lecture 17

Question 0

the glandar sturcture of the secretory function of the GI tract

Answer 0

mucous Gland , glandular pits(TUBULAR) , tubular glands, Acinar aveolar

Question 1

the secretory function of the GI tube

Answer 1

digestive enzymes to be secreted and secretion of mucus from mucus gland provide lubrication and protection

Question 2

single cell mucous gland

Answer 2

mucous cell( globlet cell) , it is found on the surface off the epithelium in the GI Tract, its function is to respond to irritation of the epithelium by the producing mucus, which acts as a protectant to the surface from excorination and digestion

Question 3

Glandular Pits(tubular )

Answer 3

this represents invagination of the epithelium into the submucosa , in the small intestine this pits is called the cryptes of lieberkihn

Question 4

Tubular Glands

Answer 4

In the stomach and upper duodenum

Question 5

Acinar(alveolar)

Answer 5

found in the salivary glands, pancreas, and liver, provided secretion for digestion or emulsificatin of food, In the GI tract these acini feed into a system that empty into the allimentary tract. this are exocrine glands

Question 6

Stimulation of the secretory Glands is by

Answer 6

presence of food, Autonomic nervous system, and hormones

Question 7

the presence of food in the gi tract activates

Answer 7

the enteric nervous system of the gut wall, there is tactile sensation, chemical irritation, and distention of the gut

Question 8

parasympathetic stimulation of gland

Answer 8

affects the rate of alimentary glandular secretion from the glands in the upper portion of the tract eg salivary gland, esophagus gastric glands, pancreas, brunner’s gland( duodenum). this is innervated by the by the glossopharyngeal and vagus nerve

Question 9

sympathetic stimulation of the secretory glands

Answer 9

cause moderate secretion by local gland, also resulting in constriction of blood vessels that supply the gland

Question 10

dual effect of sympathetic stimulation

Answer 10

sympathetic stimulation will cause increase in secretion, but if parasympathetic or hormonal stimulation is in effect, then it will reduce stimulation

Question 11

Hormones and stimulation of secretory glands

Answer 11

it regulates the volume and character of the secretion
the hormone are release from the GI mucosa in response to the presence of food
hormones are then absorbed into the blood and carried to the gland that will release secretion.

Question 12

1 step of secretion of organic substance

Answer 12

1. materials needed for formation of secretion must diffuse or be actively transported by the blood in the capillaries into the base of the glandular cell via merocrine secretion

Question 13

2 step of secretion of organic substance

Answer 13

mitochondria located in the glandular cells near its base uses oxidative energy to form ATP

Question 14

3 step of secretion of organic substance

Answer 14

atp and appropriate substance provided by the nutrient is used to synthesize organic substance. this occurs in the ER and Golgi complex.

Question 15

4th step of secretion of organic substance

Answer 15

the secretory material are transported through the tubules of the ER to the vesicle of the Golgi

Question 16

5th step of secretion of organic substance

Answer 16

In the Golgi material are modified and discharged into the cytoplasm in from of secretory vesicle, which are stored at the apex of the cell until stimulated

Question 17

——–stimulation causes water and salt to pass through the glandular cells

Answer 17

nervous stimulation

Question 18

the mechanism for the movement or secretion of water and electrolyte through the cell is known as

Answer 18

apical flush out

Question 19

apical flush out mechanism step 1

Answer 19

nerve stimulation affects the basal portion of the cell causing an active transport of cl- into the cell

Question 20

apical flush out mechanism step 2

Answer 20

the cell becomes more negative thus allowing for Na+ ion to move into the cell

Question 21

apical flush out mechanism step 3

Answer 21

excess positive and negative ione causes water to enter the cell, increasing cell volume and hydrostatic pressure( the cell swells)

Question 22

apical flush out mechanism step 4

Answer 22

the pressure in the cell causes the opening of secretory border flushing water, electrolyte, and organic substance out of the secretory end of the secretory glandular cell

Question 23

name the salivary glands

Answer 23

Parotid, submandibular, and sublingual gland. There are also small buccal glands

Question 24

name the types of salivary glands

Answer 24

serous secretion that contain ptyalin ( alpha amylase) | mucous secretion that contains mucin for lubrication and protection the GI tract surface.

Question 25

parotid secretes

Answer 25

serous secretion

Question 26

submandibular and sublingual secretes

Answer 26

both serous and mucus

Question 27

buccal gland secretes

Answer 27

mucus

Question 28

neural control of the the salivary gland and secretion is through

Answer 28

the parasympathetic nervous system by the superior and inferior salivatory nuclei in the brain stem

Question 29

salivatory nuclei

Answer 29

it is in the brain stem, juncture between medulla and pons,and are excited by both tastes and tactile stimuli from the tongue and mouth and pharynx inhibits or stimulates via nervous signal of CNS

Question 30

the major secretion of the esophagus is

Answer 30

mucous and aid with swallowing

Question 31

the esophagus is lined with

Answer 31

many simple mucous glands

Question 32

compound mucous gland are found

Answer 32

at the gastric end and to a lesser extent in the initial portion of the the esophagus

Question 33

the mucus secreted by the compound gland in the upper esophagus prevents

Answer 33

mucosa excoriation by the newly entering food

Question 34

compound glands near the esophagogastric junction functions

Answer 34

as a protection from digestion by acid gastric juices

Question 35

in addition to mucus-secreting cells, the stomach mucosa has to important type of tubular glands

Answer 35

oxyntic gland and pyloric gland

Question 36

oxyntic gland also called gastric gland secrete

Answer 36

HCL, pepsinogen ,intrinsic factor and mucus

Question 37

The pyloric gland secretes

Answer 37

mainly mucus for the protection of the the pyloric mucosa and it also secrete gastrin

Question 38

The oxyntic (gastric) gland is made up four cells

Answer 38

1 mucous cell--- secretes mainly mucus 2 chief cells( zymogenic )--- secrets pepsinogen 3 parietal cells--- secretes intrinsic factors and HCL 4. ECL( entrochromaffin-like cells) secrete hormone like material histamine .

Question 39

step 1 mechanism of the HCL secretion

Answer 39

cl- is actively transported into the lumen of the canaliculus then sodium is also actively transported into cytoplasm. this causes the cell to become more negative in the canaliculus , thus cause K+ to enter the cell and Na +, thus kcl enter the enter the canaliculus

Question 40

step 2 of the secretion of HCL

Answer 40

water dissociate in the cytoplasm to H+ and OH- , the H+ is secreted into the canaliculus in exchange for K ion by H+ K+ atpase, Na+ is also pump out by a na pump , thus resulting in the formation of HCL in the canaliculus , then secreted into lumen of the gland.

Question 41

step 3 of the secretion of HCL

Answer 41

water enters into the canaliculus via osmosis and the final secretion is water HCL

Question 42

step 4 of the secretion of HCL

Answer 42

finally carbon combines under the influence of carbonic anhydrase with hydroxyl ion to form bicarbonate, diffuses through the cell cytoplasm into the ECF in exchange for chloride ions that enter through the ecf then is later secreted

Question 43

intrinsic factor is essential for

Answer 43

The absorption of vitamin B12 in the ileum and is secrete by the parietal cells

Question 44

control of the chief cells

Answer 44

1. ANS controls the chief cells through the vagus nerve ( 10) 2. affected by the intrinsic nervous system ( plexuses) 3. Ph of the stomach 4. acetylcholine

Question 45

control of the parietal gland

Answer 45

1. main control is PNS( innveration of the mucous wall) 2. gastrin has a direct effect 3. histamine has an indirect effect

Question 46

brunner's gland

Answer 46

it is found in the duodenum of the small intestine and it functions to product alkaline mucus