ch 12.txt

Satellite cells, or ________ surround the neuron cell bodies in ganglia. They regulate the environment around the neuron, (like astrocyte in CNS).

Schwann cells (only in PNS) or _________ form a sheath around peripheral axons.

The outer surface of the Schwann cell is called the __________.

___________ line the central canal and ventricles. They are filled with CSF.

What are the largest and most numerous neuroglia in the CNS.

_____________ is the membranous insulation called myelin which increases the speed of the action potential. When the sheath is lined it is said to be myelinated (white matter), unmyelinated (gray matter).

__________ is a "wondering police force" and "janitorial service" engulfing cellular debris, waste products, and pathogens.

_________ are changes in the transmembrane potential that cannot spread far from the area surrounding the site of stimulation.

________ are Na+ ions that enter the cell and are attracted to the negative changes along the inner surface of the membrane.

The transmembrane potential at the ______ ______ and ______ _____ represent an integration of all the excitatory and inhibitory stimuli affecting the neuron at that moment.

Excitatory and inhibitory stimuli are integrated through interactions between _______ ______. This interaction is the simplest level of information processing in the nervous system.

The basic functional unit of the nervous system is ______.

_______ separate and protect the neurons, provide a supportive framework, act as phagocytes and help regulate composition of interstitial fluid.

The CNS consists of the ______ and the _____.

The PNS includes all the __________.

Synapses that release _______ are known as cholinergic synapses.

Synapses that release ________ are known as adrenergic synapses.

What synapse is by far the most abundant type?

Norepinephrine is also called _________ and synapses that release Ne are known as _________ synapses. Ne typically has an excitatory, depolarization effect on the post synaptic membrane.

____________ are characteristics of excitable membrane, are capable of conducting/ generating an action potential. Examples of excitable membrane: axons of unipolar and multipolar neurons. The sarcolemma of skeletal muscle fibers and cardiac muscle cells.

Nerves connected to the brain are called _______ ______.

Nerves attached to the spinal cord are called ____ ______.

The ________ division of the PNS brings sensory information to the CNS from receptors.

The _______ division of the PNS curves motor commands from the CNS to muscles and glands.

Sodium and Potassium ion channels are either passive or active. Passive channels, or _______ _____ are always _______.

Active channels, or ________ channels open and close in response to specific stimuli.

What are the 3 classes of gated channels?

Temporal is the addition of stimuli occurring in _____ ______. This occurs at a single synapse that is actively repeated.

Spatial occurs when simultaneous stimuli at different locations have a _____ _____ on the transmembrane potential. They involve multiple synapses that are active simultaneously.

What is a graded depolarization caused by the arrival of a neurotransmitter at the postsynaptic membrane?

What is a graded hyperpolarization of the postsynaptic membrane? It may result from the opening of chemically regulated potassium channels.

While this hyperpolarization continues, the neuron is said to be ______.

The ______ division has both somatic and autonomic components.

The _____ controls skeletal muscle contractions.

_______ contractions are under conscience control.

The ________ or visceral motor system provides autonomic regulation of smooth muscle, cardiac muscle and glandular secretions at the subconscious level.

The perikaryon, or ______ ______ has a coarse, grainy appearance.

The base, or ______ ______ of the axon in a multipolar neuron is attached to the cell body at the thickened region known as the ______ _______.

________ is a specialized site where the neuron communicates with another cell.

What are the largest and myelinated axons that can carry action potentials at speeds up to 140 meters per second or over 300 mph?

What are the smaller and myelinated axons that speeds average around 18 meters per second or 40 mph?

What are the unmyelinated axons that are smaller, very slow, are about 1 meter per second or 2 mph?

The Na-K exchange pump requires energy in the form of _______.

Action potential jumping from node to node rather than moving along the axon in a series of tiny steps is called ______ ______.