Digestive System Flashcards
When food is broken down via enzymes and other chemical substances
chemical digestion
When food is physically broken apart
mechanical digestion
When food is moved through the digestive tract
propulsion
When nutrients and water from food are made available to the cells of the body
absorption
Digestion begins in the mouth. Mechanical digestion by ___ increases the __ __ of food and increases its exposure to __ ___. It also makes the food easier to __ and move through the digestive tract. The chewed up food is called the ___. The enzyme ___ in the saliva also breaks down ___ in chemical digestion
chewing, surface area, digestive enzymes, swallow, bolus, amylase, starch
Next food travels from the food to the ___, where food and air passes cross. It contains the ____, which is a flap of tissue that blocks solids and liquids from entering the ____, to prevent airway blockage. It also contains the _ __ ___, which prevents against reflux of ____ from the esophagus, and helps air from entering the digestive tract
pharynx, epiglottis, trachea, upper esophageal sphincter, acid
When food is swallowed, it enters the ____, which is a tube leading to the stomach. Saliva and ____, wave-like contractions keep the bolus travelling down the digestive tract
esophagus, peristalsis
Peristalsis is a series of alternating ___ and ___. It is performed by the __ __, which contracts ___ the food, to move it forward, and relaxes in ____ of the food to let it pass through. This occurs in the ___, ___, ___ ___, and __ __
contractions, relaxations, smooth muscles, behind, front, esophagus, stomach, small intestine, large intestine
Food then enters the stomach through the ____ ___ __/ __ ___, which prevents acid reflux. The stomach secretes ___ ___ (stomach acid) which is a mixture of mostly __ and water, that helps to start the digestive process and destroy harmful ____. The stomach has __ ___ which are indentations in the stomach walls that function as __ ___. The stomach walls also have ___ (folds) that increase the surface area of the stomach which increases the exposure to __ ___, and allow the stomach to ___. They also allow the stomach to ____.
lower esophageal sphincter, cardiac sphincter, gastric juice, HCl, pathogens, gastric pits, exocrine glands, rugae, stomach secretions, expand, churn
____ are rings of muscles that can relax or contract to regulate the ___ of food throughout the digestive system, and prevent the ___ of food through the digestive tract.
sphincters, flow, backflow
The stomach can be used for ____, due to the accordian-like folds that increase the surface area of __ ___. It also aids in mechanical digestion, by contraction of the stomach walls, which mixes the food with __ ___, which produces a slurry like mixture called ___. These contractions also help to physically __ __ down. The stomach also assists in chemical breakdown, as the enzyme ____ digests ____. ___ are also broken down the acidic environment
storage, stomach lumen, gastric juice, chyme, break down, pepsin, proteins, microorganisms
The stomach also contains gastric pits that are used as exocrine glands, as they secrete substances through long ___ into the stomach. These gastric pits are made of ___, ___, ____, ___ and ___ cells
ducts, mucus, chief, parietal, G, ECL
Mucous cells secrete ___ that ___ and protects the stomach’s __ ____ from acid
mucous, lubricates, epithelial lining
The chief cells secrete _____ which is a zymogen, which gets converted to ___ by the low pH in the stomach. It helps to digest proteins into smaller ___.
pepsinogen, pepsin, peptides
Parietal cells secrete ___ which makes the stomach highly acidic, and allows pepsinogen to be ____. into its active form. They also secrete __ ____, which helps aid in the absorption of ___ ____ in the intestines
HCl, cleaved, intrinsic factor, vitamin B12
The G cells secrete _____, which is a ___ hormone that stimulates the stomach parietal cells to release ____
gastrin, peptide, HCl
The ECl cells are stimulated by ____, and will produce _____. This in turn stimulates the parietal cells to produce ___
gastrin, histamine, HCl
___ ___ are wounds in the lining of the stomach that result from excess stomach acid or __ ___, which disrupts the ___ layer of the stomach
peptic ulcers, H. pylori, mucus
The __ leaves the stomach and enters the ___ __ through controlled release by the __ ___
chyme, small intestine, pyloric valve
In the small intestine the majority of __ and __ ___ occurs. There are three segments; the ___, __ and ___
digestion, nutrient absorption, duodenum, jejunum, ileum
The duodenum is where a lot of the digestion takes place. It breaks down __, ___, ___ and __ ___ through __ ___. The duodenum also secretes ____, contains ___ and regulates the ___ of the small intestine
proteins, carbohydrates, fats, nucleic acids, pancreatic juice, secretin, bile, pH
The jejunum is the site of __ ____ and further enzymatic digestion. _____, __ __ and ____ ___ are absorbed through the walls of the jejunum and sent through the ____ for transportation to our cells
nutrient absorption, glucose, amino acids, fatty acids, bloodstream
the ileum is the ___ segment of the small intestine, which continues the absorption of nutrients, capturing anything that was ___ in the previous segment. It also contains __ ___, which area areas of lymphatic tissue that contain __ ___ that check for pathogens in anything passing through the digestive system and mount an __ __ if necessary
longest, missed, peyers patches, immune cells, immune response
The walls of the small intestine are highly ___ and have finger like projections called _____. These increase the __ ____ of the small intestine, which increases digestion and absorption. Within the villi are ___ which are lymph vessels surrounded by a __ ___. These function to absorb and transfer ___. the individual cells that line the villi are called ____ which have a core made of ___ and help to further increase the surface area of the small intestine
folded, villi, surface area, lacteals, capillary network, fats, microvilli, actin
The small intestine also has ___ cells that secretes mucous, which helps to __ and protect the intestinal ____.
goblet, lubricate, lining
The small intestine is ___ acidic than the stomach because ____ ions from the ___ neutralizes the stomach acids
less, bicarbonate, pancreas
The small intestine exhibits ____, as well as ____. The latter is a contracting and relaxing of different ___ of the small intestine, which promotes optimal digestion and the intestinal mixing of chyme, and __ ___.
peristalsis, segmentation, segments, digestive juices
The pancreas acts as an ____ ___, as it secretes major enzymes into the ____. it also secretes _____, which neutralizes the acid in the small intesine
exocrine gland, duodenum, bicarbonate
The pancreas secretes ____ such as ____ and ____, which are zymogens. Trypsin is activated by ______, and goes on to activate ____. Collectively these break down ____
proteases, trypsin, chymotrypsin, enterokinases, chymotrypsin, proteins
The digestive enzymes of the pancreas are secreted as part of the _ ___, which flows from the ___ __ to the duodenum. This also contains __, water and ___.
pancreatic juice, pancreatic duct, bicarbonate, electrolytes
The pancreas also secretes _____, which breaks down carbohydrates, ______ which breaks down fats, and _____ which break down nucleic acids
amylase, lipase, nucleases
The pancreas functions as both and endocrine and exocrine gland. The ____ ___ secrete digestive enzymes into the pancreatic duct over __ ___, serving exocrine function. __ of the __ ___ secrete hormones into the blood vessels, serving endocrine function
acinar cells, short distinces, islets, langerhans cells
Pancreatic juice is also mixed with __ produced from the ____, before it enters the duodenum.
bile, liver
The liver produces ____, which does not contain any digestive _____. However, it helps to ___ ___, and neutralizes stomach acid through ___ like the pancreas
bile, enzymes, emulsify fats, bicarbonate
Bile is stored in the __ ___. It flows out of the _ ___ when it is time to be released, which merges with the __ ___ ___ into the __ __ ___, which in turn merges with the __ ___. From there, bile is secreted into the duodenum through the __ ____ ___
gall bladder, cystic duct, common hepatic duct, common bile duct, pancreatic duct, ampulla of vater
When fats move through the digestive system, it is exposed to a lot of ___, and end up ___ together into large spheres. bile ___ the fats which breaks it up into smaller pieces and increases the __ __ for lipases to work on. People with defects in bile production are often ___ of digesting fats
water, clump, emulsifies, surface area, incapable
The liver also _____ and ___ harmful substances such as toxins and alcohol from the blood, and ___ them. The liver also contains ___ cells, which are specialized macrophages in the liver that identify and remove pathogen in the __ that pass through the liver
detoxifies, filters, excretes, Kupfer, blood
The liver also stores ___ as needed for blood cell production as well as vitamins __, __ and ___
iron, A, D, B12
The kupfer cells can also destroy ___ ___ and the __ that is contained within them
irregular erthrocytes, hemoglobin
The liver also maintains normal __ __ levels, as it stores glucose in the form of ____ when it is high, and break it back down to glucose when levels are low
blood glucose, glycogen
The liver can also convert excess __- and __ into fat
carbohydrates, proteins
The liver also plays a role in the metabolism of proteins. it can synthesize __ __ and ___ amino acids. It removes the -___ group, from amino acids, and converts it to ____, which is sent to the kidneys to be excreted.
plasma proteins, nonessential, amine, urea
The large intestine which is also called the ____, receives chyme from the __ __, which is the passageway from the small to the large intestine. The large intestine mostly functions to absorb __ and ____.
colon, ileocecal valve, water, electrolytes
There are 4 parts to the large intestine:, the ___, ___ ___ and __ ___
ascending, transverse, descending, sigmoid colon
The pouch like opening to the large intestine
Cecum
The ___ is a projection from the cecum that functions to hold __ __ and a reservoir of healthy __ ___ in humans. In herbivores, this structure contains the bacteria that digest ____, which gives them the ability to digest plant __ ___>
appendix, immune cells, gut bacteria, cellulose, cell walls
At the end of the large intestine is the _____ which forms feces, that is excreted through the __ ___. Malfunction of the large intestine results in improper ____ absorption and thus can lead to ___
rectum, anal canal, water, diarrhea
The large intestine also contain ______ that are __ in the large intestine, These bacteria synthesize vitamin ___ and ___ that the large intestine absorbs
e. coli, symbiont, k, b12
the microorganisms living throughout your digestive tract
gut microbiome
The gut microbiome assist in ___ of compounds we are unable to digest on our own, provide _ ___, by competing against pathogens in the __ __, and they allow for the __ and ___of key nutrients. The extended use of ____ can lead to vitamin deficiency, as they kill bacteria indiscriminately
digestion, immune protect, gut living, synthesis, absorption, antibiotics
secretin is produced by the cells of the ____, and stimulates the release of ____ from the pancreas, which neutralizes the __ of chyme entering the small intestine
duodenum, bicarbonate, acidity
____ or CCK, is released by the cells of the duodenum when there is the presence of __ ___ and __ __ It stimulates the pancreas to stimulate __ __ and the gall bladder to release ___. It also slows _ ___, which means it slows the passage of food from the stomach to the small intestine, giving more __ to digest food and prevent from ___ the intestine with too many nutrients too quickly
cholecystokinin, amino acids, fatty acids, digestive enzymes, bile, gastric motility, time, overloading
_ ___ ___ is a hormone secreted by cells in the small intestine in response to ___, fats and ___. It stimulates ___ release, and mildly inhibits ___ ___ and ___
gastric inhibitory peptide, glucose, proteins, insulin, gastric secretion, motility
____ is a hormone that is primarily secreted by the pancreas. This ___ the secretion of most digestive hormones like gastrin, secretin and ___. It also decreases __ __
somatostatin, inhibits, CCK, gastric motility
The hormone ___ stimulates hunger when the body detects a decrease in __ ___.
ghrelin, body mass
____ suppresses hunger when the body senses an increases in body fat
leptin
__ ____, ____ and ___ all suppress the appetite
peptide YY, insulin, epinephrine
