click below
click below
Normal Size Small Size show me how
7.01
Organization of the nervous system, the brain, the spinal cords, the autonomic n
Term | Definition |
---|---|
afferent | carrying towards a given point (such as the sensory neurons and nerves that carry impulses towards the CNS) |
arachnoid mater | the middle layer of the meninges |
autonomic nervous system (ANS) | the nervous system division that regulates involuntary activities and controls smooth muscles, cardiac muscles, and glands; aka the visceral nervous system |
axon | the fiber of a neuron that conducts impulses away from the cell body |
brain | the nervous tissue within the cranium consisting of the cerebrum, diencephalon, brainstem, and cerebellum |
brainstem | the part of the brain consisting of the midbrain, pons, and medulla oblongata |
central nervous system (CNS) | the brain and spinal cord |
cerebellum | the posterior portion of the brain that helps coordinate movement and maintain balance and posture |
cerebral cortex | the cerebrum's thin surface layer of gray matter |
cortex | the outer region of an organ |
cerebrum | the large upper portion of the brain divided into 2 hemispheres by the longitudinal fissure |
cerebrospinal fluid (CSF) | the watery fluid that circulates in and around the brain and spinal cord for protection |
cranial nerves | the 12 pairs of nerves that are connected to the brain |
dendrite | the fiber of a neuron that conducts impulses towards the cell body |
diencephalon | the part of the brain that contains the thalamus, hypothalamus, and pituitary gland |
dura mater | the strong, fibrous outermost layer of the meninges |
efferent | carrying away from a given point (such as the motor neurons and nerves that carry impulses away from the CNS) |
ganglion | a collection of neuron cell bodies outside of the CNS |
gray matter | unmyelinated tissue of the nervous system |
gyrus | a raised portion of the surface of the cerebrum |
hypothalamus | the brain region that controls the pituitary gland and maintains homeostasis |
interneuron | any neuron between a sensory and motor neuron in a neural pathway |
medulla oblongata | the brain region that connects to the spinal cord and contains centers for controlling respiration, heart rate, and blood pressure |
meninges | the 3 membranes that cover the brain and spinal cord |
midbrain | the part of the brainstem between the diencephalon and the pons that contains centers for coordination of vision and hearing reflexes |
motor | producing movement; describes efferent neurons |
myelin | a whitish, fatty substance that surrouds some axons in the nervous system |
neuroglia | the support cells of the nervous system; aka glial cells |
neuron | the basic unit of the nervous system; aka nerve cell |
neurotransmitter | a chemical that transmits energy across a synapse |
nerve | a bundle of neron fibers outside of the CNS |
parasympathetic nervous system | the ANS section that reverses the response to stress and restores homeostasis by slowing heart rate and stimulating digestive, urinary, and reproductive responses |
peripheral nervous system (PNS) | the portion of the nervous system outside of the CNS |
pia mater | the innermost layer of the meninges |
pons | a rounded area on the brainstem that contains fibers that connect brain regions |
reflex | a simple, rapid, automatic response to a stimulus |
root | a branch of a spinal nerve that connects with the spinal cord |
sensory | pertaining to the senses or sensation; describes afferent neurons |
somatic nervous system | the region of the nervous system that controls skeletal (voluntary) muscles |
spinal cord | the nervous tissue within the spinal column |
spinal nerves | the 31 pairs of nerves that connect with the spinal cord |
sulcus | a shallow groove on the surface of the cerebrum |
sympathetic nervous system | the region of the ANS that mobilizes a response to stress by increasing heart and respiration rates plus delivering more blood to the skeletal muscles |
synapse | the junction between 2 neurons; also the junction between a motor neuron and a muscle or gland |
thalamus | the region of the brain that receives all sensory impulses (except for smell) and directs them to the proper cerebral cortex portion |
tract | a bundle of neuron fibers within the CNS |
ventricle | a small cavity |
white matter | myelinated tissue of the nervous system |