Chapter 17 - The Nervous System Flashcards
Central nervous system
Brain and spinal cord
Peripheral nervous system
All nerves outside of the brain and spinal cord
Neurons
Conducting tissue of the nervous system
Neuroglia
Cells that support and protect the nervous system
Dendrite
Carries impulses toward the cell body
Axon
Carries impulses away from the cell body
Myelin
Whitish, fatty material that insulates and protects the axon and speeds electrical conduction.
Myelinated
Covered axons
Grey matter
Unmyelinated tissue.
Sensory or afferent neuron
Transmits impulses toward the CNS
Motor or efferent neuron
Transmits impulses away from the CNS
Interneurons
Connecting cells of the CNS
Synapse
Point of contact between two neurons. Energy is passed from one cell to another.
Ganglion
Collection of cell bodies along the pathway of a nerve
4 parts of the brain
Cerebrum, diencephalon, brain stem, and cerebellum.
Cerebrum
Largest part of the brain. Largely composed of white matter. Thin outer layer of grey matter called the cerebral cortex
Cerebral cortex
Outer layer of the cerebrum. Higher functions of memory, reason, and abstract thought occur here.
Sulci
Grooves of the grey matter
Gyri
Raised areas of the grey matter
Diencephalon
Contains the thalamus, hypothalamus, and pituitary gland.
Parts of the brainstem
Midbrain, pons, medulla oblongota
Midbrain
Reflex centers for improved vision and hearing
Pons
Bulge on the anterior surface of the brainstem. Fibers that connect the brains different regions.
Medulla oblongota
Connects the brain to the spinal cord. Vital center that controls heart rate, respiration, and blood pressure.
Cerebellum
Divided into two hemispheres. Controls voluntary muscle movement and maintains posture, balance, and coordination.
Ventricles
4 of them that produce cerebral spinal fluid that acts a protective cushion.
Meninges
3 protective layers that protect the brain and spinal cord
Dura mater
Hard outermost layer of the meninge
Arachnoid mater
Thin web like middle layer of the meninge
Pia mater
Thin, vascular innermost layer attached directly to the brain and spinal cord.
Cranial nerves.
12 of them identified by Roman numerals.
Olfactory
I. Carries impulses for the sense of smell