GI anatomy 2

Question 1

Which nerve/s are the muscles of mastication supplied by?

Answer 1

Mandibular division of Trigeminal nerve= CN5 V3

V3- Mandibular divison

Question 2

Which of the muscles of mastication are used to close the mouth?

Answer 2

1. Temporalis
2. Masseter
3. Medial Pterygoid

Question 3

Which muscle of mastication is used to open the mouth?

Answer 3

Lateral Pterygoid

Question 4

Where does the Trigeminal nerve originate? (CNS part)

Answer 4

Pons

Question 5

Where is the intracranial part of the trigeminal course?

Answer 5

inferior to edge of Tentorium cerebelli

Question 6

Where is the base of the foramen part of the trigeminal course?

Answer 6

Sphenoid bone

Foramen ovale

Question 7

Where is the extra cranial part of the trigeminal course?

Answer 7

From foramen ovale to part of the body supplied

Question 8

Why are loose teeth or parts are a risk?

Answer 8

Choking hazard, aspiration risk

Question 9

What is aspiration? Why is it dangerous?

Answer 9

Inhalation of liquid or solid matter into lungs. Potential infection

Question 10

Which part of the CNS does the facial nerve come from?

Answer 10

Junction between pons and medulla

Question 11

Where is the intracranial part of the facial nerve

Answer 11

internal acoustic meatus (in posterior cranial fossa)

Question 12

Where is the base of the foramen part of the facial nerve?

Answer 12

Temporal bone

Question 13

Where is the extra cranial part of the facial nerve?

Answer 13

Stylomastoid foramen

Question 14

Facial nerve cranial number?

Answer 14

VII

Question 15

What is the Chorda Tympani? What is its function?

Answer 15

Branch of facial nerve- connects to the lingual nerve (branch of trigeminal)

Question 16

Why is the innervation of the Chorda Tympani significant?

Answer 16

Gives taste to anterior 2/3rds of tongue.

Parasympathetics

Question 17

Other functions of facial nerve? (3)

Answer 17

1. Supplies muscle of facial expression
2. Supplies sublingual salivary gland
3. Parasympathetics supply submandibular salivary gland

Question 18

Which parts of the upper and lower oral cavity are sensitive to touch? Which nerve innervate them?

Answer 18

1. Superior half- Gingiva, hard palate. CN V2

2. Inferior half- Gingiva, floor of mouth. CN V3

Question 19

Which part of the oral cavity is very sensitive to touch?

Answer 19

Posterior wall of oropharynx

Question 20

What is the gag reflex?

Answer 20

Protective reflex that prevents foreign bodies entering the Larynx or pharynx

Question 21

Which CN is the sensory part of the gag reflex carried out by?

Answer 21

CN IX

Question 22

Which CN is the motor part of the gag reflex carried out by?

Answer 22

CN IX,X

Question 23

What is the reflex of the posterior oropharynx to touch?

Answer 23

Constriction of the oropharynx. Body closes it off to contact

Question 24

Using an endoscope can cause these areas to come into contact? How is this dealt with?

Answer 24

Local anaesthesia blocks sensory AP’s of CN V2,V3 CN VII, IX

Question 25

What is CN V2?

Answer 25

Maxilliary division of the trigeminal nerve

Question 26

Course of this division is same as V3 except in which two areas?

Answer 26

1. Base of skull foramen- sphenoid bone Foramen Rotundum 2. Extracranial part- from foramen rotudum to part supplied

Question 27

Which nerve is CN IX?

Answer 27

Glossopharyngeal

Question 28

What is the course of CN IX in terms of: - CNS origin - Intracranial part - Base of skull foramen - Extracranial part?

Answer 28

1. Medulla 2. Jugular Foramen (in posterior cranial fossa) 3. Jugular foramen- junction between temporal and occipital bone 4. Posterior wall of oropharynx Parasympathetic stimulation- parotid

Question 29

Which nerve innervates the muscles (intrinsic/extrinsic) of the tongue?

Answer 29

Hypoglossal (CN XII)

Question 30

What are the 4 extrinsic muscles of the tongue? (glossus)

Answer 30

1. Styloglossus 2. Palatoglossus 3. Hyoglossus 4. Genioglossus

Question 31

Which of the 4 is the only muscle not to be supplied by CN XII?

Answer 31

Palatoglossus

Question 32

What is the course of the hypoglossal nerve?

Answer 32

1. CNS part- medulla 2. Base of skull foramen- occipital bone 3. Extra-cranial part- most muscles of tongue

Question 33

The contraction of the constrictor muscles of the pharynx are sequential. T/F?

Answer 33

True

Question 34

Which CN innervates the Circular muscles of the pharynx?

Answer 34

CN X- Vagus

Question 35

Which CN supplies the longitudinal muscles of the pharynx?

Answer 35

CN X, XI

Question 36

Which muscle and which CN closes the lips to prevent drooling?

Answer 36

Orbicularis Oris and CN VII

Question 37

Which CN causes the tongue to push the bolus down posteriorly to the oropharynx?

Answer 37

CN XII- Hypoglossal

Question 38

Which CN causes the constrictor muscles of the pharynx to contract to push bolus down to oesophagus?

Answer 38

CN X

Question 39

Which CN innverates the inner longitudinal muscles to raise the larynx, shorten the pharynx and close the laryngeal inlet preventing aspiration?

Answer 39

CN IX,X

Question 40

What vertebral level does the oesophagus begin?

Answer 40

Vertebral level C6- Circopharyngeus muscle

Question 41

What is the mechanical difference between the two oesophageal sphincters?

Answer 41

1. Upper- anatomical | 2. Lower- physiological

Question 42

Function of oesophageal plexus?

Answer 42

Innervates muscles of the oesophageal wall

Question 43

What are three anatomical points of contact of the oesophagus?

Answer 43

1. Root of neck- posterior to trachea 2. Chest- posterior to heart. in contact with Left Atrium 3. In abdomen- through diaphragm, connects with stomach

Question 44

role of lower oesophageal sphincter?

Answer 44

Prevents reflux

Question 45

What 3 regions does the stomach cover?

Answer 45

1. Left hypochodrium 2. Epigastric 3. Umbilical

Question 46

At which point of the stomach does oesophageal emptying take place?

Answer 46

Cardia

Question 47

Structure lying just in front of the pyloric sphincter?

Answer 47

Pyloric Antrum