2. Kharkov National Medical University Department of Histology, cytology and embryology LECTURE for dentistry students

3. SENSORY System CARDIOVASCULAR System

4. SENSORY System Organ of Olfaction (Smell) is located in the nasal mucosa Consists of: 1. Supporting cells 2. Basal cells (renewal) 3. Olfactory cells having cilia and axons forming nerve

6. The Eye. Visual organ ＊ fibrous tunic the wall contains vascular uvea neural retina eyeball contents: lens, vitreous body, aqueous humor

7. Pupil Lens Iris Ciliary Body Optic Nerve Central Fovea Cornea Sclera Retina Uvea

8. I. Fibrous tunic has two main portions sclera: dense regular connective tissue cornea: thicker, 5 layers: outer corneal epithelium Bowman's membrane stroma Membrane of Descemet endothelium

9. Cornea contains free nerve endings permeable, avascular, transparent outer

10. II. Uvea – loose con.t. 3 parts: Choroid is nutritive Ciliary body keeps lens Iris is diaphragm with pupil

11. Pupil Lens Iris Ciliary Body Optic Nerve Central Fovea Cornea Sclera Retina Choroid

12. LIMBUS Iris c onstrictor, dilator muscles regulate pupil Ciliary body muscles relax the lens Anterior chamber Posterior chamber = nutritive fluid Lens Iris Ciliary body

13. Pupil Lens Iris Ciliary Body Vitreous Body Cornea Sclera Retina Choroid Is dioptric fluid

14. III. Retina 10 layers of neurons and their processes chain of 3 neurons: layer of visual cells (rods and cones) – outer nuclear, layer of bipolar cells – inner nuclear, layer of ganglionic cells. pigment cells (outermost) 2 sheaths 9 layers of neurons and processes

15. Pupil Lens Iris Ciliary Body Optic Nerve Ora serrata Cornea Sclera Retina Choroid

16. Sclera Muscles Choroid Retina Vitreous Body

17. Pigment epithelium 10 9 8 7 6 5 4 3 2 1 III II I

18. The way of light waves Through the cornea Anterior chamber Pupil Posterior chamber Lens Vitreous body Through all layers of the retina to rods and cones

19. Sclera Choroid Rods cones Inner nuc. Ganglionic l. Outer nu. Ganglionic layer Inner nuclear layer Outer nuclear layer Vitreous body

20. Cham ber Lens Iris- Ciliary body Optic Nerve (blind m.) Central Fovea (yellow m.) Sclera I. Retina photosensitive apparatus Vitreous body II. Cornea dioptric apparatus III.Iris accommodative apparatus

21. Organ of Hearing and Equilibrium Ear contains: External ear Middle ear Inner ear = labyrinth

22. External Ear

23. Middle Ear

24. Middle Ear. Auditory (Eustachian) tube leads to nasopharynx auditory tube

25. Inner ear = labyrinth is located in the temporal bone contains cochlea (organ of hearing), vestibule and semicircular canals, (organ of equilibrium)

26. Inner Ear Vestibule, semicircular canals, cochlea

27. Inner Ear Bony labyrinth is filled with perilymph Contains: Membranous labyrinth is filled with endolymph

28. Section of the inner ear Cochlea (C), vestibule (V) the semicircular canal (SC). C V SC

29. Cochlea is spiral

30. One section of the cochlea spiral canal V estibular membrane (VM) and basilar membrane (BM) divide canal into scala vestibuli (SV), cochlear duct (CD) and scala tympani (ST). SV VM CD ST BM OC S lig Limbus Sl n m

31. SV CD ST o VM BM

32. Scala vestibuli ends with oval window, scala tympani with round, lead to middle ear cochlear duct M E

33. Cochlear duct CD Three angular, three walls VAS – stria vascularis On the basilar membrane locates Organ of Corti (OC) CD OC Limbus S lig BM SL VAS VM

34. Organ of Corti OC tm IHC OHC The tectorial membrane (tm) covers 3 outer hair cells (OHC) and 1inner hair cell (IHC). At the centre the pillar cells (pc) form tunnel (t). Hair cells are supported by phalangeal cells (phc). sl pc t bsl bm phcphc

35. Organ of Corti CD....

36. tectorial membrane outer hair cells inner h.c. outer phalanger cells inner ph.c. pillar cells o

37. Mechanism of hearing: under sound tympanic membrane vibrates, ossicles push oval window.

38. cochlear duct perilymph moves through helicotrema to round window, calls movement of endolymph of cochlear duct and tectorial membrane which irritates hear cells. Nerve fibers take impulse.

39. G M SV SM SV ST H G At the top of the cochlear canal the scala vestibuli connects with the scala tympani – Helicotrema (H), perilymph moves.

40. Organ of equilibrium is similar to o.Corti, locates in the semicircular canals and vestibule, gives information about the force of gravity, acceleration and position of a head

41. Organ of Taste There are taste buds in the epithelium of the tongue papillae.

42. Taste bud There are 3 types of cells in taste bud: 1. basal are stem cells, 2. elongated supporting cells 3. actual taste cells contain microvilli These cells are contacted by sensory nerves from below. high med fp tb

43. Taste sensations Tip of the tongue - sensitive to sweet and salt Lateral edges - sensitive to sour Posterior portion - sensitive to bitter

44. The Cardiovascular System

45. 3 parts: 1. the heart pumps blood

46. 2. MACROCERCULATION – transport

47. 3. MICROCERCULATION – exchange of metabolites, oxygen

48. Generalized Structure of Blood Vessels intima adventitia

49. Types of vessels, because of hemodinamic conditions ARTERIES: elastic, muscular-elastic, muscular VEINS: muscular, unmuscular CAPILLARIES: 1. continuous, 2. fenestrated, and 3. sinusoidal

50. Elastic Arteries Thick-walled arteries near the heart; the aorta and its major branches –Contain elastin in all three tunics –Withstand large blood pressure

51. Muscular Artery Elastic Artery Muscles Elastic

52. Muscular Arteries and Arterioles Muscular arteries – far from heart, where pressure smaller –Have thick tunica media with more smooth muscle and less elastic tissue Arterioles – smallest arteries; lead to capillaries –Control flow into capillaries, contain circular muscle

53. Arteriole, 1-5 smooth. muscle layers, (no) IEL Arteriole

54. Veins Veins – have lower blood pressure and thinner walls than arteries –Valves which prevent backflow of blood 2 types: Muscular – locate below the heart Unmuscular – above Venule – similar to capillary, but wider

55. Capillaries Capillaries are the smallest blood vessels –Wall one cell thick – endothelium on basal lamina Types: 1.2.3.

56. Capillaries 1. 2. 3.

57. LOCATION Of CAPILLARIES 1. – brain, nerves, muscles 2. – kidney, intestine, endocrine glands 3.– red bone marrow, liver, spleen

59. capillary venule Vein

60. HEART

61. Contains pacemaker cells Purkinje fibers-conduct electrochemical impulses, locate between endocardium and myocardium