ch 23 digestive system p1

Question 1

the digestive system associated terms

Answer 1

GI tract and alimentary canal

Question 2

6 functions of digestive system

Answer 2

ingestion, movement, mechanical breakdown, digestion, absorption, defecation

Question 3

movement in digestive system

Answer 3

food propelled through peristalsis, ensures things don’t move backwards

Question 4

mechanical breakdown in DS

Answer 4

food broken down to smaller pieces to increase digestion efficiency, inc SA of food

Question 5

digestion in DS

Answer 5

enzymes breakdown complex foods to building blocks. catabolic process of creating monomers

Question 6

absorption inDS

Answer 6

building blocks are passed from DS to blood or lymph

Question 7

membranes of the DS

Answer 7

peritoneum, mesentery

Question 8

peritoneum

Answer 8

serous membrane covers organs of abdominopelvic cavity. visceral covers organs, parietal clings to body wall, peritoneal cavity is the fluid filled space between visceral and parietal

Question 9

why do we need the peritoneal cavity

Answer 9

prevents friction from organ to organ or organ to body. ensures no damage

Question 10

mesentery

Answer 10

double layer peritoneum extends from digestive organs to body wall. holds organs in place provides blood passage as well as nerve n lymph to digestive organs. fat storage too

Question 11

alimentary canal

Answer 11

portion of digestive system that forms lung tube out of body. mouth, pharynx, esophagus, stomach, small intestine, large intestine. also has associated glands.

Question 12

alimentary canal layers, from inner to outer

Answer 12

Epithelia, lamina propria, muscularis mucosae, mucosa, submucosa, muscularis externa, serosa

Question 13

mucosa of alimentary canal

Answer 13

innermost, has epithelia lamina propria and muscularis mucosa.

Question 14

epithelia of mucosa

Answer 14

simple columnar mostly, secretes mucous and digestive enzymes, hormones, absorptive surface. stratified squamous in anus and mouth and esophagus.

Question 15

lamina propria of mucosa

Answer 15

loose areolar connective tissue, vascularized to substances can get absorbed here, MALT tonsils and appendix

Question 16

muscularis mucosae

Answer 16

smooth muslce cells, creates movement to increase digestion and secretion. secretes digestive enzymes and hormones

Question 17

submucosa

Answer 17

superficial to mucosa, areolar connective tissue with elastic fibers, rich blood supply Nd nerve fibers serving GI tract

Question 18

muscularis exterrna

Answer 18

generates movement in GI tract like a worm. has circular and longitudinal Layer. they DO NOT contract at the same time.

Question 19

circular layer of muscukaris external

Answer 19

constricts and fibers of muscle are around circumference constrict, long and small

Question 20

longitudinal layer of muscularis external

Answer 20

contraction makes tube wider, along whole length widens and shortens

Question 21

alternating contractions of the circular and longitudinal layers allows for

Answer 21

waves called peristalsis, if they wrnt at same time, tube would do nothing. no movement and as one relaxes other goes

Question 22

sphincters

Answer 22

thickening in muscularis externa, controls movement of one alimentary organ to another, prevents back movement of ingested food.

Question 23

serosa

Answer 23

outermost layer, has visceral peritoneum

Question 24

in organs NOT in abdominopelvic cavity what is serosa

Answer 24

adventitia, which holds the organs in place with dense connective tissue.

Question 25

splanchnic circulation

Answer 25

bloody supply to digestive organs, arteries branch off aorta and hepatic portal circulation.

Question 26

what do arteries do in splanchnic circulation

Answer 26

branch off celiac trunk that serve spleen liver and stomach, spleen is not digestive directly.

Question 27

hepatic portal circulation

Answer 27

collects nutrient rich blood draining from digestive organs and transport to liver. WHY? to be filtered, veins don't go to heart with portal system so many nutrients absorbed to prevent sensitive organs from bad exposure

Question 28

innervation of the digestive system consists of the

Answer 28

enteric NS, the nerve supply to alimentary canal. NOT CNS. called our second brain.

Question 29

enteric nervous system consists of two major intrinsic nerve plexuses

Answer 29

submucosal, found in submucosa to control secretions and absorptions myenteric, found between circular and longitudinal muslce layers to control muslce tone in GI tract

Question 30

function of the instrinsic nerve plexus'

Answer 30

both plexuses supply walls of entire GI tract and help regulate motility. intrinsic is built in.

Question 31

long reflex of enteric NS

Answer 31

initiated by stimuli inside and outside the GI tract. involves CNS and extrinsic autonomic nerve. sympathetic stimulation- inhibits gastric activity, slows digestion during dight or flight. parasympathetic stimulation- stimulates enhanced gastric activity during rest

Question 32

short reflex of enteric NS

Answer 32

mediated entirely by enteric NS in response to GI tract stimuli. ex; peristalsis.

Question 33

the mouth

Answer 33

part of alimentary canal, composed of several skeletal muscles, for ingestion and movement. has hard and soft palate.

Question 34

hard palate

Answer 34

rigid and ribbed surface on roof of mouth, hooks break down food when tongue pushes against it

Question 35

soft palate

Answer 35

soft and mobile surface behind hard palate, has uvula which protects from soft palate and helps close off nasopharynx

Question 36

what is function of soft palate and uvula

Answer 36

both help close nasopharynx as u swallow

Question 37

the tongue

Answer 37

accessory organ, bundles of skeletal muscle, has intrinsic and extrinsic muscles

Question 38

instrinsic tongue muscles

Answer 38

confined within tongue, not bone attached. allows tongue to change space

Question 39

extrinsic muscle of tongue

Answer 39

origin of muslce is found on bone, allows tongue to change position in the mouth. ex moving side to side or sticking out

Question 40

salivary glands of the mouth

Answer 40

accessory organ, has saliva which uses IgA to cleanse, dissolves food chemicals for taste, moistens food, and contains digestive enzymes to breakdown stuff

Question 41

salivary amylase

Answer 41

a digestive enzyme of the salivary glands, begins digestion of STARCHY foods

Question 42

lingual lipase

Answer 42

another digestive enzyme of the salivary glands, begins lipid breakdown and is not as important

Question 43

3 major salivary glands

Answer 43

parotid (largest, from roof of mouth), submandibular (opens at floor of mouth under tongue), sublingual (smallest, directly under tongue, really important has 10-20 dif ducts)

Question 44

teeth

Answer 44

accessory glands of alimentary Canal, tear and grind food to smaller pieces while chewing

Question 45

deciduous teeth

Answer 45

baby teeth or milk teeth, 20, shed in early childhood 6 mo to 2 yrs

Question 46

permanent teeth

Answer 46

well eventually replace baby teeth that falll out during adolescence. 32 of them.

Question 47

3 teeth types

Answer 47

incisors- cutting canines- tearing premolars and molars- grinding

Question 48

primary dentition formula

Answer 48

2I, 1C, 2M divided by 2I,1C, 2M times 1. no premolars

Question 49

permanent dentition formula

Answer 49

2I, 1C, 2PM, 3M divided by 2I, 1C, 2PM, 3M times

Question 50

main regions of teeth

Answer 50

crown, exposed portion and enamel tough mineral substance covers exposed tooth surface root, portion embedded in jawbone anchored to periodontal ligament

Question 51

hardest substance made by body

Answer 51

enamel, acidic foods eat at it, and cavity destroys it, we don't produce more once gone.

Question 52

teeth are composed of what

Answer 52

dentinm softer than enamel and absorbs shock

Question 53

what cell lays down dentin

Answer 53

odonotblast

Question 54

dentin surrounds what

Answer 54

the pulp cavity, which has connective tissue blood vessels and nerve supply

Question 55

pharynx

Answer 55

alimentary canal organ, contractions of muslce propels food to esophagus,.

Question 56

esophagus joins tummmm

Answer 56

joins stomach at cardiac orifice. collapsed when no food is there. cardiac sphincter can be found at where stomach and esophagus join

Question 57

function of cardiac sphincter

Answer 57

closes stomach off when no food enters thru esophagus, also prevents food from going back into esophagus

Question 58

4 stomach regions

Answer 58

cardia, fundus, body, pyloric portion.