GI 1: Anatomy and Histology

Question 1

what are the 2 overall homeostatic functions of the GI tract?

Answer 1

1. process food into digested macro/micronutrients and distribute them to cells
2. maintain body water and electrolyte balance

Question 2

the overall homeostatic functions of the GI tract are achieved by ___(#) processes

Answer 2

6

Question 3

what are the 4 basic processes of the GI tract?

Answer 3

1. motility
2. digestion
3. secretion
4. absorption

Question 4

where does motility occur?

Answer 4

esophagus, stomach, small I and large I

Question 5

where does digestion occur?

Answer 5

stomach, small I

Question 6

where does secretion occur?

Answer 6

mouth, stomach, small I , liver and pancrea

Question 7

where does absorption occur?

Answer 7

mostly in small I, but also in stomach and large I

Question 8

the digestive tract includes what 7 structures?

Answer 8

1. oral cavity
2. pharynx
3. esophagus
4. stomach
5. small intestie
6. large intestine
7. anus

Question 9

what are the 3 parts of the small intestine?

Answer 9

duodenum, jejunum; ileum

Question 10

what is the function of the accessory organs to the GI tract?

Answer 10

secrete fluids and other substances into the GI tract

Question 11

what accessory organs secrete in the mouth?

Answer 11

salivary glands

Question 12

accessory glands in the ___, ___ and ____ secrete into the small intestine

Answer 12

liver, gallbladder, and pancreas

Question 13

what are the 4 main layers of the digestive tissue?

Answer 13

1. mucosa
2. submucosa
3. muscularis externa
4. serosa

Question 14

what is contained in the mucosa layer?

Answer 14

epithelium, lamina propria, muscularis mucosae

Question 15

what is contained in the muscularis externa layer?

Answer 15

longitudinal muscle and circular muscle

Question 16

what is contained in the serosa layer?

Answer 16

connective tissue and epithelium

Question 17

where are endocrine cell located in the gi tract?

Answer 17

along the epithelium that is exposed to the gut lumen

Question 18

where are mucous cells located in the GI tract?

Answer 18

along the epithelium exposed to gut lumen

Question 19

endocrine secrete into ___

Answer 19

internal environment

Question 20

exocrine secrete into ___

Answer 20

external environment

Question 21

epithelium cells are joined by ___ that prevent leaky gut

Answer 21

tight junctions

Question 22

what are the 3 major functions of the mucosa and the locations they perform these functions?

Answer 22

1. secretion (stomach)
2. protection (mucous)
3. absorption (small )

Question 23

what type of wbc are located w/i the lymph nodules of the GI tract to help prevent disease?

Answer 23

GALT

Question 24

the epithelium of the GI tract has what 2 types of sensory receptors?

Answer 24

chemical and mechanical

Question 25

what is the function of the simple columnar epithelium cells>

Answer 25

absorb nutrients (microvili)

Question 26

what is the function of enteroendocrine cells?

Answer 26

secrete hormones

Question 27

the muscularis mucosae has ____ that increase SA and digestion / absorption

Answer 27

high # of folds

Question 28

what is the main function of the submucosa?

Answer 28

elasticity

Question 29

the BV and lymph nodes are ____ (smaller/larger) in the submucosa

Answer 29

larger

Question 30

the submucosa is formed of ___ and ___ tissue

Answer 30

elastic and connective

Question 31

there are ___, ___ and ____ found in the submucosa. As well, there are ___ in all organs except the esophagus and stomach

Answer 31

glands; blood vessels; lymphatic vessels; submucosal plexus

Question 32

in the mouth, upper esophagus, pharynx, external and anal spincters have what layer of muscles (exception to muscularis smooth muscles)

Answer 32

skeletal muscles

Question 33

the stomach has ___ layers of smooth muscle that include a ____layer

Answer 33

3; intermediate oblique

Question 34

what is the function of the circular muscularis

Answer 34

reduce diameter

Question 35

what is the function of the longitudinal layer of muscularis?

Answer 35

shorten tube

Question 36

smooth muscle works as a single __

Answer 36

unit

Question 37

cells in the GI tract are electrically connected to neighbouring cells by ____

Answer 37

gap junction

Question 38

what are the 3 benefits of gap junctions in the GI tract?

Answer 38

1. low resistance to ion movement between cells
2. quick spread of electrical signals
3. simultaneously contrcation of cells

Question 39

the enteric nervous system is made of the __ and ___

Answer 39

submucosal plexus and the mysenteric plexus

Question 40

what is considered the “brain of the gut”

Answer 40

enteric nervous system

Question 41

the submucosal plexus is located in the

Answer 41

submucosa

Question 42

the myenteric plexus is located in the __

Answer 42

muscularis externa

Question 43

the myenteric plexus controls ___

Answer 43

motility

Question 44

the submucosal plexus controls ___

Answer 44

secretion

Question 45

the longitudinal and circular smooth muscle of the muscularis externa are stimulated by ___ neurons from the ___ plexus

Answer 45

motor; myenteric

Question 46

endicrine cells and exocrine cells are stimulated by ___ neurons from the ___ plexus which are stimulated by __ neurons from the ___ plexus

Answer 46

motor; submucosal; interneuron; myenteric

Question 47

the serous layer is made of ___ tissue

Answer 47

connective

Question 48

what is the function of the serosa?

Answer 48

produce serous fluid to lubricate the exterior of the highly motile organ

Question 49

the mucosal epithelium is stimulated ny ___ neurons fom the ___, ___ and _____

Answer 49

sensory; myenteric, submucosal; ANS to CNS neurons