chapter 4 -- connect (digestive system)
the stomach empties in about ____ hours depending on te contents and size of the meal
1-4
the parietal cells of the stomach secrete
HCl
in the small intestines the chyme moves slowly through the circular folds allowing the chyme to
be completely mixed with digestive juices and come in close contact with the villi
digestive enzymes do what?
catalyze chemical rxns
Gallstones are composed of
cholesterol and bile pigments
Feces in the rectum are a powerful stimulation for _______________
defecation
the order of the parts of the small intestine
duodenum, jejunum, ileum
the protein _______ found in wheat and related grains triggers an autoimmune response in individuals with celiac disease
gluten
what is irritable bowels syndrome effect on cancer?
has no effect on the risk of cancer
the acid-resistant bacteria, ______ is one of the two main causes of peptic ulcers
helicobacter pylori
the two components of saliva
lingual lipase and salivary amylase
the resident bacteria throughout the GI tract are referred to as the gut
microbiota
This GI regulatory hormone is released by the small intestine in response to acidic chyme and stimulates release of pancreatic bicarbonate.
secretin
digestion is
the process of breaking down foods into smaller components
what percent of the U.S. population suffers from irritable bowel syndrome?
10-15%
how long does it take for a meal's residue to travel through the large intestine?
12-24 hours
how much digestive fluid is secreted into the GI tract over the course of a day?
about 29 cups
the function of the epithelial cells are to (4)
absorb nutrients secrete important substances excrete wastes protect underlying tissues
the liver, gallbladder, and pancreas are part of the digestive system but are considered to be _____ structures
accessory
which nutrients are absorbed from the lumen of the small intestine via active absorption?
amino acids and glucose
which nutrients are absorbed from the lumen of the small intestines via active absorption
amino acids and glucose
lifestyle change modifications for GERD and ulcers often include
avoiding foods that cause reflux SX eating small meals instead of large ones not laying down right after eating
HCl destroys what in food?
bacteria and viruses
3 structures made up of connective tissue
cartilage, tendons, bones
order of large intestine
cecum, ascending colon, transverse colon, descending colon, sigmoid colon
This GI regulatory hormone is released by the small intestine in response to fat ands stimulates the release of pancreatic enzymes and bile_
cholecystokinin
the liquid contents of the stomach are a mixture of acid, enzymes, and partially digested food known as
chyme
nutrition therapy for mild cases of constipation includes
consuming more fluids and fiber daily
risk factors for gallstone formation (4)
consumption of high calorie, low-fiber diet excess weight female rapid weight loss or prolonged fasting
common causes of food intolerances include:
deficiencies in digestive enzyme toxic contaminants such as mold or bacteria sensitivities to a food component *(such as gluten)
the gallbladder secretes bile into the duodenum and reabsorbs it in the ileum. this recycling of bile by the liver is part of the ______ circulation
enterohepatic
food intolerances are caused by the inability to digest certain food components, usually due to a lack of specific _____-
enzymes
hydrolysis rxs are catalyazed by
enzymes
swallowing moves food from the mouth to the
esophagus
what are some nutrients that absorbed in the lympathic system?
fat-soluble vitamins and most fats
what is absorbed via passive diffusion?
fats
current research does not support the use of dietary _____ in the treatment of irritable bowel syndrome
fiber
what nutrient is absorbed via facilitated diffusion?
fructose
which nutrient is absorbed via facilitated diffusion?
fructose
experiencing heartburn more than 2 times a week may be a symptom of the digestive disorder ________
gastroespohagel reflux disease
the amino acid that is present in many foods that stimulate the umami taste sensation is
glutamate
How well a persons individual organs work is determined by
his/her overall nutritional state
the main functions of the large intestine (3)
house gut microbiota absorb water and electrolytes form and expel feces
because of the hormones released during pregnancy, a pregnant woman is at _____ risk for constipation
increased
the substance necessary for the body to absorb Vitamin B-12 is...
intrinsic factor
the villi contain ____ to transport nutrients to larger lympth vessels
lacteals
healthy bacteria that reside in the large intestine
lactobacilli and bifidobacteria
beneficial bacteria reside in the ______ intestine
large
the _______ intestine is the main site where electrolytes, espeically sodium and potassium are absorbed
large
pancreatic lipase is responsible for breaking down ________ for digestion
lipids
Fat-soluble nutrients are absorbed into the _____.
lymphatic system
the brush border enzymes of the small intestine are responsible for the chemical digestion of the ______
macronutrients
the digestive organs in the order they come in contact with food
mouth, esophagus, stomach, small intestine, large intestine
which layer of the wall of the instestinal tract has many tiny fingerlike structures that project into the GI lumen and trap nutrients
mucosa
which layer of the wall of the tract as many fingerlike structures that project into the GI lumen and trap nutrients
mucosa
is IBS associated with other serious digestive disorders?
no
is inflammatory bowel disease another name for irritable bowel syndrome?
no
digestive enzymes are very specific with regard to the
pH of the environment in which they function in type of chemical rxn they catalyze vitamin or mineral cofactors they require to function
Waves of muscular contractions that propel food along the GI tract are called
peristalsis
causes of hemorrhoids
pregnancy and obesity straining during BM added stress to the veins of the rectum and anus
main function of the lower esophageal sphincter is to
prevent the backflow of GI tract contents
____________ are living microoragnisms, such as lactobacilli found in yogurt, and when consumed in sufficient amounts, colonize the large intestine and provide health benefits
probitoics
the bacteria found in fermented foods, such as yogurt, kefir, and miso are known as _____ bacteria
probitotic
digestive enzymes are made of
protein
what is needed to facilitate active absorption?
protein carrier and energy
______ weight loss is associated with the formation of gallstones
rapid
what nutrients are absorbed in the cardiovascular system?
short/medium fatty acid chains proteins, carbs, b vitamins, vitmatin c water-soluble nutrients
the most frequent peristalsis takes place in this organ of the GI tract
small intestine
younger people most often develop ulcers in the
small intestine
what is the substance in the pancreatic juice that allows us to buffer the acidic contents arriving in the small intestines from the stomach?
sodium bicarbonate
chyme is formed in the ____ as food is mixed with digestive secretions
stomach
the site of limited nutrient absorption is the
stomach
This layer of the wall of the digestive tract contains blood vessels that carry nutrients and other substances both to and from the GI tract
submucosa
this layer of the four layers of the wall of the intestinal tract contains the blood vessels that carry nutrients and other substances to and from the GI tract
submucosa
phagocytosis occurs when the absorptive cells in the small intestine
surround and engulf a solid compound
the contents of the stomach pass through the pyloric sphincter at a rate of a ____ at a time
teaspoon
the primary function of the pyloric sphincter is to control what?
the flow of food contents from the stomach into the small intestine
the most common forms of inflammatory bowel disease in the U.S. arw
ulcerative colitis and chron's disease
which taste sense is enhanced by the addition of MSG?
umami
what is absorbed in the large intestine?
water and electrolytes
hydrolysis rxns occur when
water mcls are used to break down lg mcls
what nutrients are absorbed in the cardiovascular system
water-soluble nutrients, short/medium fatty acids, proteins/carbs/b and vitamin c
irritable bowel syndrome is more common in younger ______
women
are enzymes specific to one type of chemical process
yes