Module 23: Sensation & Sense Organs Flashcards
Sensory receptors transmit information about
–Type of stimulus
–Location of stimulus
–Intensity of stimulus
What do chemoreceptors react to?
Odors and tastes, and concentration of various chemicals (such as glucose or carbon dioxide) in the body
How are mechanoreceptors reacted?
Respond to factors - such as pressure, stretch, or vibration - that change the position of a receptor
Thermoreceptors are activated by
A change in temperature
What are Nociceptors ?
Pain receptors that respond to tissue damage from trauma as well as from heat, chemicals, pressure, or a lack of oxygen
What are photoreceptors?
Found only in the eyes, these receptors respond to light
What receptor is found in skeletal muscle, joints, and tendons, and provide information about body movement, muscle stretch, and the general orientation of the body
Proprioceptors
Taste (gustation) results when chemicals come in contact with taste buds, most of which are located around protrusions called what?
Papillae
Nociceptors, or pain receptors, Consist of free nerve endings that carry pain impulses to the brain. They fall into one of two categories. What are the two categories and what type of pain do you experience?
Fast pain fibers: Abundant in the skin and mucous membranes, these fibres produce a sharp, localized, stabbing-type pain at the time of injury
Slow pain fibers: These fibres are congregated on deep body organs and structures and produce a dull, aching pain
*What is referred pain?
Pain originating in a deep organ may be sensed as if it’s originating from the body surface – sometimes at a totally different part of the body
*Why does referred pain occur?
Because sensory fibres from an organ and those from an area of skin conversion a single pathway
What are the special senses? (5)
Taste, smell, hearing, vision, equilibrium
Through which cranial nerves do taste buds send impulses to the brain?
The facial nerve, glossopharyngeal nerve, vagus nerve
What is the auricle?
Shaped by cartilage and funnel sound into the auditory canal
What is the auditory canal?
Leads through the temporal bone to the eardrum
*What is the role of the auditory (or eustachian)tube?
Equalizers pressure on both sides of the tympanic membrane
Can also allow infection to spread from the throat to middle of the ear
*Where are the structures for hearing found?
Cochlea
*The spirals of the cochlea are divided into three compartments. Describe the compartments
Middle compartment - is a triangular duct (called the cochlear duct) filled with endolymph
The outer two compartments are filled with perilymph
- resting on the floor (basilar membrane) of the triangular duct is the hearing sense organ, which is?
Organ of corti
The utricle and saccule reside inside the:
Vestibule
Inside that ear, what is the structure that is crucial for the maintenance of equilibrium and balance?
Semicircular Canals
What part of the inner ear is the structure, which marks the entrance to the labyrinths, contains organs necessary for the sense of balance?
Vestibule
What is the snail-like structure which contains the structures for hearing?
Cochlea
What is the hearing sense organ that rests on the floor (basilar membrane) of the cochlear duct?
Organ of Corti
What is a fraction in the process of vision?
Bending of light rays. Light rays entering the eye must be bent so they focus precisely on the retina
What is convergence in the process of vision?
Convergence lines up the visual axis of each eye toward the object so that light rays fall on the corresponding spots on each retina
What is the function of rods?
Handle vision in a little late but cannot distinguish colours
What is the function of cones?
Function in bright light in a responsible for colour vision and detail
