Chapter 9 Test Flashcards
Know the difference between the ascending and descending tracts of the spinal cord.
Ascending refers to sensory information being carried TO the brain and descending refers to motor impulses being carried FROM the brain to the muscles and glands.
Schwann cells
produce the myelin sheath that surrounds the axons of peripheral nerves
Ependymal cells
form an epithelial-like membrane that lines the cavities in the brain called ventricles and the central canal in the spinal cord, produce cerebrospinal fluid
Oligodendrocytes
aligned along axons of neurons, produce insulating layers of myelin (myelin sheath)
Microglia
small, “spider-shaped” cells scattered throughout the central nervous system. Develop from white blood cells, they remove bacterial cells and cellular debris and also form scars in areas of damage
General functions of the nervous system
The general functions are sensory input, integration, and processing.
Motor Neurons
Multipolar and conduct impulses out of the brain or spinal cord to effectors. Motor impulses control muscle contraction and the secretions of glands.
Interneurons
Lie entirely within the brain or spinal cord. They are multipolar and link other neurons. Interneurons conduct impulses from one part of the brain or spinal cord to another part
Sensory Neurons
Sensory neurons are a type of neuron that transmits sensory information from sensory organs and receptors to the central nervous system. Sensory neurons either have specialized receptor ends at the tips of their dendrites or have dendrites closely associated with receptor cells in the skin or in the sensory organs
Unipolar Neurons
Has a single process extending from the cell body, a short distance from the cell body, separates into two branches. One branch associates with dendrites and the other enters the brain or spinal cord.
Bipolar Neurons
Have two processes, one is an axon and the other a dendrite.
Multipolar Neurons
have many processes, only one process is an axon, and the rest are dendrites.
Cerebrum
Largest part of the brain, responsible for consciousness, thought, and voluntary movement
Mixed Nerves
Have both sensory and motor fibers
Motor Nerves
Conduct impulses to muscles or glands
Sensory Nerves
Sensory nerves carry signals to your brain to help you touch, taste, smell and see.
Know the major meninges of the brain
- Dura mater: This is the outer layer, closest to your skull.
- Arachnoid mater: This is the middle layer.
- Pia mater: This is the inner layer, closest to your brain tissue.
-Know what neurilemma are and why they are important
The neurilemma is a sheath that surrounds the myelin sheath. The neurilemma are important because they play a vital role helping the axons of peripheral nerves regenerate.
Know the differences between the autonomic and somatic nervous system
Your somatic nervous system involves things you can consciously sense and do. Your autonomic nervous system works without you thinking about it, running the behind-the-scenes processes that keep you alive.
-Know the difference between the peripheral nervous system and the central nervous system.
The CNS consists of the brain and spinal cord. Whereas the PNS includes the cranial and spinal nerves that connect the CNS to other parts.
-Know the components of neurons and their functions
- A neuron is composed of dendrites(function to receive information), an axon(functions to send impulses away from cell body and to neurons or cells) , and a cell body or soma (functions to maintains shapes of the cell and ensure proper diameter of the axon).
Cerebellum
“little brain,” controls coordination and balance
Brainstem
Connects the brain to the spinal cord, and regulates vital functions such as breathing and heart rate
Diencephalon
Located deep within the brain, includes thalamus and hypothalamus, regulates body functions (temp. and hunger)
Astrocytes
star-shaped cells, most numerous of glial cells, prevents capillary leakage, and plays a major role in the maintenance of the blood-brain barrier
