Unit 5 Lecture 37 Flashcards
What are general senses?
receptors all over the body EXCEPT in ‘sense’ organs
What are sense organs?
The organs responsible for the sense…. (nose, eyes, ears, tongue)
What are the 4 types of general senses?
- Pain
- Temperature
- Body position, touch, pressure
- Chemical stimuli
What are the receptors associated with the general senses?
- Nociceptors
- Thermoreceptors
- Mechanoreceptors
- Chemoreceptors
What are the two main types of chemoreceptors?
CO2 and O2
What are the two categories of general senses?
Somatic and visceral senses
Define somatic senses
Effect body surface
ex: surface temp, touch, pain, and muscle soreness
Define visceral senses
Effect internal organs
- stomach ache, gut cramps
Define special senses
receptors in sense organs
What are the five types of special senses?
- Smell
- Taste
- Sight
- Balance / Equilibrium
- Sound
Where are the receptors found for the special senses?
Ear, nose, eye and tongue
What is true about all sensations?
No matter what the stimulus is, all senses are read in the CNS as ELECTRICAL signals
How do you tell between the different stimuli?
Receptors respond differently to different stimuli
Define receptive field
The area which one sensory afferent neuron can feel
What is true about stimuli in one receptive field?
No matter where the stimuli comes from, it makes a signal from the same sensory afferent neuron
What happens when the receptive field gets smaller?
Smaller receptive fields INCREASE receptor density
What happens when you increase receptor density?
You can feel where the stimuli is coming from more specifically on your body
ex: Hand vs. arm test
Define sensory transduction
The process by which a cell converts a stimulus (taste, sound etc) into an electrical signal
What is the 1st step of sensory transduction?
Stimuli -> receptor and changes membrane potential
How do stimuli change membrane potentials?
Depolarization or hyperpolarization
Define receptor potential
Transmembrane potential difference made by the stimuli of a sensory receptor during sensory transduction
What is the 2nd step in sensory transduction?
Receptor potential effects how fast an AP is made in a sensory neuron
What is step 3 in sensory transduction?
APs travel to CNS along afferent (sensory) pathways
What is step 4 in sensory transduction?
CNS interprets incoming signals
Explain the interpretation of sensory input
The brain assumes any sensory signals reflect the stimulation by the appropriate stimuli
How are all other characteristics of the stimuli conveyed?
Frequency and pattern of the incoming signals
What is important about special senses vs. general senses?
Special senses are pickier about their stimuli
Name the structure of the olfactory senses
Olfactory bulb neuron, olfactory nerve, Olfactory epithelium, olfactory receptor cells, dendrites, and odorant molecules
What is the 1st step of olfactory transduction?
An odorant molecule (ligand) goes through mucus and binds to an olfactory receptor proteinbreaking off the G protein
Step 2 of olfactory transduction
G proteins use ATP to activate Adenylate cyclase (ADC) into producing cAMP
Step 3 of olfactory transduction
cAMP opens Na+ channels
Step 4 of olfactory transduction
Na+ comes into cell -> depolarization -> triggers action potential
Name the main components of gustation
Epiglottis, palatine tonsil, lingual tonsil, vallate papilla, fungiform papila, filiform papilla, and foliate papilla
What is cool about taste buds?
Every taste bud has cells for each sense of taste (sweet, sour, etc)
How does gustation work?
A specific molecule (ie sweet) will bind to the receptor on the matching (sweet) cell -> depolarize -> action potential goes to brain
