Chapter 15 Nervous System Flashcards
Brain
Contained within the cranium, the center for coordinating body activities. Comprises the cerebrum, cerebellum, and brainstem. The brainstem contains the pons, medulla oblongata, and the midbrain.
Cerebrum
Largest portion of the brain, divided into left and right hemispheres. The cerebrum controls the skeletal muscles, interprets general senses (temp, pain and touch) and contains centers for sight and hearing. Intellect, memory, and emotional reactions also take place here.
Ventricles
Spaces within the brain contain cerebrospinal fluid. This fluid flows through the subarachnoid space around the brain and spinal cord.
Cerebellum
Located under the posterior portion of the cerebrum. Assists in the coordination of skeletal muscles to maintain balance.
Brainstem
Stemlike portion of the brain that connects with the spinal cord. Contains centers that control respiration and heart rate. Three structures comprise the brainstem: the pons, medulla oblongata and midbrain.
Pons
Literally means bridge. It connects the cerebrum with the cerebellum and brainstem.
Medulla oblongata
Located between the pons and spinal cord. It contains centers that control respiration, heart rate and the muscles in the blood vessel walls, which assist in determining blood pressure.
Midbrain
Most superior portion of the brainstem.
Cerebrospinal fluid
Clear, colorless fluid contained in the ventricles that flows through the subarachnoid space around the brain and spinal cord. It cushions the brain and spinal cord from shock, transports nutrients, and clears metabolic waste.
Spinal cord
Passes through the vertebral canal extending from the medulla oblongata to the level of the second lumbar vertebra. It conducts nerve impulses to and from the brain and initiates reflex action to sensory information without input from the brain.
Meninges
Three layers of membrane that cover the brain and spinal cord
Nerve
Cordlike structure made up of fibers that carries impulses from one part of the body to another. There are 12 pairs of cranial nerves and 31 pairs of spinal nerves.
Ganglion
Group of nerve cell bodies located outside the central nervous system.
Glia
Specialized cells that support and nourish nervous tissue. Some cells assist in the secretion of cerebrospinal fluid and others assist with phagocytosis. They do not conduct impulses.
Neuron
Nerve cell that conducts nerve impulses to carry out the function of the nervous system. Destroyed neurons cannot be replaced.