chapter 38 pp Flashcards
Perceptions
Any sensory stimuli of which humans, and perhaps other animals, become conscious
Sensory receptors
Specialized cells capable of detecting changes in internal or external conditions, and of communicating that information to the central nervous system
Capable of facilitating sensory transduction (Conversion of an event (stimulus) occurring in the environment into a nerve impulse)
There is no difference between the nerve impulses carried by different types of sensory nerves.
Interoceptors
receive stimuli from inside the body.
exteroceptors
allow an animal to detect information in its environment
Chemoreceptors
Sensory receptors responsible for taste and smell
Photoreceptors
Sensory receptors responsible for responding to light
Mechanoreceptors
Sensory receptors stimulated by mechanical forces, such as pressure
Electromagnetic receptors
Respond to heat or light energy
Thermoreceptors
Sensory receptors stimulated by changes in temperature
Chemoreception
is found almost universally in all animals.
Thought to be the most primitive sense
Allows organisms to locate food, find a mate, detect dangerous environmental chemicals
Housefly chemoreceptors
are on their feet.
Can also detect airborne pheromones
Chemical messages passed between individuals
Snakes’ Jacobson’s organs
are in the roof of their mouths.
Send sensory information to the brain
taste buds
are located primarily on the tongue.
Taste buds open at a taste pore.
Taste buds have supporting cells and elongated taste cells that end in microvilli.
Five primary tastes
Sweet, sour, salty, bitter, and umami (savory)
Taste buds for each are located throughout the tongue, although certain regions may be more sensitive to particular tastes.
A food may stimulate more than one type of taste bud.
Brain surveys overall pattern of incoming impulses.
olfactory cells
human sense is dependent on this
Located within olfactory epithelium in the roof of the nasal cavity
Each cell ends in a tuft of cilia with receptor proteins for odor molecules.
Each cell has 1 out of 1,000 different types of receptor proteins