Anatomy Two: Exam Two (Chapter 11)

Which part of a neuron makes proteins and packages them into vesicles?

Cell body

The division of the nervous system that is the key decision maker of the body is the ______ nervous system.

Central

Synapses in which neurotransmitters are released are called _______ synapses.

Chemical

When several input nerve fibers synapse with fewer postsynaptic neurons, this is called a _____ Pathway.

Convergent

Oligodendrocytes...

Form myelin sheath around part of the axon in the PNS

A group of related nerve cell bodies is located outside of the central nervous system. It is called a?

Ganglia

Cell bodies of the peripheral nervous system are located in

Ganglia

Cell bodies of the peripheral nervous system are located in __________, cell bodies of the CNS are located in _______________

Ganglia Gray Matter

The knotlike swelling in a nerve where neuron cell bodies are found is called a?

Ganglion

The cells that account for over half of the brain's weight and outnumber neurons by at least 10 times are called _______ cells

Glial

Electrically excitable cells use the difference of _______ across the cell membrane to carry out their functions.

Ions

Cytoplasm ______ electrically neutral.

Is

Microglia

Macrophage (Phagocytic) cells in CNS

When the resting membrane potential becomes more ______ the condition is referred to as hyperpolarization.

Negative

Soma is also known as?

The cell body of a Neuron

Place the events of action potential propagation in an unmyelinated axon

1) Generation of an initial action potential 2) Generation of a local current in membrane adjacent to initial action potential 3) Plasma Membrane adjacent to initial action potential depolarizes 4) Plasma Membrane reaches threshold 5) Generation of next action potential

There are _____ pairs of cranial nerves and _____ pairs of spinal nerves.

12, 31

The electrical signals that are propagated along axons, regulating and coordinating body activities, are known as?

Action Potentials

A stimulus either causes an action potential or it doesn't.

All-Or-None Repsonse

Which of the following events will lead to depolarization?

An increase in K+ in the extracellular fluid

Dendrites...

Are the input part of the neuron

A neuroglial cell that is a major component of the blood-brain barrier is the

Astrocyte

Polysynaptic reflex

At least one interneuron between sensory neuron and motor neuron

The self-governing division of the motor division of the nervous system is the ______ nervous system.

Autonomic

Cytoplasm of an axon is called an?

Axoplasm

The function of acetylcholinesterase is to

Breakdown acetylcholine in the synapse.

Acetylcholine ______ bind to norepinephrine receptors.

Cannot

Branched cytoplasmic extensions of the neuron that receive input and transmit signals toward the cell body are?

Dendrites

Synapses in which gap junctions allow ions to diffuse quickly from cell to cell are called _______ Synapses

Electrical

Cerebrospinal fluid is produced by _________ cells.

Ependymal

Two cells that make up the nervous system:

Neurons Glial cells

Rough endoplasmic reticulum of a neuron responsible for protein synthesis?

Nissl body

Gaps or interruptions in the myelin sheath are called

Nodes of Ranvier

Which of the following neuroglial cells is being damaged in multiple sclerosis

Oligodendrocytes

The subdivision of the nervous system that consists of nerve tissue external to the central nervous system is the ______ nervous system.

Peripheral

What are the two neuroglial cell types found in the Peripheral Nervous System?

Satellite Cells Schwann Cells

At a synapse, the neuron that responds to the neurotransmitter is the _____ neuron

Postsynaptic

Enlarged end of axon containing vesicles filled with neurotransmitters

Presynaptic terminal

The purpose of the absolute refractory period is to?

Prevent action potentials from being generated in reverse direction

Identify the structural types of neurons.

Pseudo-unipolar Multipolar neuron Bipolar neuron

Ipsilateral reflex arc

Reflex arc does not cross the spinal cord

Monosynaptic reflex

Reflex pathway with only one synapse between the sensory and motor neurons (ex: knee-jerk).

A period of time after a nerve cell has responded to a stimulus in which it cannot be re-excited by a threshold stimulus is called a(n) ______ period.

Refractory

Propagation of an action potential down a myelinated axon requires that the action potential "jumps" from node to node in a process called _______ conduction.

Saltatory

Schwann cells differ from oligodendrocytes in which of the following ways?

Schwann cells form a myelin sheath around a portion of only one axon, while oligodendrocytes can surround portions of several axons.

Multipolar is a ______ classification for a neuron.

Structural

What do Glial cells do?

Supply nutrients and oxygen to neurons, To insulate one neuron from another, To destroy pathogens and remove dead neurons.

A neuron that carries action potentials from one neuron to another is called a(n)

Synapse

Contralateral

The reflex arc can occur at the same time as a withdrawal reflex - The end result is extension of the limb on the opposite side of the body.

Identify the characteristics of action potentials.

The strength of the stimulus determines the frequency of the action potentials. They are propagated in a non-decremental fashion. They are all-or-none.

Identify the statements that are true regarding the nature of the large proteins found within neurons.

They do not readily diffuse through the membrane. They are negatively charged. They are synthesized inside the cell..

A reflex that protects limbs by removing them from painful stimuli is the

Withdrawal Reflex

If the charge difference across the plasma membrane is decreased...

the membrane potential is more positive.