Nervous System Flashcards
What are the two major divisions of the nervous system?
Central nervous system and peripheral nervous system
What major structures does the central nervous system consist of?
Brain and spinal cord
What are the two nervous system divisions of the peripheral nervous system that controls voluntary and involuntary motor activity
Somatic nervous system (voluntary) and autonomic nervous system (involuntary)
What are the two divisions of the peripheral nervous system that sends sensory and motor information to and from the body and the central nervous system?
Afferent(sensory) and efferent(motor)
What type of information does the afferent division of the peripheral nervous system send
Sensory information from the body to the central nervous system includes visual, receptors, auditory receptors, chemo, receptors, and somatosensory or touch receptors
What type of information does the efferent division of the peripheral nervous system send
Motor information from the central nervous system to the body through the somatic and autonomic nervous system’s
What efferent information is sent via the somatic nervous system?
Voluntary and involuntary contraction of skeletal muscle, for stability and mobility of the body
What efferent information is sent via the autonomic nervous system?
Involuntary activation of smooth muscles for functioning of the internal organs
What are the two main types of cells in the nervous system?
Neurons and glial cells
What is the end of the axon that meets the dendrites at the synapse called?
Axon terminal
What is the electrical signal sent down the axon of a neuron called
Action potential
Are motor neurons typically unipolar multipolar and what does that mean?
Multi polar, they have two or more dendrites, and a single axon
What is myelin?
A Phatty protective sheets wrapped around the axons of some neurons that help to speed up electrical signals, known as action potential’s
What type of cell form is Myelin in the central nervous system?
Oligodendrocytes
What type of cell forms myelin in the peripheral nervous system?
Schwann cells
What is the name for bundles of axons within the central nervous system?
Tract
What is the function of the blood brain barrier?
It is a highly selective membrane lining the capillaries in the brain that lets in water, oxygen glucose and other smaller molecules, while keeping most others out to protect the brain from foreign invaders
What is the function of the two cerebral hemispheres of the brain?
The right cerebral hemisphere receives sensory fibers and sends motor fibers to the left side of your body
The left cerebral hemisphere receives sensory fibers and sends motor fibers to the right side of your body
What is the gray matter in the brain made of
Neuron cell bodies
What is the white matter in the brain made of?
Axons of neuron cell bodies
What is the function of the hypothalamus?
It is a small region that does a variety of things like regulate the body temperature for sleep, and wake cycle and eating and drinking by regulating the release of the major endocrine hormones
What is the function of the pituitary gland?
Produce and secrete hormones, when it receives signals from the hypothalamus
What is the function of the cerebellum?
It helps with coordinating movement, precision and balance
What is the function of the brain stem?
It controls, vital life functions like blood pressure, breathing consciousness, sleep wake, cycles, postural, control, facial expressions, blood pressure, swallowing, coughing, vomiting, and digestion
What is the function of the spinal cord?
It is a long ride of nervous tissue that extends down from the brainstem to the lumbar region of the vertebral column. Information travels up through sensory fibers and down through motor fibers.
What are the three gray matter paired horns that are seen in a cross-section of the spinal cord?
Anterior or ventral horn’s posterior, or dorsal horns and lateral horns
What is the function of the anterior or ventral horns of the spinal cord?
They receive information from the motor cortex of the brain and then send it to the skeletal muscle to trigger voluntary movement
What is the function of the posterior or dorsal horns of the spinal cord?
They receive sensory information from the outside world and send it to the sensory cortex of the brain
What is the function of the lateral horns of the spinal cord?
They are mainly involved with the sympathetic division of the autonomic motor system. These help regulate processes like urination, digestion and heart rate.
How is the spinal cord involved in coordinating reflexes?
Some sensory neurons synapse in the spinal cord, and can produce fast involuntary motor responses to sensory stimulus
What is the function of cerebrospinal fluid?
It is a clear watery liquid, which is pumped around the spinal cord, and the brain cushioning them from impact and bathing them in nutrients
What are the two major types of peripheral nerves found in the peripheral nervous system
Cranial nerves and spinal nerves
How many cranial nerve pairs are there in the body and what do they innervate?
There are 12 and they innervate the head and neck
How many spinal nerve pairs are there in the body and how are they classified?
- Spinal nerve pairs.
Eight. Cervical.
12 thoracic
Five lumbar
Five sacral
One coccygeal
What is the general path of sensory nerves in the somatic nervous system division of the peripheral nervous system?
Sensory nerves which have axons that carry sensory information from the peripheral tissues, like the skin back to the cell bodies in the posterior horns of the spinal cord
What is the general path of the motor nerves in the somatic nervous system division of the peripheral nervous system?
Motor nerves contain the axons that carry motor information from the cell bodies in the anterior horns of the spinal cord to the neuromuscular junction, which is where these axons contact the skeletal muscle cells
What are the divisions of the autonomic nervous system and the peripheral nervous system?
Sympathetic and parasympathetic
What are the cell bodies of preganglionic neurons of the autonomic nervous system located
In nuclei in the lateral horns of the spinal cord
What are the cell bodies of postganglionic neurons of the autonomic nervous system located?
In ganglia outside of the spinal cord
What is the general path of motor nerves in the autonomic nervous system division of the peripheral nervous system?
Signals are sent from the hypothalamus to preganglionic neurons, which exit the spinal cord to reach the ganglia and synapse with the postganglionic neurons. Then the axons of postganglionic neurons exit the ganglia to reach the organs and synapse with the target organ cells.