways that nutrients can be absorbed by enterocytes.

Simple diffusion, facilitated diffusion, active transport, osmosis, and endocytosis.

What parts of the body produce most of the digestive enzymes?

Small intestine and salivary glands

Dumping syndrome often occurs following what type of surgeries? (3)

Stomach, bariatric, esophageal.

Bioavailability

The amount of a particular nutrient that can be effectively digested, absorbed, and used by the body.

Chemical Digestion

The breakdown of large nutrient molecules in food into smaller components, primarily by the action of stomach acid in various enzymes.

Cecum

The cavity in which the large intestine begins and into which the ileum opens.

Ageusia

The complete LOSS of sense of taste.

Anosmia

The complete inability to detect odors.

Mucosa

The innermost layer of the human digestive tract; in some parts of the digestive system, it contains mucus-secreting cells and glands that secrete digestive enzymes.

What are the primary components of G.I. tract? (7)

The mouth, esophagus, stomach, small intestine, large intestine (colon), rectum, and anus.

What type of nutrients are absorbed into the hepatic portal vein and eventually to the liver before they enter the general circulation?

Water soluble compounds

Salivary Amylase

Initiates chemical digestion in the mouth by beginning the breakdown of starch.

Peristalsis

Involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system.

What is the function of the liver?

Manufacturing bile and cholesterol.

Gastrointestinal Tract (GI)

Part of the body in which digestion occurs and is a hollow, muscular tube that extends approximately 16 feet in length.

Chyme

Partially digested, semiliquid food mixed with digestive enzymes and acids in the stomach.

Pharynx (throat)

Performs the swallowing action that passes food from the mouth into the esophagus.

Absorption

Process of Nutrient uptake from the G.I. tract for transport through the circulatory or lymphatic systems.

Digestion

Process of breaking down large food molecules into nutrients that the body can use.

What foods have a potent umami taste?

Protein rich foods, cooked pork, beef, and fish, as well as certain cheeses, tomatoes and mushrooms.

Salivary Glands

Structures that produce saliva and secrete the fluid into the oral cavity.

List the taste sensations that human taste buds detect.

Sweetness, bitterness, sourness, saltiness, umami, and oleogustation.

Mechanical Digestion

The physical breakdown of food as it passes through the G.I. tract.

What are the main functions of the stomach?

The secretion of chemical messengers that regulate digestion, production and secretion of HCI, in the beginning of chemical digestion of protein

What are some functions of intestinal bacteria?

Warding off pathogens, breaking down toxic substances, and helping with the development of the immune system.

Gastric juice

Watery solution of stomach secretions that include mucus, hydrochloric acid, intrinsic factor, and digestive enzymes.

Anus

A muscular opening at the end of the rectum through which waste material is eliminated from the body.

Lysozyme

An enzyme in saliva that can destroy some bacteria that are in food or the mouth.

Lingual Lipase

An enzyme that breaks down fat; the lipase is typically inactive until it reaches the stomach.

Zymogen

An inactive form of an enzyme that is stored in cells until it is needed for digestion.

Ulcerative colitis

An inflammatory process that causes ulcers to form in the mucosa of the colon and rectum.

GABA

An inhibitory neurotransmitter in the brain.

In contrast of the small intestine, the large intestine what?

Has increased bacterial action and lacks villi

Secretin

Hormone secreted by the duodenum and first part of the jejunum that stimulates the pancreas and liver to release a bicarbonate-rich solution into the small intestine.

What do organs produce the most I just have enzymes?

The small intestine and pancreas

What are the accessory components of the G.I. tract? (6)

The teeth, tongue, salivary glands, liver, gallbladder, and pancreas.

When does heartburn or acid reflux occur?

When the lower esophageal sphincter fails to close properly.

Oleogustation

Ability to taste fat.

Enzyme

A proteins allows chemical reactions, such as the breakdown of large carbohydrate molecules into smaller components, to occur at a rapid rate.

Rectum

A short tube at the end of the large intestine where waste material is compressed into a solid form and stored before being eliminated.

What are some symptoms or signs of dumping syndrome?

Abdominal fullness, nausea, sweating, rapid heart rate, and weakness not long after eating a meal, and can be followed with abdominal cramps and diarrhea.

What are the signs and symptoms of IBD?

Diarrhea, rectal bleeding, abdominal cramps, fever, and unintentional weight loss. In some cases, skin rashes or sores, blurry vision, and joint pain also develop.

Duodenum

First part of small intestine; most digestion takes place here and chemicals are released from the liver, gall bladder, and pancreas to aid in digestion.

Cholecystokinin (CCK)

Hormone secreted by the mucosa of the small intestine that stimulates the gallbladder to contract and the pancreas to release pancreatic juice into the small intestine.

How and/or why do ulcers occur in the stomach?

The thick layer of mucus which protects the stomach lining breaks down and stomach acid makes contact with the stomach wall destroying the tissue.

Trachea

The windpipe; a passage through which air moves in the respiratory system.

Sphincters

Thickened regions of circular muscle that function like valves to control the flow of contents at various points in the G.I. tract.

What is the role of beneficial bacteria in the large intestine?

To make some vitamins and neurotransmitters, and to metabolize undigested food

internal anal sphincter

circular muscle that allows feces to be moved from the sigmoid colon into the rectum and is under involuntary control