Senses Flashcards
Sensory Receptor
Is able able to convert a signal from the environment, called a stimulus, into a nerve impulse.
Sensory Transduction
The transversion of a stimulus from the environment into a nerve impulse
Exteroceptors
Sensory Receptors that detect stimuli from outside the body such as those that result in taste, smell, vision, hearing, and equilibrium.
Interoceptors
Receive stimuli from inside the body. They are directly involved in homeostasis.
Examples
- Baroreceptors: Respond to changes in blood pressure
Osmoreceptors: Monitor the body´s water and salt balance
Chemoreceptors: Monitor ph of blood
Types of Sensory Receptors
Chemoreceptors- respond to chemical substances in the immediate vicinity
Photoreceptors- respond to light energy
Mechanoreceptors- are stimulated by mechanical forces which most often result in pressure of some sort
Thermoreceptors- stimulated by changes in tempeture
Sensation
The conscious perception of stimuli. If nerve signals finally reach the cerebral cortex, sensation occurs.
Sensory Adaptation
Decrease in response to stimulus over time
Layers of the Eye
3 layers: sclera (outermost), choroid (middle, thin, extensive blood supply, dark pigment absorbs stray light rays that photorecepters have not absorbed), and the retina (filled with clear gelatinous material called the vitreous humor)
Iris
- Iris regulates size of pupil. Behind the iris, the choroid thickens and forms the circular ciliary body.
Pupil
- Pupil is a hole in the center of the iris through which light enters the eye
Aqueous Humor
- Fills the anterior compartment
- Clear, watery fluid
Vitreous Humor
- Holds the retina in place and supports the lense
- Clear gelatinous material
- Contains photoreceptors called rod cells and cone cells
