Upper digestive tract

Question 1

What are the anatomical boundaries of the mouth?

Answer 1

The mouth is bounded by the lips anteriorly, cheeks laterally, palate superiorly, and the floor of the mouth inferiorly.

Question 2

What forms the roof of the mouth?

Answer 2

The hard palate anteriorly and soft palate posteriorly form the roof of the mouth.

Question 3

What muscle forms the side wall of the oral cavity?

Answer 3

The buccinator muscle forms the lateral wall of the oral cavity.

Question 4

Which cranial nerve innervates the buccinator muscle?

Answer 4

The buccinator is innervated by the buccal branch of the facial nerve (CN VII).

Question 5

What type of joint is the temporomandibular joint (TMJ)?

Answer 5

The TMJ is a synovial joint of the hinge and gliding type.

Question 6

Which bones form the TMJ?

Answer 6

The TMJ is formed by the articulation of the condylar process of the mandible with the mandibular fossa of the temporal bone.

Question 7

What are the four muscles of mastication?

Answer 7

Masseter, temporalis, medial pterygoid, and lateral pterygoid.

Question 8

What is the action of the masseter muscle?

Answer 8

Elevates the mandible to close the jaw.

Question 9

What is the action of the temporalis muscle?

Answer 9

Elevates and retracts the mandible.

Question 10

What is the function of the medial pterygoid muscle?

Answer 10

Elevates the mandible and contributes to side-to-side grinding motion.

Question 11

What is the role of the lateral pterygoid muscle?

Answer 11

Depresses and protrudes the mandible; assists in opening the jaw.

Question 12

Which nerve supplies all muscles of mastication?

Answer 12

The mandibular branch (V3) of the trigeminal nerve (CN V).

Question 13

What are the two sensory branches of the trigeminal nerve to the jaws?

Answer 13

Maxillary nerve (V2) for the upper jaw; mandibular nerve (V3) for the lower jaw.

Question 14

Through which foramen does the mandibular nerve (V3) enter the mandible?

Answer 14

Through the mandibular foramen.

Question 15

What is the significance of the mandibular foramen?

Answer 15

It is the entry point for the inferior alveolar nerve (a branch of V3) into the mandibular canal.

Question 16

What does the inferior alveolar nerve innervate?

Answer 16

The lower teeth and, via its mental branch, the skin of the chin and lower lip.

Question 17

Where does the parotid duct open into the oral cavity?

Answer 17

Opposite the second upper molar tooth.

Question 18

Which salivary gland is located anterior and inferior to the ear?

Answer 18

The parotid gland.

Question 19

What is the innervation of the parotid gland?

Answer 19

Parasympathetic fibers from the glossopharyngeal nerve (CN IX) via the otic ganglion.

Question 20

Where are the sublingual salivary glands located?

Answer 20

In the floor of the mouth, beneath the mucosa, lateral to the submandibular ducts.

Question 21

What structures form the external boundary of the oral cavity?

Answer 21

The lips form the anterior external boundary of the oral cavity.

Question 22

What type of tissue lines the inner surface of the lips?

Answer 22

Stratified squamous epithelium.

Question 23

What muscle is primarily responsible for lip movement?

Answer 23

The orbicularis oris muscle.

Question 24

Which nerve innervates the orbicularis oris?

Answer 24

The facial nerve (cranial nerve VII).

Question 25

What is the function of the orbicularis oris?

Answer 25

Closes and puckers the lips, important in speech and eating.

Question 26

How many types of teeth are there in each half of an adult jaw?

Answer 26

Four: 2 incisors, 1 canine, 2 premolars, 3 molars.

Question 27

What is the total number of permanent teeth in an adult?

Answer 27

32 teeth.

Question 28

What are the functions of the different types of teeth?

Answer 28

Incisors cut, canines tear, premolars and molars grind food.

Question 29

What tissue covers the crown of a tooth?

Answer 29

Enamel.

Question 30

What lies beneath the enamel and forms the bulk of a tooth?

Answer 30

Dentine.

Question 31

What is the innermost part of the tooth that contains nerves and blood vessels?

Answer 31

The pulp cavity.

Question 32

Which ligament anchors the tooth into its bony socket?

Answer 32

The periodontal ligament.

Question 33

What bones form the upper and lower jaws?

Answer 33

The maxilla forms the upper jaw, and the mandible forms the lower jaw.

Question 34

Which bone is movable: the maxilla or mandible?

Answer 34

The mandible is movable.

Question 35

What is the only freely movable joint in the skull?

Answer 35

The temporomandibular joint (TMJ).

Question 36

Which structure passes through the mandibular foramen?

Answer 36

The inferior alveolar nerve and vessels.

Question 37

Which bony landmark is found anterior to the mandibular foramen?

Answer 37

The lingula.

Question 38

What is the mental foramen?

Answer 38

An opening on the anterior mandible where the mental nerve emerges.

Question 39

What does the mental nerve innervate?

Answer 39

The skin of the chin and lower lip.

Question 40

What type of joint movement does the TMJ allow?

Answer 40

Hinge (elevation and depression) and gliding (protrusion and retraction).

Question 41

What is the name of cranial nerve V?

Answer 41

The trigeminal nerve.

Question 42

What are the three branches of the trigeminal nerve?

Answer 42

Ophthalmic (V1), Maxillary (V2), and Mandibular (V3).

Question 43

Is the maxillary nerve (V2) sensory, motor, or both?

Answer 43

Sensory only.

Question 44

What areas does the maxillary nerve (V2) supply?

Answer 44

Upper jaw, maxillary sinus, skin of midface, upper teeth.

Question 45

Through which foramen does V2 exit the skull?

Answer 45

The foramen rotundum.

Question 46

Is the mandibular nerve (V3) sensory, motor, or both?

Answer 46

Both sensory and motor.

Question 47

Through which foramen does V3 exit the skull?

Answer 47

The foramen ovale.

Question 48

Which muscles are innervated by V3?

Answer 48

The muscles of mastication, mylohyoid, anterior belly of digastric, tensor tympani, and tensor veli palatini.

Question 49

Which branch of V3 supplies sensation to the lower teeth?

Answer 49

The inferior alveolar nerve.

Question 50

What is the lingual nerve and what does it do?

Answer 50

A branch of V3 that provides general sensation to the anterior two-thirds of the tongue.

Question 51

What is the chorda tympani and its function?

Answer 51

A branch of CN VII that joins the lingual nerve to provide taste and parasympathetic innervation.

Question 52

Which nerve provides motor innervation for mastication?

Answer 52

The mandibular nerve (V3) of the trigeminal nerve.

Question 53

What type of cartilage is found in the TMJ?

Answer 53

Fibrocartilage (not hyaline, unlike most synovial joints).

Question 54

What structure divides the TMJ into two compartments?

Answer 54

An articular disc.

Question 55

What movements occur in the upper compartment of the TMJ?

Answer 55

Gliding movements (protrusion and retraction).

Question 56

What movements occur in the lower compartment of the TMJ?

Answer 56

Hinge movements (elevation and depression).

Question 57

Which muscle helps protrude the jaw and opens the mouth?

Answer 57

Lateral pterygoid.

Question 58

What role does the temporalis muscle play in the TMJ?

Answer 58

Retracts the mandible and elevates the jaw.

Question 59

Which muscle inserts into the angle of the mandible?

Answer 59

Masseter.

Question 60

What does the TMJ allow that is unique among skull joints?

Answer 60

Side-to-side grinding movement and translation of the jaw.

Question 61

What are the two major parts of the tongue?

Answer 61

The oral part (anterior two-thirds) and the pharyngeal part (posterior one-third).

Question 62

What type of epithelium covers the upper surface of the tongue?

Answer 62

Stratified squamous epithelium (keratinised on anterior dorsum).

Question 63

What are the intrinsic muscles of the tongue responsible for?

Answer 63

Changing the shape of the tongue (e.g. curling, flattening).

Question 64

What are the extrinsic muscles of the tongue responsible for?

Answer 64

Moving the tongue in different directions.

Question 65

Name the four intrinsic muscles of the tongue.

Answer 65

Superior longitudinal, inferior longitudinal, transverse, vertical.

Question 66

Name the four extrinsic muscles of the tongue.

Answer 66

Genioglossus, hyoglossus, styloglossus, palatoglossus.

Question 67

Which nerve innervates all intrinsic and most extrinsic tongue muscles?

Answer 67

The hypoglossal nerve (CN XII), except palatoglossus (CN X).

Question 68

What is the function of the genioglossus muscle?

Answer 68

Protrudes the tongue and depresses the central part.

Question 69

What is the function of the styloglossus muscle?

Answer 69

Elevates and retracts the tongue.

Question 70

What is the function of the hyoglossus muscle?

Answer 70

Depresses and retracts the tongue.

Question 71

What is the function of palatoglossus?

Answer 71

Elevates the posterior tongue and closes oropharyngeal isthmus (CN X innervation).

Question 72

What nerve supplies general sensation to the anterior two-thirds of the tongue?

Answer 72

The lingual nerve (branch of V3).

Question 73

What nerve supplies taste to the anterior two-thirds of the tongue?

Answer 73

Chorda tympani (branch of CN VII).

Question 74

What supplies general and taste sensation to the posterior one-third of the tongue?

Answer 74

The glossopharyngeal nerve (CN IX).

Question 75

What nerve supplies taste buds around the epiglottis?

Answer 75

The vagus nerve (CN X).

Question 76

What is the foramen cecum of the tongue?

Answer 76

A small pit at the junction of the oral and pharyngeal parts, marking embryological origin of the thyroid gland.

Question 77

What are the papillae on the tongue that contain taste buds?

Answer 77

Fungiform, foliate, and circumvallate papillae.

Question 78

Which papillae do not contain taste buds?

Answer 78

Filiform papillae.

Question 79

What is the lingual frenulum?

Answer 79

A midline mucosal fold anchoring the tongue to the floor of the mouth.

Question 80

What is ankyloglossia?

Answer 80

A condition in which the lingual frenulum is unusually short, restricting tongue movement (“tongue-tie”).

Question 81

What are the three pairs of major salivary glands?

Answer 81

Parotid, submandibular, and sublingual.

Question 82

What type of secretion is produced by the parotid gland?

Answer 82

Serous (watery, enzyme-rich saliva).

Question 83

What type of secretion is produced by the submandibular gland?

Answer 83

Mixed (both serous and mucous, mostly serous).

Question 84

What type of secretion is produced by the sublingual gland?

Answer 84

Mainly mucous.

Question 85

What nerve provides parasympathetic innervation to the submandibular and sublingual glands?

Answer 85

The facial nerve (CN VII) via the chorda tympani and submandibular ganglion.

Question 86

Where does the parotid duct open into the oral cavity?

Answer 86

Opposite the second upper molar tooth, via Stensen’s duct.

Question 87

Where do the submandibular ducts open?

Answer 87

At the base of the tongue, on either side of the lingual frenulum (Wharton’s ducts).

Question 88

Where do the sublingual ducts open?

Answer 88

Through multiple small ducts (ducts of Rivinus) along the sublingual fold.

Question 89

What is the most common viral infection of the parotid gland?

Answer 89

Mumps.

Question 90

What is sialolithiasis?

Answer 90

Salivary gland stone, most commonly in the submandibular duct.

Question 91

What cranial nerve passes through the parotid gland?

Answer 91

The facial nerve (CN VII), though it does not innervate it.

Question 92

What is Frey’s syndrome?

Answer 92

Gustatory sweating due to aberrant regeneration of auriculotemporal nerve after parotid surgery.

Question 93

What nerve supplies the auriculotemporal region?

Answer 93

Auriculotemporal nerve (branch of V3).

Question 94

Which salivary gland is most prone to neoplasms?

Answer 94

The parotid gland.

Question 95

What is the clinical relevance of the mental foramen?

Answer 95

Landmark for local anaesthesia in dental procedures for the lower jaw.

Question 96

What does the temporalis muscle attach to on the mandible?

Answer 96

The coronoid process.

Question 97

What is trismus?

Answer 97

Inability to open the mouth fully, often due to spasm of the masseter (e.g., in tetanus or dental infection).

Question 98

What are the two phases of mastication?

Answer 98

Voluntary (initiated by the cortex) and reflex (involving brainstem pattern generators).

Question 99

What sensory receptor helps coordinate jaw pressure during chewing?

Answer 99

Periodontal mechanoreceptors in the ligament.

Question 100

How does the upper GI tract begin functionally and anatomically?

Answer 100

It begins with the mouth, where mechanical digestion by teeth and chemical digestion by salivary enzymes (like amylase) start the digestive process.