Ch 11- Nervous Tissue

The ________ nervous system provides involuntary regulation of smooth muscle, cardiac muscle, and glandular activity.

autonomic

The resting potential of a neuron is

-70 mV

The neurilemma of axons in the peripheral nervous system is the outer layer of

schwann cells

Which of the following is a function of the efferent division of the nervous system? A: sending signals to muscles B: integrating sensory information C: coordinating voluntary and involuntary activities D: regulating or controlling peripheral structures and systems E: providing sensation of the internal and external environments

sending signals to muscles

Bundles of CNS axons that share a common origin, destination, and function are called

tracts

Identify the correct sequence of steps in the generation of an action potential. 1. Activation of sodium channels and rapid depolarization 2. Inactivation of sodium channels and activation of potassium channels 3. Depolarization to threshold 4. Closing of potassium channels

3124

The part of the peripheral nervous system that brings information to the central nervous system is the

afferent division

The all-or-none principle states that

all stimuli great enough to bring the membrane to threshold will produce identical action potentials.

The branching structures that, together with the cell body, are sensitive to chemical, mechanical, or electrical stimulation are called

dendrites

Opening of voltage-gated sodium channels in the membrane of a neuron results in

depolarization

Which neuroglial cells produce CSF in some regions of the brain?

ependymal cells

Neurons that have two or more dendrites and a single axon extending away from the cell body are called

multipolar

A stimulus that opens gated potassium ion channels, moving the membrane voltage value below the resting potential value, results in which of the following?

hyperpolarization

Saltatory conduction A: occurs at the synapse. B: occurs only if the myelin sheath is continuous. C: is faster than conduction on an unmyelinated axon. D: occurs only if nodes of Ranvier are lacking. E: produces a stronger action potential.

is faster than conduction on an unmyelinated axon.

The myelin sheaths that surround the axons of some of the neurons in the CNS are formed by

oligodendrocytes