digestive system review pt. 1
what are the 3 major sections of the large intestine?
cecum, colon, rectum
peristalic contractions
involuntary muscle contractions that assist in digestion involving longitudinal muscles
name the 3 layers of muscle found in the stomach
longitudinal muscularis, circular muscularis, oblique muscularis
name 2 functions of the liver
1) Removing bacteria and old red blood cells 2)detoxifying blood from drugs and poisons 3)storing glycogen and producing fats 4)manufacturing proteins storing iron and copper 5)secreting bile
peristalsis process
1. bolus of food arrives in digestive system 2. circular muscles contract behind bolus 3. longitudinal muscles ahead of bolus contract 4. contraction in circular muscle layer forces bolus forward
what is saliva consisted of?
99% water, mucus, amylase(lowers starch) , lysozymes(kills bacteria), antibodies
chyme
Partially digested, semiliquid food mixed with digestive enzymes and acids in the stomach.
how many teeth does a toddler have? how many teeth does an adult have?
a toddler has 20 teeth. an adult has 32
why does antibiotic usage often cause vitamin deficiencies?
antibiotics kill beneficial bacteria in the large intestine which usually forms vitamins B and K
what portions of the colon are identified in the large intestine?
ascending colon, transverse colon, descending colon
lipids are broken down by which enzymes? because lipids are insoluble they must be _______ BEFORE being broken down.
bile salts, pancreatic lipase. emulsified
what is the pulp cavity?
blood vessels and nerves
peptidase and enterokinase
break down proteins
maltase, sucrase, lactase
break down sugars
which teeth tear and pierce food?
canines (cuspids)
what two circular rings of muscle act as gatekeepers for the stomach?
cardiac sphincter and pyloric sphincter
how do catabolism an anabolism differ?
catabolism is the breaking down of complex molecules to release energy and anabolism is the opposite process
are salivary glands responsible for mechanical or chemical digestion? what molecules do they break down?
chemical digestion; they break down straches/carbohydrates
mastication is commonly called
chewing
which layer is dentin?
dentin is the third layer (light brown area)
name 3 portions of the small intestine starting with the most superior
duodenum, jejunum, ileum
What covers the dentin?
enamel on the crown and cementum on the root
secretin and cholecystokinin(CCK)
enzymes that stimulate the digestive juices of the pancreas, liver, and gallbladder
which is voluntarily controlled, the internal or external anal sphincter?
external anal sphincter
name the 4 regions of the stomach
fundus, body, cardiac region, pyloric sphincter
what provides a seal around the tooth?
gingivae (gum)
what are the 2 types of muscle contractions found in the large intestine? how do they differ?
haustral contractions & mass movements. haustral contractions are shorter in duration and less powerful.
name the 3 macronutrients required by the body
lipids, carbohydrates, proteins (water is also considered a macronutrient)
which teeth are used for grinding?
molars (tricuspids)
what 3 cells are involved with gastric juices?
mucous cells, chief cells(secrete pepsinogen), parietal cells(secrete HCL)
name 3 types of cells in the stomach that secrete gastric juices
mucous cells, parietal cells, chief cells
the small intestine primarily absorbs ______ while the large intestine absorbs ______.
nutrients; water
proteins are broken down by which enzymes? in this process, the proteins are broken into individual _______ acids.
pepsin, pancreatic enzymes, brush border enzymes. amino
what process is responsible for directing food through the esophagus?
peristalsis or peristaltic contractions
haustra
pouches that form in the large intestine giving it its lumpy appearance "corn".
which teeth are used for crushing?
premolars (bicuspids)
carbohydrates are broken down by which enzymes? what is this process called?
salivary amylase, pancreatic amylase, brush border enzymes. process is called cellular respiration
name 2 functions of the pancreas
secreting digestive enzymes and sodium bicarbonate, secreting hormones (insulin)
why is segmentation of chyme in the small intestine important?
segmentation slows down the movement of chyme allowing for better absorption
what are the four layers of the alimentary canal from superficial to deep?
serosa, muscularis, submucosa, mucosa
deglutition is also called
swallowing
name 2 structures in the digestive system responsible for mechanical digestion
teeth, stomach
which are the incisors and what is their function?
the blue are incisors, they are responsible for cutting food.
what are the 2 phases of deglutition?
the buccual phase & the pharyngeal-esophageal phase
how do the liver and gall bladder work together?
the liver produces bile and the gall bladder stores it for release into the small intestine
what finger-like projections are found in the small intestine and what is their function?
villi, they increase surface area for more efficient nutrient absorption
how do vitamins and minerals differ?
vitamins are organic molecules required in small amounts and minerals are inorganic molecules required in small amounts.
what are rugae?
wrinkles in the mucosa of the stomach to help it stretch
