Bi231 CH12

______ are the most numerous type of neuron in the CNS.

• Bipolar neurons

• Interneurons

• Motor neurons

• Unipolar neurons

• Sensory neurons

Branches that may occur along an axon are called

• Collaterals

• Synaptic terminals

• Telodendria

• Synapses

• Hillocks

Sensory neurons of the PNS are

• Bipolar

• Unipolar

• Multipolar

• Tripolar

• Anaxonic

The plasma membrane of an axon is called the

• Axon terminal

• Neurilemma

• Myelin sheath

• Axolemma

• Sarcolemma

_______ monitor the position of skeletal muscles and joints.

• Interoceptors

• Proprioceptors

• Exteroceptors

• Photoreceptors

• Pressoreceptors

Most neurons lack _______ and so are permanently blocked from undergoing cell division.

• endoplasmic reticula

• cytoplasm

• centrioles

• a nucleus

• ribosomes

The part of the peripheral nervous system that carries sensory information to the CNS is designated

• somatic.

• motor.

• autonomic.

• afferent.

• efferent.

Graded potentials

• may be either a depolarization or a hyperpolarization.

• are always a depolarization.

• are always a hyperpolarization.

• do not affect membrane potential.

When potassium channels open and the ions diffuse through the membrane,

• the membrane will depolarize to threshold.

• the inside of the membrane will become more positive.

• the inside of the membrane will become more negative.

• the membrane will become depolarized.

• there will be almost no effect on transmembrane potential.

The period during which an excitable membrane cannot respond to further stimulation is the _______ period.

• stationary

• resting

• absolute refractory

• lag

• relative refractory