The Nervous System Flashcards
At the Resting membrane potential, the inside if a neuron is _______ compared to the outside?
Negative. There are more Na atoms outside the cell than K.
What type of cell produced myelin?
Oligodendrocytes in the CNS
Schwann cells in the PNS
When depolarization occurs, what happens to the membrane potential?
Na atoms flood the cell using Na channels, creating a positive membrane potential.
What occurs to the membrane potential during repolarization?
K atoms leave the inside of the cell using K channels, restoring the negative membrane potential. There is an overshoot, called hyperpolarization, and the cell then returns back to its normal membrane potential.
What’s the difference between an absolute and relative refractory period?
Absolute- no amount of stimulation will cause an action potential to occur
Relative- greater than normal amount of stimulation must occur to cause an action potential.
What is saltatory conduction?
The process of an electrochemical signal (an action potential) hopping from node to node down an axon.
Afferent neurons carry info from _____ to _____.
From the PNS to the CNS
Efferent neurons carry information from _____ to ______.
From CNS to PNS
White/gray matter of the brain is un/myelinated?
White=unmyelinated axons
Gray=myelinated axons (but unmyelinated cell bodies and dendrites)
The forebrain is divided into what two parts?
The telencephalon and the diencephalon.
The cerebral cortex is made up of what type of matter?
Gray matter, and is responsible for high level though and planning.
The diencephalon is composed of what two parts of the brain?
The thalamus and hypothalamus.
What is the role of the midbrain?
To act as an intermediate-relays sensory and visual info to the forebrain, and motor info from the forebrain to the hindbrain.
What structures make up the hindbrain?
The cerebellum, medulla, pons, which all make up the brainstem.
What 4 sections is the spinal cord divided into?
Cervical, thoracic, lumbar, and sacral.
