This document discusses the human senses and their associated receptors and sensory organs. It describes different types of receptors including chemoreceptors, thermoreceptors, photoreceptors, mechanoreceptors, baroreceptors, and nociceptors. It then focuses on the senses of taste, sight, and hearing, outlining the key structures and processes involved in gustation via the tongue, vision via the eye, and audition via the external, middle, and inner ear.
2. RECEPTORS
• -- Structures that detect stimuli. They
monitor both external and internal
environmental conditions. Conduct
information about those stimuli to the
central nervous system.
3. TYPES OF RECEPTORS
• Chemoreceptors- they detect • Mechanoreptors- respond to
chemicals. touch, pressure, vibration, &
stretch.
• Thermoreceptors- respond to
changes in temperature. • Baroreceptors- detect changes
in pressure within body
• Photoreceptors- detect structures.
changes in light intensity,
color, & movement. • Nocieptors- respond to pain
caused by either external or
internal stimuli.
5. • Gustation is our sense of taste. It
permits us to perceive the
characteristics of what we eat and
drink.
• Gustatory cells are taste receptors
housed in specialized sensory organs
termed taste buds on the tongue
surface.
8. CONJUNCTIVA
• Stratified squamous epithelium
• Forms a continuous lining of the
external, anterior surface of the eye
• Contains numerous goblet cells which
lubricates and moistens the eye
9. FIBROUS TUNIC
• External layer of • Mostly formed by
the eye wall. touch sclera
• Composed of
anterior cornea &
posterior sclera.
• contains no blood
vessels
10. VASCULAR TUNIC
• Middle layer of the eye wall.
• also called “uvea” (grape)
• composed of three regions: choroid,
ciliary body, & iris
13. THE [[external]] EAR
• A Skin covered cartilaginous structure
called the auricle or pinna.
• The Auricle is funnel shaped and serves
to protect entry into the ear.
• Directs sounds waves into the bony
tube called the external acoustic
meatus.
15. THE [[middle]] EAR
• Contains an air filled tympanic cavity.
• Includes the the bones from lateral to
medial: Malleus, Incus, & Stapes.
• Responsible for amplifying sound
waves and transmitting them into the
inner ear.
17. THE [[inner]] EAR
• Located within the petrous part of the
temporal bone.
• It includes the: vestibule, the semi
circular canals, & the cochlea.
• Mechanisms for equilibrium are located
within the inner ear.
20. • 1) sound waves are collected and funneled by the auricle of the
external ear.
• 2) the vibrations of the tympanic membrane causes movement by the
auditory ossicles.
• 3) pressure waves originate within the inner ear and travel through
the perilymph in the scala vestibuli.
• 4) high-frequency and upper medium frequency pressure waves in
the scala vestibuli cause the vestibular membrane to vibrate, resulting
in pressure wave formation in the endolymph of the cochlear duct.
• 5) the remaining pressure wave vibrations in the cochlear duct are
transmitted to the perilymph of the scala tympani and they exit the
inner ear at the round window.