GI Anatomy must knows

Question 1

Describe innervation of the tongue muscles

Answer 1

all of the tongue muscles are innervated by CNXII (hypoglossal) except the palatoglossus which is innervated by CNX - (vagus)

Question 2

what are constrictor muscles of the pharynx

Answer 2

the external layer of pharyngeal muscles, innervated by CNX

Question 3

What is the innervation of the inner longitudinal muscles

Answer 3

CNIX and X. Stylopharyngeus us the only muscle innervated by CNIX.

Question 4

Describe the innervation involved in the gag reflex

Answer 4

sensory limb - CNIX
motor limb - CNIX + CNX

Question 5

What is the innervation of the tongue

Answer 5

anterior two thirds
General sensory - CNV3
Special sensory (taste) - CNVII

posterior third
general and special sensory - CNIX

Question 6

What is the innervation of the muscles opening and closing the jaw

Answer 6

CNV3 - the mandibular division of the trigeminal nerve

Question 7

what muscles are involved in jaw closing

Answer 7

masseter, temporalis, medial pterygoid

Question 7

what are the muscles involved in jaw opening

Answer 7

lateral pterygoid

Question 7

describe the location of the pain associated with appendicitis

Answer 7

starts as a dull ache around the umbillicus, then moves to become a localised sharp pain in the RIF due to irritation of the parietal peritoneum

Question 7

what are pterygoid plates a part of

Answer 7

the sphenoid bone

Question 7

describe parasympathetic innervation of the GIT

Answer 7

Vagus nerve - up to the distal end of the transverse colon.

Pelvic splanchnic nerves S2,S3,S4 - from the descending colon to the anal canal

Question 8

Is the liver an intraperitoneal organ

Answer 8

yes

Question 9

where do sympathetic nerves synapse directly onto

Answer 9

cells of the adrenal gland

Question 10

describe the visceral afferent nerve fibres of the gut

Answer 10

foregut - T6 to T9
midgut - T8 to T12
hindgut - T10 to L2

Question 11

What does the galbladder do

Answer 11

stores and concentrates bile

Question 12

describe the location of the coeliac trunk

Answer 12

it is the first branch of the abdominal aorta, at T12, level, and supplies the organs of the foregut

Question 13

where does the splenic artery run

Answer 13

along the superior border of the pancreas

Question 14

what does the spleen do

Answer 14

the spleen breaks down red blood cells to produce biliruben

Question 15

what ribs protect the spleen

Answer 15

ribs 9-11

Question 16

describe the blood supply to the stomach

Answer 16

right (from hepatic artery) and left (from coeliac trunk) gastric arteries. Right (from gastroduodenal branch of hepatic artery) and left (from splenic artery ) gastro-omental arteries)

Question 17

what ribs protect the liver

Answer 17

ribs 7-11

Question 18

what are the 4 liver lobes

Answer 18

right, left, caudate, quadrate

Question 19

what artery supplies the gallbladder

Answer 19

cystic artery

Question 20

where are the hepatorenal and subphrenic recesses

Answer 20

within the greater sac

Question 21

what does the portal triad consist of

Answer 21

hepatic portal vein, hepatic artery and common bile duct

Question 22

what forms the ampulla of vater

Answer 22

the joining of the pancreatic duct and the bile duct

Question 23

describe the blood supply of the pancreas

Answer 23

mainly pancreatic branches of the splenic artery, but also from superior (from gastroduodenal branch of hepatic artery) and inferior (from SMA) pancreatoduodenal arteries

Question 24

is the duodenum intraperitoneal

Answer 24

the first part is, the other 3 parts are retroperitoneal

Question 25

where are paracolic gutters found

Answer 25

in the greater sac of the peritoneal cavity

Question 26

where is the appendiceal orifice located

Answer 26

on the posteromedial wall of the caecum, a third of the way between right ASIS and the umbillicus. This corresponds to mcburneys point

Question 27

where does the abdominal aorta bifurcate into the common iliacs

Answer 27

L4

Question 28

What is the main anastomosis in the large intestine called

Answer 28

the marginal artery of drummond

Question 29

describe blood supply to the rectum and the anal canal

Answer 29

hindgut part - superior rectal artery from IMA somatic part (below the pectinate line) - middle and inferior rectal arteries from the internal iliac artery

Question 30

Name the 3 important sites if postal systemic anastomoses

Answer 30

distal end of the oesophagus, skin around the umbilicus, rectum / anal canal

Question 31

what muscle makes up the pelvic floor

Answer 31

levator ani

Question 32

where does the sigmoid colon become the rectum

Answer 32

rectosigmoid junction, anterior to S3.

Question 33

Where does the rectum become the anal canal

Answer 33

the tip of the coccyx

Question 34

what are the 3 muscles associated with the levator ani

Answer 34

iliococcygeus, pubococcygeus, puborectalis

Question 35

describe the nerve supply to levator ani

Answer 35

branch of the sacral plexus, S3, S4 Pudendal nerve (S2, S3, S4)

Question 36

What does the pudendal nerve do

Answer 36

stimulates contraction of the external anal sphincter - S2, S3, S4 keeps the pelvis to the floor

Question 37

where do inguinal ligaments attach

Answer 37

between ASIS and pubic tubercle

Question 38

what is the deep ring

Answer 38

the midpoint of the inguinal ligament

Question 39

what is a direct inguinal hernia

Answer 39

a bit of peritoneum is forced through the posterior wall of the inguinal canal, and DIRECTLY OUT OF THE SUPERFICIAL RING.

Question 40

what is an indirect inguinal hernia

Answer 40

A bit of peritoneum us forced through the DEEP, into the inguinal canal, then OUT OF THE SUPERFICIAL RING