Digestive system

Question 1

function of the digestive system

Answer 1

digest food
absorb nutrients and h2o
immunological

Question 2

4 main division and their responsibilities

Answer 2

esophogus : Conducts food from oral cavity to stomach
stomach: Fragmentation of food and Initiates digestion
small intestine : Digestion is completed and Main absorption occurs
LI:Water absorption to reduce liquid content of solids. A holding chamber for feces prior to defecation via the anal canal

Question 3

4 Layers of the GI

Answer 3

Mucosa, submucosa, muscularis externa, adventitia

Question 4

main components of the Mucosa

Answer 4

Lining Epithelium:Invaginates to form mucosal glands.
Submucosal glands.

Lamina Propria:Blood and lymph vessels and Loose connective tissue – lamina propria. Lymphoid cells and nodular tissue
Muscularis Mucosa:
Several layers of smooth muscle cells

Question 5

Submucosa

Answer 5

Layer of dense irregular connective tissue supporting the mucosa.

Question 6

muscularis extera : inner outer layer function

Answer 6

Inner circular layer contracts to reduce the size of the lumen.

The outer longitudinal layer contracts to shorten the tube.

Action of the two layers at right angles is the basis of peristaltic contraction.

Question 7

ganglion of the muscularis externa

Answer 7

Parasympathetic ganglion cells in the muscularis externa, form Meisner’s and Auerbach’s plexus

Question 8

where can skeletal muscle be found in GI tract

Answer 8

upper esophagus and anal sphincter

Question 9

when is the adventia referred to as serosa ?

Answer 9

Outermost layer of connective tissue

When lined by mesothelium is referred to as serosa

Question 10

muscularis externa of the esophagus types of tissue?

Answer 10

Skeletal muscle in upper third
Mixed in middle third
Smooth muscle in lower third

Question 11

pyloric glands of the stomach

Answer 11

deeper pits than the cardia and fundus

glands are lined with mucous cells

Question 12

parietal cells ?

Answer 12

secrete HCL and intrinsic factor

Question 13

how do parietal cells increase in the secretion of HCl acid

Answer 13

Parasympathetic stimulation and the hormone gastrin leads to fusion of the tubulo-vesicles with the canaliculi, and an increase in the secretion of HCl acid

Question 14

___ is a compound that increases the effects of the fusion of tubulo vesicles and canaliculi

Answer 14

histamine

Question 15

Bicarbonate Secretion by Mucosal Epithelium

Answer 15

Bicarbonate is released by parietal
they enter fenestrated capillaries
diffuse across surface increasing pH
they buffer HCL and protect mucous cells

Question 16

cheif cell function

Answer 16

sectete pepsinogen

Question 17

mucous cells ?

Answer 17

secrete mucinogen to protect the epithelial lining of the stomach

Question 18

enteroendocrine cells

Answer 18

secrete gastrin, gastric inhibitory peptide (GIP)

Question 19

gastrin hormone?

Answer 19

produced by stomach

gastric acid secretion and stimulate HCL and insulin secretion , stimulate gastric motility and growth of mucosal cells

Question 20

chloecystokin

Answer 20

produced by duodenum and jejunum
stimulate bile release from gallbladder, pancreatic enzyme secretion and pancreatic bicarbonate secretion
inhibits gastric emptying

Question 21

secretin

Answer 21

produced by duodenum
insulin and pancreatic bicarbonate secretion
inhibit gastric acid secretion

Question 22

Gastric inhibitory peptide

Answer 22

produced by Duodenum Jejunum
insulin release
inhibit Gastric acid secretion

Question 23

4 degrees of folding that amplify total surface area of the SI

Answer 23

Plicae:evagination of the mucosa and submucosa
villi: evagination of the mucosa
glands or crypts of lieburkuhn
microvilli

Question 24

how is gastric emptying controlled ?

Answer 24

by chloecystokin that acts on pyloric sphincter

Question 25

• Paneth cells –

Answer 25

• Paneth cells – found in small intestine only; secrete defensins, lysozyme and TNF-alpha

Question 26

• Peyer’s patches –

Answer 26

found in the ileum; lymphoid follicles with germinal centers lined by specialized antigen presenting M cells

Question 27

Digestion & Absorption of Carbohydrates | in the Small Intestine ?

Answer 27

oligosaccharidases are present in brush bored and convert oligo and disacchardies to mono for absorption

Question 28

SGLT-1

Answer 28

Used in carb digestion of SI | It is a Na+ dependent carrier that allow glucose and galactose to enter the enterocyte

Question 29

Lacteals

Answer 29

are Involved in the Uptake & Transport of Lipoproteins and Chylomicrons

Question 30

apoptosis of epithelial cells of SI occurs on

Answer 30

villi

Question 31

crypts of lieburkuhn are responsible for ?

Answer 31

being one of 4 folding degrees and AND where mitosis od stem cells happen

Question 32

Outer longitudinal layer of the muscularis externa of LIconverts to become ??

Answer 32

Outer longitudinal layer of the muscularis externa converts to become three (3) taeniae coli: longitudinal bands of smooth muscle

Question 33

Main function of mucosa of LI is

Answer 33

Main function of mucosa is absorption of water, sodium, | vitamins and minerals

Question 34

LI has no villi but has

Answer 34

crypts of Liebrukugn

Question 35

most abundant lining cell in LI

Answer 35

goblet cells

Question 36

crohn's disease

Answer 36

``` Chronic inflammatory disease Affects entire gut wall; ulcerations and lymphoid infiltrates. Diarrhea, wasting, pain Granulomas can obstruct bowel Bowel can form fistulas or perforate ```

Question 37

Ulcerative colitis

Answer 37

Ulcerative colitis is similar to crohn's, only ulcers affect entire colon instead of just patches.