VOCAB 1
What is the Somatic Nervous System?
Part of the PNS. Consists of motor neurons under your conscious control and produces voluntary muscle action.
What is a photoreceptor?
Also called light receptors. Receptors in the eye that change light into impulses for the brain to understand.
What is a thermoreceptor?
A type of receptor located in the skin that responds to a stimulus. They detect a temperature change.
What is the Optic Nerve?
the nerve that takes impulses from the retina to the brain.
React to sweet, salty, bitter, and sour. (Umami is a meat taste.) Information about taste is sent to the brain and is combined with nose information to create flavor.
What is a reflex?
An involuntary and almost immediate reaction to a stimulus. Reflexes occur when a faster response is necessary.
What are skin receptors?
Receptors in the skin respond to pain, pressure, and vibration. They send messages to the brain and receive another response.
What is the pupil?
An opening in the eye that lets in light. Looks like a black dot, but is actually a small hole.
What is the cochlea?
A coiled, fluid-filled organ that is essential for hearing.
What are papillae?
Small bumps on the tongue, which contain taste buds, contain taste cells.
What is the Parasympathetic Nervous System?
part of the Autonomic Nervous System. Works in a pair with the sympathetic nervous system and decreases heart rate, pupil constriction, and blood vessel constriction.
What are rods?
A type of photoreceptor in the eye that is sensitive to dim light and is important for seeing at night.
What is the cornea?
A clear protective membrane in the front of the eye that lets in light but protects the eye.
What are olfactory cells?
Found in the nasal cavity. Responsible for sensing scents.
What is the Autonomic Nervous System?
Part of the PNS that contains the Sympathetic and parasympathetic nervous Systems. It produces involuntary muscle action and consists of motor neurons not under your conscious control.
What are cones?
A type of thermoreceptor in the eye that are sensitive to bright light and are important for seeing color and fine details.
What is the iris?
A ring of muscle that controls the amount of light that enters the eye. It controls pupil size and gives the eye its color.
What is the retina?
The light-sensitive inner layer of the eye that receives images formed by the lens and transmits them to the optic nerve. Photoreceptors are found in the retina, as they help change light into impulses.
What is the sympathetic nervous system?
Also part of the Autonomic nervous system that works in a pair with the parasympathetic nervous system. Increases heart rate, pupil dilation, and blood vessel dilation.
Describe a feedback mechanism with an example.
A cycle of events in which information in one step controls or affects a previous step. EX: When hot, thermoreceptors send signals to the brain to signal sweat. When cooled down, the brain tells the body to stop sweating through thermoreceptors.
What is the lens?
A clear, oval-shaped piece of material behind the iris that bends and flattens to focus light onto the eye (retina).
What is sound?
Produced by vibrations that create waves. The eardrum sends vibrations to 3 bones. The first bone vibrates against the cochlea, which contains neurons. Neurons convert vibrations and sound waves into electrical impulses for the brain to understand. Impulses travel along the auditory nerve to the brain.