Chapter 3; Digestion Flashcards
if our digestive system isn’t functioning properly, we are not able to […] our bodies effectively with the nutrients they require
nourish
digestion extracts […], […], and other nutrients from the foods we consume to provide the body with the nutrients it needs for growth, maintenance, reproduction, repair, and continuous renewal of cells, tissues, and organs
vitamins
minerals
the health and proper function of an individuals […] […], then, is just as important as a nourishing diet
digestive system
first/four basic stages to the digestive process; food is ingested through the mouth and enters the […] channel called the […] canal, also called the […] tract (GI tract). the GI tract extends from the […] to the […] and includes the mouth, esophagus, stomach, small intestine, and large intestine
tubular
alimentary
gastrointestinal
mouth
anus
second/four basic stages to the digestive process; as food passes through the GI tract, it is […], or […] down into smaller units
digest
broken
third/four basic stages to the digestive process; the smaller units of nutrients then undergo […], meaning that they pass into the […] or […] system, which transports them throughout the body.
absorption
bloodstream
lymphatic
four/four basic stages to the digestive process; anything not absorbed is excreted as […] through the opening (the anus) at the other end
waste
the inside space of the GI tract is called the […], which is lined with a layer of mucosal cells called the mucosa, so named because it is protected by a layer of thick fluid called [..]. mucosal cells allow our body to […] nutrients so that they can be transported by the blood or lymph to where they are needed
lumen
mucus
absorb
the impaired digestion and malabsorption caused by celiac disease can predispose individuals to an early […]
deatht
Murray found that those with the antibodies against gluten died over subsequent decades than those men whose blood didn’t contain the antibodies
yes
the entire GI tract extends approximately […]-[…] meters (26-30 feet)
8-9
the digestive system includes the organs of the GI tract and […] organs: the salivary glands, liver, gallbladder, and pancreas, and all of which secrete […] contain a variety of agents, such as enzymes and acids, that aid in digestion
accessory
fluids
digestion is composed of two processes: […] digestion and […] digestion
mechanical
chemical
the mechanical and chemical digestion’s break down the nutrients in food into […] and […] components so that the nutrients can be absorbed and utilized by our bodies
smaller
smaller
mechanical digestion is the […] fragmentation of foods into small particles, whereas chemical digestion breaks […] bonds to clear large molecules into smaller ones
physical
chemical
mechanical digestion begins in the […], where teeth crush and tear food into small bits. it continues in the […], as forceful contractions vigorously churn food. this churning action […] the small food fragments and […] large molecules to the digestive fluids that will chemically dismantle them. in many cases, the mechanical digestion is all that is required to release many vitamins, minerals, and phytochemical from foods that are then take up by […] cells lining the small intestine
mouth
stomach
disperses
exposes
mucosal
motility is a term used to describe the […] of the GI tract’s smooth muscles that mix food with digestive […] and propel food along the length of the tract
contractions
fluids
two fundamental patterns of muscle contractions: […] and […]
peristalsis
segmentation
peristalsis creates propulsive muscle contractions to […] food […] through the complete length of the GI tract, from the esophagus to the anus
move
forward
segmentation occurs when […] muscles in the small intestine contract in an […] fashion so that fluid contents gently […] back and forth between the segments
circular
uncoordinated
slosh
contractions serve to […] intestinal contents with digestive fluids and bring nutrients in the intestinal fluid to […] with the small intestines absorptive surface. similar segmentation contractions also occur in the [small or large] intestine
mix
contact
large
chemical digestion is the form of digestion that involves [..] and other substances released from […] glands, as well as from the stomach, small intestine, and pancreas. it takes place in the mouth, small intestine, and stomach
enzyme
salivary
without the work of enzymes, digestion (and many other body processes) could not occur
yes
an enzyme is a […] molecule that functions to catalyze, or sped up, the rate at which a chemical reaction produces new compounds with altered […] structures. these actions may subtly alter the chemical structure, or they may produce dramatically […] or […] molecules
protein
chemical
larger or smaller
in addition to enzymes, other chemicals, such as […], are produced by the various organs of the […] system. hormones are your body’s […] messengers. together with the nervous system, hormones regulate […], […], and the […] of secretions in to the GI tract
hormones
digestive
chemical
motility, appetite, and release
mouth watering anticipation of the first bite, can initiate the mechanical and chemical process of digestion. then biting through food begins the mechanical digestion, increases the surface area available for the enzymes to being their work of chemical digestion. while we chew, the salivary glands near the jaw and under the tongue release saliva, which lubricates the mouth and esophagus and contains salivary amylase, an enzyme that starts digesting the carbohydrates in the bun, as well as lipase, which beings digesting fats in the meat. the tongue mixes saliva with the foods in the mouth and pushes the food to the back of the mouth to initiate the swallowing
the tongue contains taste buds that help us identify or sense foods on the basis of specific flavors or tastes. (sweet, sour, salty, bitter, and umami). the number of taste buds declines with age. taste buds also create signals that tell the rest of the GI tract to prepare for the next steps of digestion. once coated with saliva the food comes soft, and a moist lump of food known as bolus , which is swallowed and passed through the throat. enters esophagus. positioned at the junction of the esophagus and the stomach is a circular muscle (sphincter) that normally functions as a one way valve.As food nears the lower-esophageal sphincter, that sphincter relaxes to let food pass into the stomach; otherwise, the sphincter stays tightly closed to prevent foods and secretions in the stomach from moving backward into the esophagus.
bolus then enters the stomach, a muscular, I -shaped sack that can accommodate up to 4 cups of food and generally takes about 2 to 4 hours to empty. the stomach secretes gastric juices that contain hydrochloric acid (HCL) which help to unfold the proteins in the food through chemical digestion. the gastric juices also contain enzymes such as proteases that digest proteins and lipase that digests fat. they also contain mucus that lubricated the food and protects the stomach lining from acidity. forceful peristaltic contractions of the stomach vigoursly churn, fragmenting the food into fine particles that are dispersed throughout the gastric fluid. essentially grinding the food into a semiliquid mass called chyme. few teaspoons at a time chyme is passed along to the small intestine, moving through the partially relaxed pyloric sphincter that functions as a sieve, allowing only small food particles to pass through
the stomach empties into the small intestine depends on the composition and quantity of the foods and fluids you consume. food with more fiber, slows emptying from the stomach, helping you feel full, or satiated. but as it passed into the large intestine, it can also stimulate propulsive contractions, which speed up the transit of the intestinal content through the rest of the digestive system, which help promote regular bowel movements,
the small intestine is the primary site for the […] of food and the […] of nutrients, it is where digestion can go awry in people with celiac disease
digestion
absorption
the small intestine has three sections; the […], the first portion of the small intestine after the […]; the […], the middle portion; and the […] the last and longest portion
duodenum
jejunum
ileum
the internal circular folds of the small intestine carry fingerlike projections called […] that increase its surface area for […]. villi are densely covered with fine hairlike projections called microvilli that further increase the surface area and the efficiency of absorption , lining is often called the […] border
villi
absorption
brush
chyme that enters the small intestine form the stomach is very […], and if it doesn’t get neutralized, it denatures and [..] the enzymes required for digestion. the pancreas releases pancreatic juice that contain bicarbonate akin to baking soda that […] the gastric acids to chyme
acidic
inactivates
neutralized
the […] and the […] also help to digest lipids
liver
galbladder
the liver produces [..] - which is stored in the […], a small, pear shaped sac below the liver in the right upper abdomen- that contains substances critical for effective […] digestion
bile
gallbladder
lipid
the hormone cholecystokinin (CCK) is released from the small intestine in response to the hamburgers fats and protein in the small intestine; CCK stimulates the gallbladder to release bile and the pancreas to secrete juice into the lumen of the small intestine. pancreatic juice contains enzymes that further break down molecules into smaller ones. enzymes located in the brush border complete the digestion
To enter the mucosal cells lining the GI tract, water and small amounts of a few other nutrients can pass directly through the cell membrane by simple diffusion. The cell membrane serves as the boundary that holds the content of the body’s cells in place and keeps their internal structures safe so that cells function properly. the membrane also serves as a semipermeable filer through which nutrients can enter and wastes can be excreted. many nutrients enter the cells by facilitated diffusion, which requires a specific transport protein to help each of these nutrients move through the cell membrane
to move nutrients from the food in our intestines into our cells, our bodies use both […] and […] transport methods. […] transport includes both simple and facilitated diffusion. simple diffusion occurs when some nutrients such as water and lipids are able to move freely from the digestive tract into the intestinal cell
passive and active
passive
other nutrients are not able to freely cross the cell membrane but are still transported down a concentration gradient
yes
the embedded protein is able to facilitate or carry the the molecules through the cell membrane into the cell by a process called […] […]
facilitated diffusion
since both simple diffusion and facilitated diffusion carry nutrients from an area of high concentration– the lumen – to an area of low concentration inside the cell, no [..] is required to absorb these nutrients
energy
when molecules need to move […] a concentration gradient, active transport is required. nutrients such as glucose are found both in the intestinal lumen after eating and inside the cell as a source of energy
against
the circulatory system, which includes both […] […] and the […] system, distributes vital nutrients to […] and […]
blood vessels and the lymphatic system
tissues
organs
e.g. carbs, amino acids, minerals, and water-soluble vitamins enter directly into blood vessels where they are transported in blood to the liver before reaching other organs. most fats, (and some vitamins) enter lymph (a watery fluid surrounding tissue) and travel through the lymphatic system before they fid their way into the blood. as a result, they reach the liver only after circulating throughout the rest of the body.
some nutrients as well as many toxins we ingest are largely removed from the blood by the […], where they are then metabolized
liver
metabolism includes all of the […] reactions that occur within the human body that convert one molecule into another molecule to provide [..] or to synthesize substances that are required to sustain [..]
chemical
energy
life
from the small intestine, any undigested nutrients that remain in the chyme are passed into the […] intestine, which consists of the cecum, colon, and rectum. here little […] or […]take place; there are no villi. secreted mucus protects and lubricates in the smoother lining of the large intestine, making it easier for everything thats left over to be excreted as […]
large
digest or absorption
feces
but before the food is excreted the large intestine will extract […] (sodium, chloride, and potassium), some […] acids, …, and […]
electrolytes
fatty
vitamins
water
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the large intestine contains hundreds of different types of […] that feed on undigested fiber and starch; because humans have no […] that digest dietary fiber, these bacteria perform some of that function, producing gas and short chain fatty acids in the process
bacteria
enzymes
some bacteria play a role in preventing disease, reducing the […] of other bacteria that may cause it. when microbes, including bacteria, cause disease, they are known as […]
activity
pathogens
the bacteria that inhabit our GI tract are the dominant component of our gut […] - the complex community of all micro organisms (such as […] and even […]) that live there
microbiota
bacteria
fungi
a healthy gut microbiota contains a […] and well […] array of hundreds of different types of […] that have an intricate and interactive relationship with each other and their human host
diverse
balanced bacteria
there is communication between microbes in our […] and the […]
gut
brain
disruptions to the balance of microbes inhabiting our gut, and/or a decrease in their diversity, is linked to a number of human maladies, including inflammatory bowel diseases, allergies, autoimmune diseases (such as celiac disease), diabetes, cancer, obesity, depression and anxiety, and perhaps even autism
yes
consequently, maintaining an appropriate gut microbial balance is critically important to our overall health. although many factors affect the intestinal microbial population, […] has a potent influence on its composition
health.
diet
e.g. geography, genetics, age, medications, and stress
one of the means by which diet influences the gut microbiota is through the ingestion of live, beneficial […] found in some foods and in dietary supplements. these helpful microbes are known as […] - a word you may have seen on food, beverage, or supplement labels
microbes
probiotics
the world health organization defines probiotics as “[…] microorganisms, which when consumed in adequate amounts confer health benefits on the host”. their temporary residence cause […] shifts in the microbial population to help maintain or restore a healthy […] of “friendly” banter and other microbes
live .
healthy
balance
evidence for probiotic effectiveness appears to be limited to alleviating symptoms of both […] and […]
diarrhea
constipation
probiotics are found naturally in […] foods
fermented
e.g. dairy products (yogurt, buttermilk, and kefir)
+ soy sauce (if unpasteurized, tempeh (soybean cake), miso (soybean paste), and kombucha (tea)
prebiotics are primarily undigested […] that healthy bacteria use to boost their […] in the large intestine
carbohydrates
growth
(side note; you can think of prebiotics as substances that “feed” or nourish good bacteria)
[…] effects on the gut microbiota is relatively small, but […] strongly influence our gut microbe population
probiotic
prebiotics
eating prebiotics may prevent and treat […] and […] cancer, boost the absorption of […], reduce levels of […] in the blood, and help […[ blood glucose.
diarrhea
colon
minerals
fat
control
prebiotics can also reduce the risk of […] infections, because in order to establish infections, “bad” bacteria must adhere to the lining of the gut. as “good” bacteria increase in the gut in response to the ingestion of prebiotics (or in response to probiotics), they take up more and more real estate, making it difficult for the bad bacteria to find a home
gastrointestinal
as the number of good bacteria increases, they grab the majority of the available […], leaving little for the unwanted microbes. sources of prebiotics include chicory, Jerusalem artichokes, whole-grain rye, oats, wheat, and barley, leeks, garlic, and onion
nutrients
in the list of prebiotic rich foods (rye, wheat and barley) since it is gluten it harms people with celiac disease. making them consume fewer prebiotics and therefore have a significantly different mix of bacterial species in their guts
yes
in a study, with infants predisposed to celiac disease, the balance of bacteria and their metabolic products shifted before the infants developed celiac disease, hence scientists may be able to predict when the children will develop autoimmunity. allowing doctors to give probiotics or prebiotics that restore the balance of their gut bacteria and perhaps stave off the disorder
yes
even though celiac disease can damage the small intestine, its effects are also felt throughout the body. the “extra intestinal” effects are likely due to a combination of ongoing […], nutrient […], and possibly an adaptive […] response spreading from the intestinal mucosa to other tissues and organs
inflammation
deficiencies
immune
vomiting - the […] movement of stomach contents from the stomach through the mouth and out of the body- can be caused by many things, including emotional stress, motion sickness, viruses, or food borne bacteria
forceful
acid reflux is the condition caused by occasional […] of food (stomach contents, including acid) back into the esophagus from the stomach and characterized by a […] feeling in the esophagus. (burning feeling is called heartburn)
regurgitation
burning
gastroesophageal reflux disease (GERD) is a recurrent and more […] form of acid reflux that is accompanied by […] and/or […] of the esophageal lining along with […]
serious
inflammation
erosion
pain\those with untreated GERD can be at risk for certain cancers or other complications. fortunately over the counter and prescription drugs can treat GERD
gallstones; small pebble substances that develop in the […]. the gallbladder is a small, pear-shaped sac located below the liver in the right upper abdomen that stores […] fluid. gallstones form when substances in bile […] (crystalize) into pieces of stonelike material
gallbladder
bile
harden
hemorrhoids are swollen and inflamed […] in the […] and lower […]. hemorrhoids can be related to low […] diets and chronic […] or […]
veins
anus
lower rectum
fiber
constipation
diarrhea
gastritis; is […] of the stomach, often causing […] and/or […]. gastritis can be caused by alcohol, certain medication, H. pylori infection, or other factors. in some cases, it can cause atrophy (atrophic gastritis) of stomach cells that produce hydrochloric acid
inflammation
nausea
pain
p.s. gastric acid causes tissue damage
an ulcer is irritation or perforation of […] wall caused primarily by […] (H. pylori), but may also be due to a breakdown of normal […] mechanisms of the GI tract lining (e.g., decrease in mucus production caused by (NSAID). often causes pain, and bleeding can occur in the stomach (gastric) or small intestine (duodenal), conditions termed peptic ulcers
mucosal
infection
protective
bleeding
diverticular disease is a condition in which there are small […] or […] in the wall or lining of any portion of the digestive tract. these pockets occur when the inner layer of the digestive tract pushes through [strong or weak] spots in the [inner or outer] layer. a single pouch is called a diverticulum
pouches or pockets
weak
outer
many digestive disorders include the symptom of […], which is defined as frequent loose and watery bowel movements that occur more than three times a day
diarrhea
constipation, having a bowel movement fewer than […] times per week, is another symptom common in digestive disorders
three
consuming sufficient […] along with adequate […] intake softens stools because it holds water, thus decreasing the risk of both constipation and painful inflamed veins in the lower rectum or anus, a condition called hemorrhoids
fiber
fluid
age is a primary risk factor. a diet rich in fiber along with an active lifestyle appear to have a significant protective effect
irritable bowel syndrome (IBS) is a group symptoms, including abdominal […], […], […], and other discomforts, caused by changes in how the GI works. this disorder affects the muscle […] of the colon (large intestine).
pain
bloating
diarrhea
contraction
IBS does not lead to serious disease such as cancer, and does not permanently harm the large intestine
the foods that may trigger IBS symptoms, must take note of the foods or beverages, such as caffeine, alcohol, fatty foods, and some non -nutritive sweeteners, that may cause difficulty
yes
when diarrhea occurs, water consumption must be increased to avoid dehydration
yes
inflammatory bowel disease (IBD) is a broad term that describes […], […] conditions that are caused by an abnormal response by the body’s immune system, which causes […] of the GI tract
serious
chronic
inflammation
the most common IBDs (inflammatory bowel disease) are […] colitis and […] disease.
ulcerative
Crohn’s
in ulcerative colitis, the mucosa of the intestine becomes [..] and […] and ulcers (open wounds) develop. ulcerative colitis is often most severe in the […] colon (the rectum), which can cause diarrhea.
irritated
swollen
lower
Crohn’s disease most often affects the lower portions of the small intestine and parts of the large intestine. however it can attack any part of the digestive tract
lower
individuals with IBDs are at risk for serious or even life threatening complications. includes bowel [..] (caused by the narrowing of the intestinal wall); ulcers in the [..] track, including the mouth and anus; fistulas (an abnormal connection between the intestine and skin or other organs); [..] because of poor absorption; colon [..] ; and problems in parts of the body outside the GI tract, such as kidney stones or arthritis
obstruction
digestive
malnutrition
cancer
a person with IBD needs a nourishing diet to deal with potential nutrient deficiencies brought about by […] issues, as well as assistance when significant weight loss occurs. people suffering with IBDs are teated with anti-[…] drugs and often require surgical procedures to deal with medical complications
absorption
inflammatory
one other symptoms of celiac disease usually not associated with the condition can be a specific type of skin […]. + higher risk of thyroid disease, may also be at higher risk of experience various neurological problems
rash
side note; when patients with the rash cut gluten out of their diets, the rash disappears
