the nasal cavity is innervated mainly by the mandibular and
maxillary divisions of the trigeminal nerve [see diagram]. the anterior ethmoidal nerve branches off of V1 and enters the nasal cavity via the anterior ethmoidal foramen and innervates the anterior ethmoidal sinus, the anterior nasal cavity, and the frontal sinus. V1 also has an external branch that innervates the external nose. V2 comes through the foramen rotundum into the pterygopalatine fossa, and from there into the nasal cavity by way of the sphenopalatine foramina. at this point V2 has three branches that innervate the nasal cavity: 1) greater and lesser palatine branches travel through the palatine foramina and innervate the inferior palate. 2) posterior lateral nasal nerves innervate the concha. 3) nasopalatine branches go through the incisive canal and innervate the inferior aspect of the hard palate. V2 also has an external branch that innervates the exterior of the nasal cavity-- the infraorbital branch innervates the cheek and infraorbital canal and foramina, and the superior alveolar nerve innervates the top row of teeth.the two major arteries in the nasal cavity are the sphenopalatine and the anterior/posterior ethmoidal arteries. the anterior/posterior ethmoidal branches off of the opthamalic branch of the internal carotid and the sphenopalatine artery branches off of the maxillary branch of the external carotid. it is due to the extensive anatamoses between the blood vessels in this area that nosebleeds are so difficult to stop.
olfactory receptors are bipolar neurons contained in the upper recesses of the nasal cavity that last 1-2 months before being replaced by undifferentiated basal cells. they have ciliated cells called sensory processes that project into the mucous layer which have receptors for specific "odorant" molecules from the environment, which trigger action potential in these neurons by g-proteins and second messenger cascades.
the last section dealt with the larynx muscles and cartilage. the larynx area is made up largely of the thryoid, arytenoid, and cricoid cartilage and also contains the epiglottis, which is attached to the inner surface of the thyroid cartilage. the quadrangular membrane is the connective tissue sheet from the arytenoid cartilage to the epiglottis, while the "conus elasticus" is the connective tissue sheet from the arytenoid/cricoid cartilage to the thyroid cartilage, the upper free edges of which forms the vocal cords.
there are several sets of muscles that control different types of movement in the larynx. the aryepiglottic, thryoepiglottic, and oblique arytenoid muscles close the laryngeal inlet. the posterior cricoarytenoid and lateral cricoarytenoid open the glottis (the space between the vocal cords) while the transverse and oblique arytenoid close it. finally, the cricothryoid lengthens the vocal cords (producing lower pitches) and the thyroarytenoid and vocalis shortens (higher pitches).
questions
nasal cavity and bones...
1. which bones is the nasal aperture made of?
2. what are the types of cartilages in the nose?
3. what is the fleshy part of the nose called and what is it made of?
4. which bones form the walls and the hard palate?
5. what part of the nasal cavity does the ethmoid form?
6. perpendicular plate of ethmoid forms...
7. what passes through the cribiform plate of the ethmoid bone?
8. besides the ethmoid, what else forms the nasal septum?
concha and meatuses...
9. describe the conchae bones.
10. inferior meatus is the site of...
11. middle meatus is the site of...
12. superior meatus is site of...
13. what is an important function of the conchae?
14. what does the respiratory epithelium do?
sinuses...
15. what are the paranasal sinuses?
16. where does the sphenoid sinus open?
17. where is the frontal sinus and where does it open?
18. where is the maxillary sinus and where does it open into?
19. proximity of sinus to maxillary teeth permits...
20. where does the ethmoid sinus open into?
innervation...
21. which nerves are the nasal cavity and hard palate innervated by?
22. describe the passage of the anterior ethmoidal branch of V1 into the nasal cavity.
23. what does the anterior ethmoidal nerve innervate?
24. what does the anterior ethmoidal nerve branch into?
25. describe the passage of the maxillary branch (V2) into the palatine area and the nasal cavity.
26. what does V2 branch into in the nasal cavity area?
27. where do the posterior lateral nerves project?
28. where do the greater and lesser palatine nerves project?
29. where do the nasopalatine nerves project?
30. what are the external branches of V2 and what do they innervate?
31. what is the hay fever ganglion? what nerves does it receive and what nerves does it project?
32. describe the parasympathetic innervation of the nasal cavity.
arteries...
33. what are two of the major arteries in the nasal cavity?
34. where does the anterior/posterior ethmoidal artery branch off of?
35. where does the sphenopalatine artery branch off of?
36. why are nosebleeds difficult to stop?
olfaction...
37. what are olfactory receptors? where are they?
38. what is the live span of a olfactory receptor? what happens when they die?
39. what are "sensory processes" and what do they do?
40. how do odorants trigger an action potential?
larynx and vocal cords...
41. what is the cartilage associated with the larynx?
42. what are some landmarks of the thyroid cartilage?
43. where is the epiglottis attached?
44. what does the thyrohyoid membrane do?
45. what are the vocal cords made of?
46. what is the conus elasticus?
47. what is the space between vocal cords called?
48. what is the quadrangular membrane?
49. what is the vestibular fold?
50. where is the ventricle of the larynx?
muscles and innervation of larynx...
51. what are the muscles that close the laryngeal inlet?
52. what are the muscles that open and close the vocal cords?
53. what are the muscles that lengthen and shorten vocal cords?
54. why do males have lower pitched voices than females?
55. what nerve innervates the larynx?
56. which branch supplies motor innervation to cricothyroid and sensory innervation to the mucosa?
57. which branch supplies motor innervation to all of the other intrinsic larynx muscles?
answers
1. nasal and maxilla
2. lateral, septal, alar
3. ala nasi, made of loose CT
4. maxilla and palate bones
5. the roof and part of the nasal septum.
6. part of nasal septum.
7. olfactory nerves.
8. vomer, septal cartilage.
9. curved bones covered with mucosa that overlie meatuses.
10. nasolacrimal opening (which is why crying produces a runny nose)
11. site of opening of the maxilla, ethmoid, frontal sinuses.
12. site of opening of the sphenoid sinus.
13. increasing surface area of nasal cavity.
14. warms, humidifies, dehumidifies air.
15. cavities within bones: sphenoid, ethmoid, frontal, maxillary.
16. above the superior concha.
17. within frontal bone, deep to the glabella and superior orbital fissure; opens into the middle meatus.
18. within maxilla bone, empties into middle meatus.
19. intercommunication of infections.
20. lateral nasal cavity.
21. V1 and V2.
22. anterior ethmoidal branch of V1 travels into the nasal cavity via the anterior ethmoidal foramen.
23. the frontal sinus, anterior ethmoidal sinuses, and anterior nasal cavity.
24. the external nasal branch which innervates the external nose.
25. enters the pterygopalatine fossa via the foramen rotundum and the nasal cavity via the sphenopalatine foramen.
26. posterior lateral nerves, greater/lesser palatine nerves, nasopalatine nerves.
27. the conchae
28. through the palatine foramina to the inferior palate.
29. into the anterior aspect of the hard palate via the incisive foramen.
30. the infraorbital branch innervates the cheek and infraorbital canal and foramen. the superior alveolar branches innervate the upper teeth.
31. the pterygopalatine ganglion; receives the facial nerve (CN VII) and projects nerves to the nasal, palatine, and lacrimal glands via V1 and V2.
32. preganglionics from the T1 level project to the superior cervical ganglion. postganglionics follow blood vessels to nasal cavity.
33. sphenopalatine and anterior/posterior ethmoidal.
34. from the opthamalic branch of the internal carotid.
35. from the maxillary branch of the external carotid.
36. because of the extensive anastamoses of arteries in the nasal cavity.
37. bipolar neurons within olfactory epithelium in upper recesses of nasal cavity.
38. 1-2 months, replaced by undifferentiated basal cells
39. ciliated cells that project into the mucus layer which have receptors for specific odorants.
40. via G proteins and second messengers.
41. thyroid, arytenoid, cricoid
42. lamina, thyroid notch. superior/inferior horns. laryngeal prominence (adam's apple).
43. inner surface of thyroid cartilage.
44. suspends larynx from hyoid bone.
45. upper free edges of the conus elasticus.
46. CT sheet from arytenoid/cricoid cartilage to thyroid cartilage.
47. rima glottidis.
48. CT sheet from arytenoid cartilage to epiglottis.
49. lower free edge of quadrangular membrane.
50. cavity between vocal and vestibular folds.
51. aryepiglottic, thyroepiglottic, oblique arytenoid
52. posterior cricoarytenoid, lateral cricoarytenoid open glottis, transverse and oblique arytenoid close glottis.
53. cricothyroid lengthens, thyroarytenoid and vocalis shortens.
54. higher testosterone levels elongate the thyroid cartilages and thus produce longer vocal cords and lower voices.
55. vagus
56. superior laryngeal
57. recurrent laryngeal
No comments:
Post a Comment