Sense Organs

Sensory Receptors

• nerve endings and cells that detect sensory information

Sensation

• occurs when the neural impulses arrive at the cerebral cortex

Perception

• How cerebral cortex interprets the meaning of the sensory information

Photoreceptors

• light energy stimulates these receptors located in retina of eye

• -stimulus converts EMR → chemical change → nerve impulse

Chemoreceptors

• receptors located on tongue and within the nose

• a stimulus must be a substance mixed with solvent (H20)

• stimulus attached to receptors

• receptors produce a nerve impulse

Mechanoreceptors

• Receptors located within the inner ear and skin

• pressure causes a physical movement of receptor

• produces a nerve impulse

Proprioceptors

• receptors located near or within muscle tissue

• movement produces a neural impulse

Conversion

• all sensory receptors convert on energy form (info) about the external environment into electrochemical energy (nerve impulses)

Stimulus

• each individual receptor is capable of responding to only one kind of stimulsu

Sensation

• stimulation of grouped receptors results in only one type of sensation

Threshold

• grouping of sensors ensures stimulus reaches threshold levels