Upper respiratory tract and skull anatomy

Question 1

Bones of skull

Answer 1

frontal bone- forms forehead

parietal- large lateral and posterior bone

occipital- lateral and posterior bone beneath the parietal

temporal- lateral bones on either side

sphenoid- lateral bones more anterior to temporal

Question 2

What does the face comprise of?

Answer 2

orbit, nose, upper jaw and lower jaw

Question 3

orbit definition

Answer 3

bony protective socket for the eye

Question 4

what forms the orbit?

Answer 4

frontal, sphenoid, maxilla and zygomatic bones

Question 5

what bone forms the nose?

Answer 5

nasal bones form upper part of bridge of nose

Question 6

What joins the maxilla and temporal bone? + what does it form?

Answer 6

zygomatic bone forming the zygomatic arch of the cheek

Question 7

Jaw bones + articulation

Answer 7

upper jaw- maxilla

lower jaw- mandible

temporomandibular joint

Question 8

Nose functions

Answer 8

warms air that passes into the lungs

olfaction- chemoreception, through the sensory olfactory system, that forms the perception of smell

Question 9

Structure of nose

Answer 9

2 nasal bones- superior bridge of nose

2 lateral nasal cartilages

greater alar cartilages, form nostrils

soft tissue

adjacent to margin of maxilla

septum- formed by bony vomer, septal plate of the ethmoid and septal nasal cartilage

superior, middle and inferior meati

superior, middle and inferior conchae

Question 10

what are the meati?

Answer 10

three nasal passages of the nasal cavity, located beneath the conchae

Question 11

what are the conchae? + structure

Answer 11

long, narrow, curled shelf of bone that protrudes into the breathing passage of the nose in humans

act to increase the surface area of the nasal passage

middle and upper conchae are part of the ethmoid bone

inferior conchae formed of different bone

Question 12

what lines the nasal passage + function ?

Answer 12

mucus secreting cells and a rich blood supply that act to warm and add moisture to the air

upper part of nasal cavity lies a specialised sensory epithelium that enables the sensing of odours

Question 13

What blood supply enters the nasal passage?

Answer 13

maxillary artery, facial artery and branches of the ophthalmic artery

originate from both the internal and external carotid supply

Question 14

paranasal air sinuses location + definition

Answer 14

air-filled spaces that are lined with a mucus membrane and have openings into the nasal passage behind the conchae

within the bones surrounding the nasal passage

Question 15

innervation of nose

Answer 15

sensory- trigeminal, 5th cranial nerve

parasympathetic innervation of mucosal glands- pterygopalatine ganglion which is supplied with pre ganglionic fibres from facial 7th cranial nerve

olfactory nerve innervates olfactory epithelium

Question 16

which part of the jaw is moveable?

Answer 16

mandible

Question 17

what muscles move the jaw?

Answer 17

muscles of mastication

Question 18

muscles of mastication + function

Answer 18

temporalis and masseter- jaw closing muscles

medial and lateral pterygoid muscles- protrusion of the lower jaw and sideways movement

Question 19

are all the muscles innervated by the same nerve + nerves

Answer 19

Yes

mandibular part of trigeminal nerve

Question 20

two types of muscles in tongue

Answer 20

intrinsic and extrinsic

Question 21

what are the muscles innervated by?

Answer 21

all innervated by hypoglossal nerve apart from palotoglossus

sensory
anterior 2/3rds from both trigeminal (general sensation) and facial (taste buds)

posterior third- glosssopharyngeal conveys both general and taste sensation

Question 22

what are the muscles innervated by?

Answer 22

all innervated by hypoglossal nerve apart from palotoglossus (innervated by vagus)

sensory
anterior 2/3rds from both trigeminal (general sensation) and facial (taste buds)

posterior third- glosssopharyngeal conveys both general and taste sensation

Question 23

what controls the parotid gland

Answer 23

otic ganglion, which receives parasympathetic pre-ganglionic innervation from the glossopharyngeal nerve

Question 24

other two salivary glands + location and innervation

Answer 24

sub-mandibular and sublingual

lie adjacent to tongue

innervated by post-ganglion nerves from the sub-mandibular ganglion

ganglion innervated from facial nerve

Question 25

explain the mouth

Answer 25

lips- densely innervated structures that act as a sensory surface and a muscular seal to the oral cavity

Question 26

Different parts of the pharynx superior to inferior and markers where they change

Answer 26

nasopharynx

oropharynx

pharyngeal

Question 27

What blocks the pharynx during swallowing?

Answer 27

nasopharynx is blocked off from oropharynx by the elevation of the soft palate

Question 28

Important bone in pharynx + attachments

Answer 28

hyoid

lies in the upper part of neck, above the thyroid cartilage suspended by muscles and the stylohyoid ligament.

Question 29

hyoid function

Answer 29

allows a wider range of tongue pharyngeal and laryngeal movements by bracing these structures alongside each other

Question 30

muscles of pharynx and attachments

Answer 30

muscular tube formed by three constrictor muscles

superior, middle and inferior constrictors

attach to the medial pterygoid plate, hyoid bone, thyroid cartilage and the cricoid cartilage

fused posteriorly as the raphe

Question 31

what innervates the constrictor muscles of the pharynx?

Answer 31

pharyngeal plexus

Question 32

how do the muscles move?

Answer 32

undergo peristaltic contractions in response to stimulation of receptors in the upper part of the oropharynx

Question 33

what is found between the pharynx and oesophagus?

Answer 33

sphincter called the cricopharyngeus

Question 34

structures + function of the larynx

Answer 34

formed of a series of cartilages and membranes which protect the airway and vocal apparatus

epiglottis- leaf like cartilage which covers the opening of the larynx upon swallowing

thyroid cartilage- major anterior cartilage of the larynx- larger in males, Adam’s apple. within this there are two arytenoid cartilages which are the attachment points for the vocal cords and their points of attachment

cricoid cartilage- like a signet ring, lies on top of the trachea

Question 35

vocal cord definition

Answer 35

pair of vibrating membranes responsible for vocalisation

Question 36

How do the vocal cords work?

Answer 36

vocal cords are attached to the arytenoid cartilages- can be separated or brought together by the action of vocal muscles

thyroid cartilage also pivots relative to the cricoid cartilage

muscles pulling the the thyroid closer to the cricoid cartilage act to increase the tension in the vocal cords and hence pitch

muscles running parallel to the vocal cords between the thyroid cartilage and arytenoids slacken the vocal cords, decreasing the pitch

Question 37

Why are men’s voices deeper?

Answer 37

thyroid cartilage is larger

Question 38

What happens during swallowing?

Answer 38

1. teeth breakdown food
2. tongue mixes food with salivary secretions to form a paste like bolus
3. tip of the tongue is elevated against the hard palate and the posterior part of the tongue is depressed, so the bolus moves to the oropharynx
4. sensory receptors on the posterior part of the tongue- glossopharyngeal- initiates a swallowing reflex
5. soft palate is tensed and elevated, sealing the nasal part of the pharynx
6. hyoid bone is elevated as as the bolus passes into the pharynx, where the phayngeal constrictors force the bolus down toward the oesophagus
7. elevation of the hyoid causes the epiglottis to cover the opening of the larynx, protecting the airway
8. the bolus passes over the epiglottis, down into the pharynx and once past the cricophargyngeaus muscle, the hyoid descends and the epigottis flips back to reopen the airway