Ch48 Flashcards
What must multicellular organisms be able to do?
communicate between cells
What have neurons evolved to do?
Sense stimuli and move rapidly
How would you describe neuronal signaling?
long distance, electrical, specific
How would you describe hormonal signaling?
short distance, chemical, broad
Synaptic Cleft
communication point between cells
Presynaptic Cell
cell sending the message
Postsynaptic Cell
cell receiving the message
Dendrited
branched part off the soma that recieves the message from other neurons
Axon
cell extension that transmits the action potential
Soma
central part of the neuron that contains organelles
Axon Hillock
where axon and cell body meet, and where the action potential is genarated
Myelin Sheath
insulates axon and helps in signal conduction
Synaptic Terminal
end arms of the axon that transmits signal to dendrites of another neuron
how many neurons do we have in human body?
1 trillion
What are the three types of neurons?
Sensory, Inter, Motor
ALS
Amyotrophic Lateral Sclerosis; neurodegenerative disease that cause paralysis
Glial Cells
supportive cells of various types and functions, they outnumber neurons 10-50.
Astrocytes
provide structural support, regulate movement of ions and neurotransmitter concentrations, aids in nearby blood vessel dilation
Oligodendrocytes
few dendrites, but helps with myelin sheath (acts like a schwann)
What forms the sheath around the PNS axons?
Schwann Cells
What forms the sheath around the CNS axons?
Oligodendrocytes
Are cells more - or + inside?
negative
What contents are most abundant inside the cell?
potassium and proteins
what is the value of resting potential?
-70mV