25-1~25-2 Flashcards
Peripheral nervous system
All parts parts of the nervous system aside from the brain and spinal cord; connects all parts of the body to the central nervous system
Central nervous system
Brain and spinal chord; processes information that comes from the peripheral nervous system
Neuron
A nerve cell that specializes in transferring messages in the form of fast-moving electrical energy called impulses
Cell body
The large region in the center of a neuron
Dendrites
Short, branched extensions of a cell that allows it to recieve impulses from thousands of other cells
Axon
Elongated extensions of neurons with branches that allow information to pass to other cells
Axon terminal
Tip of the axon
Sensory neurons
Neurons that gather information about what is happening in and around your body
Receptors
Specialized nerve endings that detect changes inside and outside the body
Motor neurons
Neurons that send impulses from the brain and spinal cord to other systems
Nerve
A collection of axons bundled together with blood vessels and connective tissue; most have axons of sensory and motor neurons
Somatic nervous system
Consciously controlled movements (voluntary)
Auto nomadic nervous system
Involuntary actions
Brain
A mass of nerve tissue that is the main control center of the nervous system
Three main parts of the brain
Cerebrum, cerebellum, medulla
The largest part of the brain, mushroom cap shape, where most memories are stored, controls voluntary movements, allows you to sense touch, light, sound, odor, pain, heat, and cold, has two halves
Cerebrum
Left hemisphere and right hemisphere
Speaking, reading, writing, solving problems
Spatial thinking, music, emotions
Second largest part of brain, lies beneath back of cerebrum, sensory information like skeletal muscles and joints, keeps track of body position, controls balance
Cerebellum
Connects with spinal chord, 3 cm long, essential to living, controls involuntary processes such as blood pressure, body temperature, heart rate, breathing
Medulla
Reflex
Involuntary and almost immediate in response to stimulus
Feedback mechanism
Chain of responses and events
Cornea
Protects the eye and let’s light enter
Pupil
Opening where light enters
Retina
Layer of light sensitive cells
Photoreceptors
Special neuron that changes light into impulses
Iris
Ring of muscle that controls pupil
Lens
Oval shaped piece of clear curved material behind the iris
Thermoreceptors
Receptor that responds to temperature change
Cochlea
Fluid filled organ in inner ear
Eardrum
Thin outer membrane that seperates outer ear and middle ear
Papillae
Bumps on tongue
Taste cell
Receptors for taste
Olfactory cell
Receptors for smell
