Gastrointestinal system 1

Question 1

what are the roles of the oral cavity

Answer 1

mastication and lubrication
gustation
limited chemical digestion
speech

Question 2

hard palate vs soft palate

Answer 2

hard is further forward

Question 3

what is digested in the limited chemical digestion in the oral cavity

Answer 3

glucose and lipids

Question 4

what epithelium is the oral mucosa lined with

Answer 4

stratified squamous

Question 5

oral vestibule

Answer 5

the space between lips and gums/teeth
salivary secretion ducts
frenulum connects lip to gingiva

Question 6

role of the uvula

Answer 6

prevents food from entering the nasal cavity

Question 7

roles of the tongue

Answer 7

mechanical digestion and manipulation of food
sensory: gustation and temperature
lubrication of bolus

Question 8

how many teeth do humans have

Answer 8

20 during development
32 after development

Question 9

salivary glands locations and secretions

Answer 9

parotid gland: parotid duct - vestibules, serous secretion (amylase)

sublingual gland: under the tongue, secretes mucous

submandibular gland: beneath the jaw, serous and mucous secretions

Question 10

roles of saliva

Answer 10

lubricate and moisten bolus
limited digestion
dissolving chemicals for gustation
buffer
controls bacterial populations (antibodies and lysosomes)

Question 11

parts of the pharynx
what epithelium do they have

Answer 11

nasopharynx - pseudostratified ciliated columnar epithelium

oropharynx - stratified squamous epithelium

laryngopharynx - stratified squamous epithelium

Question 12

stages of deglutination and the structures involved in each

Answer 12

buccal phase: soft palate, tongue, uvula

pharyngeal phase: pharynx muscle, epiglottis, uvula

oesophageal phase: oesophagus, involuntary - approaching bolus triggers opening of lower oesophageal sphincter

Question 13

where is mucosal epithelium present in the GIT
what type of epithelium is it

Answer 13

oral cavity
pharynx
oesophagus
anal cavity

stratified squamous epithelium

Question 14

where is simple columnar epithelium present in the GIT

Answer 14

stomach
small intestine
large intestine

Question 15

lamina propria

Answer 15

layer of connective tissue located beneath mucosal epithelium

contains blood vessels, muscles, lymph vessels and nerves

Question 16

muscularis mucosa

Answer 16

thin layer of smooth muscle and elastic fibres that separates the mucosa from the submucosa

deepest layer of mucosa

inner circular layer and outer longitudinal layer
regulates shape of the lumen

Question 17

submucosa

Answer 17

connective tissue binding mucosa and muscular layer

contains blood and lymph vessels and nerves (submucosal plexus)

exocrine glands

Question 18

muscular layer

Answer 18

muscularis propria
smooth muscle coordinated by the ENS myenteric plexus

inner circular layer
outer longitudinal layer

Question 19

serous membrane

Answer 19

outermost connective tissue layer
adventitia in structures not lined with visceral peritoneum

Question 20

what causes spontaneous depolarisation of the muscularis mucosa and muscular layer

Answer 20

pacesetter cells

Question 21

peristalsis

Answer 21

rhythmic waves of contraction
propulsion process to move bolus forward

Question 22

segmentation

Answer 22

contraction of intestines to churn, fragment and mix
no pattern and does not move in any direction

Question 23

mucosa of oesophagus

Answer 23

stratified squamous epithelium

Question 24

submucosa of oesophagus

Answer 24

contains oesophageal glands

Question 25

muscular layer of oesophagus

Answer 25

superiorly skeletal and transitions to smooth inferiorly

Question 26

role of the adventitia of the oesophagus

Answer 26

anchors to posterior body wall

Question 27

gastro-oesophageal reflux disease

Answer 27

heartburn, chest pain, difficulty swallowing, regurgitation

can lead to ulcer, strictures, Barret’s oesophagus

Question 28

ascites

Answer 28

abnormal fluid build up in the peritoneum

Question 29

what are mesenteries
what are its roles

Answer 29

double sheets of peritoneal membrane that attaches the intestine to the wall around the stomach area and holds it in place

prevents volvulus: twisting of a loop of intestine around itself and the mesentery that supplies it
routes for blood, lymph and nerve supply

Question 30

greater omentum

Answer 30

pouch of adipose tissue
provides padding and insulation

Question 31

lesser omentum

Answer 31

mesentery that supplies stomach and liver

Question 32

falciform ligament

Answer 32

mesentery that supplies liver and abdominal wall

Question 33

mesentery proper

Answer 33

mesentery that supplies duodenum and pancreas

Question 34

mesocolon

Answer 34

mesentery that supplies colon and rectum
attached to abdominal wall

Question 35

what are the layers of the mucosa

Answer 35

mucosal epithelium
lamina propria
muscularis mucosae

Question 36

what is the function of rugae in the stomach

Answer 36

allow for expansion

Question 37

muscular layer of the stomach

Answer 37

inner circular and longitudinal layers
extra oblique layer overlaying the mucosa

Question 38

regions of the stomach

Answer 38

cardia: oesophagus entry
fundus: superior region
body
antrum: inferior region
pylorus: entry to duodenum

Question 39

role of the cardia

Answer 39

entry point for the stomach
contains mucous gland that protects oesophagus

Question 40

epithelium of stomach

Answer 40

simple columnar epithelium
gastric pits that produce secretory sheet of alkaline mucous

Question 41

gastric glands and their secretions

Answer 41

fundus: acids and enzymes
parietal cells: intrinsic factor (B12) and indirect HCl
chief cells: pepsinogen
pyloric: mucous, gastrin

Question 42

gastritis

Answer 42

inflammation of the lining of the stomach (can lead to cancer)

stomach discomfort, nausea, vomiting, burning sensation, bloody stool