Nervous Tissue Flashcards
ID 3 basic functions of the nervous system in maintaining homeostasis
Sensory, integration, motor
__NS is brain & spinal cord
CNS
__NS is everything traveling toward or away from the CNS
P
In PNS, impulses traveling toward the CNS are _______ or sensory. Impulses traveling away from the CNS are _________ or motor
Afferent
efferent
If the impulses are going to your skeletal muscle, they would be somatic efferent. If the impulses are going to smooth muscle, cardiac muscle or glands they are _________ efferent = _________
Visceral efferent, ANS
____________ – receiving end or receptor end, may have many; Cell body – location of the organelles such as nucleus, mitochondria…; ____________ – conducting end sending messages away from the cell body.
Dendrite
Axon
___________ are a clump of cell bodies of neurons in the CNS and ___________ are clumps of cell bodies in the PNS
Nuclei
Ganglia
Myelin is a fatty substance wrapped in layers around an axon. The myelin is made by__________ in the PNS and_____________ in the CNS.
Schwann cells
Oligodendrocytes
____________ can make a regeneration tube which is a scaffolding for the cut ends of the axon to follow during regeneration.
Schwann cells
The ____________ are between the blood and the brain cells. Thus a poison would not go directly to the brain from the blood
Astrocytes
About half of nervous tissue is supportive cells called ________. This includes the Schwann cells, oligodendrocytes and astrocytes.
Neuroglia
____________, found only in the PNS are groups of axons.
Nerves
____________: neuron has one axon and one dendrite,
____________– the most common (e.g. motor neurons) have numerous dendrites and one axon
_____________ have one extension that branches into the dendrite and the axon and are found in sensory neurons.
Bipolar
Multipolar
Unipolar
_____________ summation is summation in time. If at a synapse you have one EPSP and another one rapidly follows & then another one… you will likely have enough depolarization to reach threshold.
___________ summation is summation in space. This would occur in a situation such as convergence where each presynaptic neuron releases a little bit of neurotransmitter going to the post synaptic neuron and all of the pre’s together will add their neurotransmitter together & it will likely be enough to reach threshold in the postsynaptic neuron and send the message along its way.
Temporal
Spatial
The dendrite is the receiving end of the neuron. Its job is to take the stimulus and turn it into depolarization which is what the neuron understands. The more dendrites stimulated, the______________ the stimulus. Also, a strong stimulus will send a high frequency of impulses to the brain.
Stronger
