The Nervous System (Sensory Reception) Flashcards
Sensation occurs when Neural Impulses generated by the stimulation of sensory receptors arrive at the ________ ______
Cerebral Cortex
When a ray of sunlight hits your skin, sensory _________ send a message to the brain, which receives and processes this information, causing you to feel warmth
sensory
Sometimes the brain can filter out redundant sensory information to prevent over-stimulation. This is known as _______ __________
Sensory Adaptation
What are the four general categories of Sensory Receptors
- Photoreceptors
- Chemoreceptors
- Mechanoreceptors
- Thermoreceptors
What kind of Sensory Receptor is this?
- Stimulated by light (e.g eye receptors)
Photoreceptors
What kind of Sensory Receptor is this?
- Stimulated by chemicals (e.g. nose or tongue receptors)
Chemoreceptors
What kind of Sensory Receptor is this?
- Stimulated by pressure (e.g. ear receptors)
Mechanoreceptors
What kind of Sensory Receptor is this?
- Stimulated by heat/cold (e.g. skin receptors)
Thermoreceptors
Vision is associated with the stimulation of ______________ at the back of the eye by light energy
Photoreceptors
Rods and Cones in the ______ convert this light energy into electrochemical impulses which the brain uses to form an image
Retina
Are Rods concentrated on the side of the Retina or the Center?
SIDE
Are Cones concentrated on the side of the Retina or the Center?
CENTER
What are the three layers the eye?
- Sclera
- Choroid
- Retina
The tough outer layer of the eye
Sclera
front of the Sclera
- Protective layer (transparent)
Cornea
Light enters the eye and is bent (refracted) through the ______
Cornea
unequal curvature of the Cornea
Astigmatism
Which layer of the eye is this?
- Middle layer
- Contains blood vessels to nourish the eye
- Dark in colour to absorb light
Choroid
Muscle attached to the lens for focusing
Ciliary
Pigmented muscle
- controls the amount of light entering the eye
Iris
Inner layer of the eye
Retina
Forms optic nerve that exits back of the eye (Blind Spot)
Ganglion layer
What is in the Photoreceptor layer?
Rods and Cones
located on periphery on the eye
- Night vision
RODS
Concentrated near center of the eye
- Fovea Centralis: most acute vision
- Colour Vision
Cones
opening in front of the eye
Pupil
Adaptation is when PUPIL…
dilates or constricts
focuses light on the retina
Lens
Accommodation is when LENS _______ shape if objects are near or far
Changes
The liquid that maintains Cornea Shape
Aqueous Humour
The liquid that maintains Eyeball Shape
Vitreous Humour
Light enters the eye through the CORNEA, past the PUPIL and through the ____ which helps focus light
LENS
The light pasts through the LENS and strikes photoreceptors in the ______
Retina
Photoreceptors relay sensory impulses to the Occipital lobe of the brain via the _____ _____
Optic Nerve
______ (nearsightedness)
- the inability to see objects at a distance
- eyeball is elongated (too long), so focused light falls in front of the retina
Myopia
_________ (farsightedness)
- the inability to see close objects
- eyeball is shortened, so focused light falls behind the retina
Hyperopia
Colourblindness is a genetic condition caused by a lack of specific Cones, or ______ receptors
- Most color blind individuals lack the Cones which respond to red-green wavelengths, so they cannot perceive those colours (see them as shades of brown)
COLOUR
Which part of the ear specializes in HEARING?
Cochlear
Which part of the ear specializes in BALANCE?
Semicircular Canals
Which part of the ear specializes in PRESSURE?
Eustachean Tube
Hearing is associated with fluctuations in air pressure, called…
Sound Waves
_______receptors in the fluid-filled inner ear convert the energy of Sound Waves into Electrochemical Impulses which the brain perceives as sound
Mechanoreceptors
Balance is associated with movement. Mechanoreceptors in the ear convert the energy of liquid movement into what?
Electrochemical Impulses
Sound waves are directed by PINNA to the ________ CANAL, where they strike the TYMPANUM (aka tympanic membrane/ ear drum)
AUDITORY
Sound waves push against the TYMPANUM, and vibrations are passed on and amplified by the three ________ (bones).
OSSICLES
Vibrations are concentrated on the Oval Window, causing changes in ________ within the organs of the inner ear
Pressure
Pressure changes stimulate hair cells found in the ORGAN OF CORTI within the coiled _______
COCHLEA
The stimulated hair cells found in the ORGAN OF CORTI within the coiled COCHLEA generates an action potential in the AUDITORY NERVE that is sent to which lobe of the brain?
Temporal Lobe
Pressure changes cause waves in the fluid of the Semicircular Canals which act to maintain _______
balance
The __________ Tube connects to the throat, allowing air pressure to equalize
Eustachean
The tongue contains _____receptors that allow us to taste substances entering the mouth
CHEMOreceptors
Impulses from taste buds, where Chemoreceptors are located, then travel to the ________ Lobe
Parietal
Each odour particle is thought to fit like a lock&key into specific Chemoreceptors which line the nasal cavity, known as _________ Cells
Olfactory
OLFACTORY CELLS transmit signals to the OLFACTORY ____ in the Brain
BULB
Perception of movement and body position in space (muscles)
Proprioception
