Module 3 - Nervous System Flashcards
What are the components of the Central nervous system
(CNS)?
Brain and Spinal cord
What is the function of the Central nervous system (CNS)?
receives, processes, and transfers information
What are the components of the PNS?
the nerves outside the CNS
How many divisions is the Peripheral nervous system (PNS)? What is the function of the divisions.
– Sensory division: carries information towards the CNS
– Motor division: carries information away from the CNS. (-Somatic and autonomic divisions)
What do neurons generate?
generate action potentials (electrical impulse).
-initiate and transmit action
potentials
-primary means of communication throughout
the nervous system
What makes up a neuron? (3)
Soma, Dendrites, Axon
What is a Soma?
cell body with nucleus and organelles
What are Dendrites?
receive incoming information
What is an Axon?
long; conduct electrical impulses away from the cell body
What is the function of neuroglial cells?
support and protect (insulation) neurons
What percent of Neurons and Neuroglial cells make up the nervous system?
Neurons = 20%
Neuroglial cells = 80%
T/F: Neuroglial cells do NOT transmit action potentials
True
What are examples of Neuroglial cells?
Schwann cells & Oligodendrocytes
Which cells form the myelin sheath in PNS?
Schwann cells
What is the role of myelin sheath?
Speed up the transmission of nerve impulses by facilitating saltatory conduction
What is saltatory conduction?
leaping pattern of action potential conduction
FASTER!
What disease develops if the myelin sheath is progressively damaged? What are some symptoms of the disease?
Multiple Sclerosis
Symptoms: weakness, visual impairment, and incontinence.
Neurons come together to form ____.
Nerves.
What is a nerve?
A nerve contains axons of many neurons wrapped together in a protective sheath.
A nerve carries information to and from the CNS.
How many cranial nerves do we have?
12 pairs of cranial nerves
(connected to brain)
How many spinal nerves do we have?
31 pairs of spinal nerves
(connected to spinal cord)
The PNS is split into Sensory division and Motor division. What is Motor division split into?
Somatic and autonomic divisions
What are the functions of Somatic division? (2)
-Voluntary: Conscious control of skeletal muscles
–Involuntary: (reflexes)
What are the functions of Autonomic division?
-automatic body functions: enervate smooth muscle, cardiac muscle, and internal organs
The PNS is split into Sensory division and Motor division. Motor division is split into Somatic and Autonomic divisions. What is Autonomic division split into?
Sympathetic division and Parasympathetic division
What is Sympathetic division?
– Prepares the body for
emergencies
– FIGHT/FLIGHT
Signs of Sympathetic division
– Increases heart rate and
respiration
– Raises blood pressure
– Dilates pupils
– Slows digestion and urine
production
What is Parasympathetic division?
- Relaxes the body
Signs of Parasympathetic
division
– lowers heart rate and respiration
– increases digestion
– permits urination
T/F: Sympathetic and parasympathetic divisions oppose one another to maintain homeostasis
TRUE
What provides the Central Nervous System with protection? (3)
Cranial Bones, Meninges, and Blood-brain barrier.
What is Meninges? Name 3.
membranes, layers that separate the brain from the actual cranial bones.
- Dura mater = thick fascial layer
- arachnoid = thin
- pia mater = thin and clear
What does the Blood-brain barrier do?
blocks some chemicals and pathogens
some particles and molecules are not able to cross the BBB
What are the 3 basic parts of the Hindbrain?
– Medulla oblongata
– Cerebellum
– Pons
What does the Medulla oblongata do?
– Connects to spinal cord
– Controls vital automatic
functions of internal organs
– Right brain controls left side of body
– Left brain controls right side of body
What does the Cerebellum do?
– Coordinates basic body movements (Putting on shoes; typing; how to hold a football)
– Alcohol impacts cerebellum function
What does the Pons do?
– Connects brain centers to the spinal cord
– Helps monitor breathing
What does the Midbrain do?
▪ Coordinates movements of the head related to vision and hearing
▪ Controls movement of eyes and size of pupils
▪ Includes groups of neurons involved in sleep/wakefulness cycles
Name each of the 4 lobes of the brain
- Occipital lobe - right underneath a baseball hat
- Temporal lobe - either side of the ears
- Parietal lobe- right behind the forehead lobe
- Frontal lobe - forehead
What is the Occipital lobe responsible for?
visual information
What is the Temporal lobe responsible for?
auditory information, spoken/written language
What is the Parietal lobe responsible for?
sensory information from the skin
What is the Frontal lobe responsible for?
motor activity, speech, conscious thought
What causes an infection of the nervous system?
Caused by viruses or bacteria that pass through the blood-brain barrier
Describe Meningitis
Inflammation of the meninges caused by viral or bacterial infection
Describe Alzheimer’s disease
an accumulation of abnormal protein, beta amyloid, causing progressive memory lapses and dementia
Describe Parkinson’s disease
a progressive degenerative disorder affecting motor activity due to loss of dopamine-releasing neurons.
