special sense organs (anatomy and physiology) - a brief discussion Pallab Nath
brief discussion on special senses, Basic level class for technicians. topics discussed include eyes and vision, nose and sense of smell, tongue and sense of taste and ears and hearing
This is about the general physiology of sense organs for medical and paramedical professional beginners who choose pharmacy, nursing and physiotherapy to study.
special sense organs (anatomy and physiology) - a brief discussion Pallab Nath
brief discussion on special senses, Basic level class for technicians. topics discussed include eyes and vision, nose and sense of smell, tongue and sense of taste and ears and hearing
This is about the general physiology of sense organs for medical and paramedical professional beginners who choose pharmacy, nursing and physiotherapy to study.
The central nervous system (CNS) is made up of the brain and spinal cord. The brain controls most body functions, including awareness, movements, sensations, thoughts, speech and memory. The spinal cord is connected to the brain at the brain stem and is covered by the vertebrae of the spine.
The outer ear
- pinna
- ear canal
- eardrum
2. The middle ear
- three ossicle bones;
(malleus, incus, stapes)
- two major muscles
(stapedial muscle, tensor
tympani)
- Eustachian tube
3. The inner ear
- cochlea (hearing)
- vestibular system (balance)
4. The central auditory system• PINNA: Important for sound
gathering and localization of
sound
• EAR CANAL or AUDITORY
MEATUS: important for
sound selection
• EARDRUM or TYMPANIC
MEMBRANE:
vibrates in response to
sound/pressure chan
Senses : any of the physical processes by which stimuli are received, transduced, and conducted as impulses to be interpreted in the brain.
The special senses consist of the eyes, ears, nose, throat and skin.
Each of these organs have specialized functions that make if possible for us to experience our environment and to make that experience more pleasant
Introduction to nervous system, Divisions of Nervous System, Nervous System P...Shaista Jabeen
https://www.youtube.com/channel/UCrrAABI7QDRCJ1yMrQCip_w/videos
https://www.facebook.com/ShaistaJabeeen/
https://www.facebook.com/Human-Physiology-Lectures-100702741804409/
Introduction to nervous system, Divisions of Nervous System, Nervous System Physiology
Introduction to nervous system
Divisions of Nervous System
Nervous System Physiology
DIVISIONS OF NERVOUS SYSTEM
CENTRAL NERVOUS SYSTEM
PERIPHERAL NERVOUS SYSTEM
Short Notes
ppt pdf
The ear is the organ of hearing and, in mammals, balance. In mammals, the ear is usually described as having three parts—the outer ear, the middle ear, and the inner ear. The outer ear consists of the pinna and the ear canal.
he sense organs — eyes, ears, tongue, skin, and nose — help to protect the body. The human sense organs contain receptors that relay information through sensory neurons to the appropriate places within the nervous system.
Each sense organ contains different receptors.
General receptors are found throughout the body because they are present in skin, visceral organs (visceral meaning in the abdominal cavity), muscles, and joints.
Special receptors include chemoreceptors (chemical receptors) found in the mouth and nose, photoreceptors (light receptors) found in the eyes, and mechanoreceptors found in the ears.
The central nervous system (CNS) is made up of the brain and spinal cord. The brain controls most body functions, including awareness, movements, sensations, thoughts, speech and memory. The spinal cord is connected to the brain at the brain stem and is covered by the vertebrae of the spine.
The outer ear
- pinna
- ear canal
- eardrum
2. The middle ear
- three ossicle bones;
(malleus, incus, stapes)
- two major muscles
(stapedial muscle, tensor
tympani)
- Eustachian tube
3. The inner ear
- cochlea (hearing)
- vestibular system (balance)
4. The central auditory system• PINNA: Important for sound
gathering and localization of
sound
• EAR CANAL or AUDITORY
MEATUS: important for
sound selection
• EARDRUM or TYMPANIC
MEMBRANE:
vibrates in response to
sound/pressure chan
Senses : any of the physical processes by which stimuli are received, transduced, and conducted as impulses to be interpreted in the brain.
The special senses consist of the eyes, ears, nose, throat and skin.
Each of these organs have specialized functions that make if possible for us to experience our environment and to make that experience more pleasant
Introduction to nervous system, Divisions of Nervous System, Nervous System P...Shaista Jabeen
https://www.youtube.com/channel/UCrrAABI7QDRCJ1yMrQCip_w/videos
https://www.facebook.com/ShaistaJabeeen/
https://www.facebook.com/Human-Physiology-Lectures-100702741804409/
Introduction to nervous system, Divisions of Nervous System, Nervous System Physiology
Introduction to nervous system
Divisions of Nervous System
Nervous System Physiology
DIVISIONS OF NERVOUS SYSTEM
CENTRAL NERVOUS SYSTEM
PERIPHERAL NERVOUS SYSTEM
Short Notes
ppt pdf
The ear is the organ of hearing and, in mammals, balance. In mammals, the ear is usually described as having three parts—the outer ear, the middle ear, and the inner ear. The outer ear consists of the pinna and the ear canal.
he sense organs — eyes, ears, tongue, skin, and nose — help to protect the body. The human sense organs contain receptors that relay information through sensory neurons to the appropriate places within the nervous system.
Each sense organ contains different receptors.
General receptors are found throughout the body because they are present in skin, visceral organs (visceral meaning in the abdominal cavity), muscles, and joints.
Special receptors include chemoreceptors (chemical receptors) found in the mouth and nose, photoreceptors (light receptors) found in the eyes, and mechanoreceptors found in the ears.
In anatomy, special senses are the senses that have organs specifically devoted to them such as vision, gustation, olfaction, audition, and equilibrioception. These senses have specialized organs that detect and process stimuli and send signals to the brain which lead to the perception of that stimulus.
A short simplified anatomy of eye. it includes explanation of all 3 layers of eyes, sclera, choroid and retina. Anatomy of cornea, conjunctiva, pupil, lens, iris, ciliary body etc. physiology of vision, its process and photochemical activity of eyes are discussed in detail.
THIS POWER POINT PRESENTATION IS TO GIVE READERS AN OVERVIEW ON THE ANATOMY AND PHYSIOLOGY OF THE EYE: STRUCTURES, FUNCTIONS OF EACH PART OF THE EYE, AS WELL AS THE PHYSIOLOGY ON HOW THE IMAGE IS CAPTURED IN THE EYE AND TRANSLATED BY THE BRAIN IN ORDER TO HAVE THE MEANINGFUL VIEW OF THE IMAGE.
1 GNM anatomy Unit - 12 - sense organs.pptxthiru murugan
By: M. Thiru murugan
Unit – 12:
Skin, eye, ear, nose and tongue
Physiology of vision, hearing, smell, touch, taste and equilibrium.
Sensory organs or Special senses:
The nervous system must receive and process information about the world outside in order to react, communicate, and keep the body healthy and safe.
Skin, eye, ear, nose & tongue (taste buds) are called sensory organ or special senses.
Sensory organs have special receptors that allow us to smell, taste, see, hear, touch and maintain equilibrium or balance.
Information conveyed from these receptors to the central nervous system is used to help maintain homeostasis(self-regulating process by which biological systems help to maintain stability while adjusting to conditions that are optimal for survival).
Skin:
Skin is the largest organ of our body.
It is related to the sense of touch. The sense of touch is also referred to as tactioception.
The skin contains general receptors which can detect touch, pain, pressure & temperature.
They are present throughout the skin.
Skin receptors generate an impulse, and when activated, is carried to the spinal cord and then to the brain.
Structure of the skin:
The skin is composed of 3 major layers of tissue:
Epidermis layer
Dermis layer
Subcutaneous layer.
The epidermis, the outermost layer of skin, provides a waterproof barrier and creates our skin tone.
The dermis - the middle layer, under the epidermis, contains tough connective tissue, hair follicles, and sweat glands.
The subcutaneous tissue (hypodermis) - deeper/ innermost layer, it is made of fat and connective tissue.
Epidermis:
The epidermis is the thin, outer layer of the skin that is visible to the eye.
Contains different types of cells: keratinocytes, melanocytes, Merkel cells and Langerhans cells.
The skin’s color is created by special cells called melanocytes, which produce the pigment melanin. Melanocytes are located in the epidermis. These form a pigment shield against UV radiation.
It does not contain blood vessels
The epidermis consists of 4 layers: Stratum germinativum, Stratum spinosum, Stratum granulosum, Stratum corneum
Main functions: protection, absorption of nutrients and homeostasis.
Dermis:
The dermis is the middle layer of the skin that offers elasticity.
It is composed of connective tissues and collagen fibers.
is much thicker than the epidermis
The dermis provides a site for the hair follicles, sweat glands, sebaceous glands, blood vessels, lymph vessels, sensory receptors, nerve fibers, muscle fibers & specialized cells (mast cells and fibroblasts).
The main functions of the dermis are:
Protection
Cushioning the deeper structures from mechanical injury;
Providing nourishment to the epidermis;
Playing an important role in wound healing
Subcutaneous:
The subcutaneous is the layer of tissue directly underneath the dermis.
It is also called hypodermis.
This layer of tissue is composed of fat cells and connective tissue.
It is the thickest l
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
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A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
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2. Sensory Systems
• Somatic sensory
• General – transmit impulses from skin, skeletal muscles,
and joints
• Special senses - hearing, balance, vision
• Visceral sensory
• Transmit impulses from visceral organs
• Special senses - olfaction (smell), gustation (taste)
3. • Stimulus - energy source
• Internal
• External
• Receptors
• Sense organs - structures specialized to respond to
stimuli
• Transducers - stimulus energy converted into
action potentials
• Conduction
• Afferent pathway
• Nerve impulses to the CNS
• Translation
• CNS integration and information processing
• Sensation and perception – your reality
Properties of Sensory Systems
4. Sensory Pathways
• Stimulus as physical energy sensory receptor acts as a transducer
• Stimulus > threshold action potential to CNS
• Integration in CNS cerebral cortex or acted on subconsciously
5. Classification by Function (Stimuli)
• Mechanoreceptors – respond to touch, pressure, vibration, stretch, and itch
• Thermoreceptors – sensitive to changes in temperature
• Photoreceptors – respond to light energy (e.g., retina)
• Chemoreceptors – respond to chemicals (e.g., smell, taste, changes in
blood chemistry)
• Nociceptors – sensitive to pain-causing stimuli
• Osmoreceptors – detect changes in concentration of solutes, osmotic
activity
• Baroreceptors – detect changes in fluid pressure
6. Classification by Location
• Exteroceptors – sensitive to stimuli arising from outside the body
• Located at or near body surfaces
• Include receptors for touch, pressure, pain, and temperature
• Interoceptors – (visceroceptors) receive stimuli from internal viscera
• Monitor a variety of stimuli
• Proprioceptors – monitor degree of stretch
• Located in musculoskeletal organs
8. • General somatic – include touch,
pain, vibration, pressure, temperature
• Proprioceptive – detect stretch in
tendons and muscle provide
information on body position,
orientation and movement of body in
space
Somatic Senses
9. Somatic Receptors
• Divided into two groups
• Free or Unencapsulated nerve endings
• Encapsulated nerve endings - consist of one or more neural
end fibers enclosed in connective tissue
10. Free Nerve Endings
• Abundant in epithelia and underlying connective tissue
• Nociceptors - respond to pain
• Thermoreceptors - respond to temperature
• Two specialized types of free nerve endings
• Merkel discs – lie in the epidermis, slowly adapting receptors for light touch
• Hair follicle receptors – Rapidly adapting receptors that wrap around hair follicles
11. Encapsulated Nerve Endings
• Meissner’s corpuscles
• Spiraling nerve ending surrounded by Schwann cells
• Occur in the dermal papillae of hairless areas of the skin
• Rapidly adapting receptors for discriminative touch
• Pacinian corpuscles
• Single nerve ending surrounded by layers of flattened Schwann cells
• Occur in the hypodermis
• Sensitive to deep pressure – rapidly adapting receptors
• Ruffini’s corpuscles
• Located in the dermis and respond to pressure
• Monitor continuous pressure on the skin – adapt slowly
12. Encapsulated Nerve Endings - Proprioceptors
• Monitor stretch in locomotory organs
• Three types of proprioceptors
• Muscle spindles – monitors the changing length of a muscle, imbedded in the
perimysium between muscle fascicles
• Golgi tendon organs – located near the muscle-tendon junction, monitor tension
within tendons
• Joint kinesthetic receptors - sensory nerve endings within the joint capsules, sense
pressure and position
14. Special Senses
Figure 10-4: Sensory pathways
• Taste, smell, sight,
hearing, and balance
• Localized – confined to
the head region
• Receptors are not free
endings of sensory
neurons but specialized
receptor cells
15. Anatomy of the Eyeball
• Function of the eyeball
• Protect and support the photoreceptors
• Gather, focus, and process light into precise images
• External walls – composed of three tunics (layers)
• Internal cavity – contains fluids (humors)
16. The Fibrous Layer
• Most external layer of the eyeball
• Cornea
• Anterior one-sixth of the fibrous tunic
• Composed of stratified Squamous externally, simple squamous internally
• Refracts (bends) light
• Sclera
• Posterior five-sixths of the tunic
• White, opaque region composed of dense irregular connective tissue Provides
shape and an anchor for eye muscles,
• Scleral venous sinus – allows aqueous humor to drain
17. The Vascular Layer
• Middle layer consists of choroid, ciliary body, and iris
• Iris and Pupil
• Composed of smooth muscle, melanocytes, and blood vessels that forms the colored portion of
the eye.
• Function: It regulates the amount of light entering the eye through the pupil.
• It is attached to the ciliary body.
• Pupil is the opening in center of iris through which light enters the eye
• Ciliary body
• Composed of a ring of muscle called ciliary muscle and ciliary processes which are folds located
at the posterior surface of ciliary bodies
• Suspensory ligaments attach to these processes
• Function: secretes the aqueous humor
• The suspensory ligaments position the lens so that light passing through the pupil passes through
the center of the lens of the eye.
18. The Vascular Layer
• Choroid - vascular layer in the wall of the eye.
• Dark brown (pigmented) membrane with melanocytes that lines most of
the internal surface of the sclera. Has lots of blood vessels
• Lines most of the interior of the sclera.
• Extends from the ciliary body to the lens.
• Corresponds to arachnoid and pia mater
• Functions:
• Delivers oxygen and nutrients to the retina.
• Absorb light rays so that the light rays are not reflected within the eye
19. The Inner Layer (Retina)
• Retina is the innermost layer of the eye lining the posterior cavity
• The retina contains 2 layers:
• Pigmented layer made of a single layer of melanocytes, absorbs light after it
passes through the neural layer
• Neural layer – sheet of nervous tissue, contains three main types of neurons
• Photoreceptor cells
• Bipolar cells
• Ganglion cells
20. Photoreceptors
• Two main types
• Rod cells
• More sensitive to light
• Allow vision in dim light
• In periphery
• Cone cells
• Operate best in bright light
• High-acuity
• Color vision – blue, green, red cones
• Concentrated in fovea
21. Regional Specializations of the Retina
• Ora serrata retinae
• Neural layer ends at the posterior margin of the ciliary body
• Pigmented layer covers ciliary body and posterior surface of the iris
• Macula lutea – contains mostly cones
• Fovea centralis – contains only cones
• Region of highest visual acuity
• Optic disc – blind spot
22. The Lens
• A thick, transparent, biconvex disc
• Held in place by its ciliary zonule
• Lens epithelium – covers anterior surface of the
lens
23. The Eye as an Optical Device
• Structures in the eye bend light rays
• Light rays converge on the retina at a single focal point
• Light bending structures (refractory media)
• The lens, cornea, and humors
• Accommodation – curvature of the lens is adjustable
• Allows for focusing on nearby objects
25. Internal Chambers and Fluids
• Anterior segment
• Divided into anterior and posterior chambers
• Anterior chamber – between the cornea and iris
• Posterior chamber – between the iris and lens
• Filled with aqueous humor
• Renewed continuously
• Formed as a blood filtrate
• Supplies nutrients to the lens and cornea
26. Internal Chambers and Fluids
• The lens and ciliary zonules divide the eye
• Posterior segment (cavity)
• Filled with vitreous humor - clear, jelly-like substance
• Transmits light
• Supports the posterior surface of the lens
• Helps maintain intraocular pressure
27. Accessory Structures of the Eye
• Eyebrows – coarse hairs on
the superciliary arches
• Eyelids (palpebrae)
• Separated by the palpebral
fissure
• Meet at the medial and
lateral angles (canthi)
• Conjunctiva – transparent
mucous membrane
• Palpebral conjunctiva
• Bulbar (ocular) conjunctiva
• Conjunctival sac
• Moistens the eye
Figure 16.5a
28. Accessory Structures of the Eye
• Lacrimal apparatus –
keeps the surface of the
eye moist
• Lacrimal gland –
produces lacrimal fluid
• Lacrimal sac – fluid
empties into nasal
cavity
Figure 16.5b
29. Extrinsic Eye Muscles
Figure 16.6a, b
• Six muscles that control movement of the eye
• Originate in the walls of the orbit
• Insert on outer surface of the eyeball
30. Visual Pathways to the Cerebral Cortex
• Pathway begins at the retina
• Light activates photoreceptors
• Photoreceptors signal bipolar cells
• Bipolar cells signal ganglion cells
• Axons of ganglion cells exit eye as the optic nerve
31. • Optic nerve
• Optic chiasm
• Optic tract
• Thalamus
• Visual cortex
• Other pathways
include the
midbrain and
diencephalon
Vision Integration / Pathway
Figure 10-29b, c: Neural pathways for vision and the papillary reflex
32. The Ear: Hearing and Equilibrium
• The ear – receptor organ for hearing and
equilibrium
• Composed of three main regions
• Outer ear – functions in hearing
• Middle ear – functions in hearing
• Inner ear – functions in both hearing and
equilibrium
33. The Outer (External) Ear
• Auricle (pinna) - helps direct sounds
• External acoustic meatus
• Lined with skin
• Contains hairs, sebaceous glands, and ceruminous glands
• Tympanic membrane
• Forms the boundary between the external and middle ear
34. The Middle Ear
• The tympanic cavity
• A small, air-filled space
• Located within the petrous portion of the temporal bone
• Medial wall is penetrated by
• Oval window
• Round window
• Pharyngotympanic tube (auditory or eustachian tube) - Links the middle ear
and pharynx
35. Figure 16.17
The Middle Ear
• Ear ossicles – smallest
bones in the body
• Malleus – attaches to
the eardrum
• Incus – between the
malleus and stapes
• Stapes – vibrates
against the oval
window
36. The Inner (Internal) Ear
• Inner ear – also called the
labyrinth
• Bony labyrinth – a cavity
consisting of three parts
• Semicircular canals
• Vestibule
• Cochlea
• Bony labyrinth is filled
with perilymph
37. The Membranous Labyrinth
Figure 16.18
• Membranous labyrinth - series of membrane-walled sacs and ducts
• Fit within the bony labyrinth
• Consists of three main parts
• Semicircular ducts
• Utricle and saccule
• Cochlear duct
• Filled with a clear fluid – endolymph
38. The Cochlea
• A spiraling chamber in the bony labyrinth
• Coils around a pillar of bone – the modiolus
• Spiral lamina – a spiral of bone in the modiolus
• The cochlear nerve runs through the core of the modiolus
39. The Cochlea
• The cochlear duct (scala media) – contains receptors for hearing
• Lies between two chambers
• The scala vestibuli
• The scala tympani
• The vestibular membrane – the roof of the cochlear duct
• The basilar membrane – the floor of the cochlear duct
40. The Cochlea
• The cochlear duct (scala media) – contains receptors for
hearing
• Organ of Corti – the receptor epithelium for hearing
• Consists of hair cells (receptor cells)
41. The Role of the Cochlea in Hearing
Figure 16.20
42. Auditory Pathway from the Organ of Corti
• The ascending
auditory pathway
• Transmits
information from
cochlear receptors
to the cerebral
cortex
Figure 16.23
43. The Vestibule
• Utricle and saccule – suspended in perilymph
• Two egg-shaped parts of the membranous labyrinth
• House the macula – a spot of sensory epithelium
• Macula – contains receptor cells
• Monitor the position of the head when the head is still
• Contains columnar supporting cells
• Receptor cells – called hair cells
• Synapse with the vestibular nerve
45. The Semicircular Canals
• Lie posterior and lateral to the vestibule
• Anterior and posterior semicircular canals lie in the vertical plane at
right angles
• Lateral semicircular canal lies in the horizontal plane
46. The Semicircular Canals
• Semicircular duct – snakes through each semicircular canal
• Membranous ampulla – located within bony ampulla
• Houses a structure called a crista ampullaris
• Cristae contain receptor cells of rotational acceleration
• Epithelium contains supporting cells and receptor hair cells
48. The Chemical Senses: Taste and Smell
• Taste – gustation
• Smell – olfaction
• Receptors – classified as chemoreceptors
• Respond to chemicals
49. Taste – Gustation
• Taste receptors
• Occur in taste buds
• Most are found on the surface of the
tongue
• Located within tongue papillae
• Two types of papillae (with taste buds)
• Fungiform papillae
• Circumvallate papillae
50. Taste Buds
• Collection of 50 –100 epithelial cells
• Contain three major cell types (similar
in all special senses)
• Supporting cells
• Gustatory cells
• Basal cells
• Contain long microvilli – extend
through a taste pore
51. Taste Sensation and the Gustatory Pathway
• Four basic qualities of taste
• Sweet, sour, salty, and bitter
• A fifth taste – umami, “deliciousness”
• No structural difference among taste buds
52. Gustatory Pathway from Taste Buds
Figure 16.2
• Taste information reaches the
cerebral cortex
• Primarily through the facial
(VII) and glossopharyngeal
(IX) nerves
• Some taste information
through the vagus nerve (X)
• Sensory neurons synapse in
the medulla
• Located in the solitary
nucleus
53. • Olfactory epithelium with olfactory receptors, supporting cells, basal cells
• Olfactory receptors are modified neurons
• Surfaces are coated with secretions from olfactory glands
• Olfactory reception involves detecting dissolved chemicals as they interact with
odorant binding proteins
Smell (Olfaction)
54. Olfactory Receptors
• Bipolar sensory neurons located within olfactory epithelium
• Dendrite projects into nasal cavity, terminates in cilia
• Axon projects directly up into olfactory bulb of cerebrum
• Olfactory bulb projects to olfactory cortex, hippocampus, and amygdaloid
nuclei
