nervous system

• Central Nervous System (CNS) is the body’s primary information processing center
• Nerve is a bundle of neuron fibers surrounded by connective tissue
• Peripheral Nervous System (PNS) consists of all the nervous tissue outside the CNS
• Stimulus is information about an environmental change
• Sensory neurons carry information about stimuli to the CNS
• Sensory receptors are highly specialized cells that receive stimuli
• Interneurons are neurons located entirely within the CNS
• Motor Neurons carry signals like muscles contracting and hormones being secreted away from the CNS
• Reflex is a rapid, automatic response
• Dendrite receives signals and carries them toward the neuron's cell body
• Axon carries electrical impulses away from the cell body and toward other cells
• Myelin Sheath is an insulated material that surrounds the axons
• Nodes are the uninsulated part of the axon fiber where the signal can jump between
• Depolarization is a voltage change across a membrane
• Threshold is a certain level the membrane must be depolarized to
• Action potential is a strong depolarization which is the start of the nerve signal
• Synapse is the junction between knobs on the neuron and another cell
• Synaptic cleft is the tiny space between which the nerve signal must be transmitted
• Neurotransmitters are small, nitrogen-containing organic compounds
• Somatic Nervous System is part of the peripheral nervous system associated with skeletal muscle voluntary control of body movements
• Autonomic Nervous System is responsible for control of bodily functions not consciously directed, such as breathing, heartbeat, and digestive processes
• Sympathetic Division mobilizes the body’s nervous system fight-or-flight response
• Parasympathetic Division calms the body and returns it to regular maintenance function
• Meninges are connective tissue that cushions the brain and spinal cord
• Cerebrospinal fluid bathes the brain and spinal cord, acts as a shock absorber, and allows for the exchange of nutrients
• Cerebrum is the largest and most complex part of the brain
• Corpus Callosum connects the hemispheres of the brain and supports communication
• Cerebral cortex is the outer region of the cerebrum
• Cerebellum is the coordination center for body movements
• Brainstem is the lower section of the brain that includes the medulla oblongata, the pons, and the midbrain
• Thalamus is located in the middle of the brain, sorts information going to and coming from the cerebral cortex
• Hypothalamus helps to regulate body temperature, blood pressure, hunger, thirst, and emotions