What is the primary difference between temporal summation and spatial summation? a. spatial summation depends on contributions from more than one sensory neuron. b. only spatial summation can produce an action potential. c. spatial summation alters the response of more than one postsynaptic cell. d. temporal summation produces a hyperpolarization instead of a depolarization?

The correct answer is A, spatial summation depends on contributions from more than one sensory neuron. Spatial summation is a mechanism of eliciting an action potential in a neuron with input from multiple presynaptic cells. It is the algebraic summing of potentials from different areas of input, usually on the dendrites. Temporal summation occurs when a single presynaptic neuron fires many times in succession, causing the post-synaptic neuron to reach its threshold and fire.

1.fossils 2.analogous organs 3.homologous organs