Chapter 7 - The Nervous System: Neurons and Synapses Flashcards
What structures store the neurotransmitter molecules in the presynaptic neuron endings?
synaptic vesicles
______ are thing branching processes that extend from the cytoplasm of the cell body
dendrites
Which of the following structures are part of the central nervous system?
brain and spinal cord
Match the label w the appropriate part of the synapse
A: terminal bouton
B: synaptic vesicle
C: synaptic cleft
Place the steps of neurotransmitter release in the correct chronological order from the point at which the action potential arrives at the terminal bouton to the diffusion of the neurotransmitter across the synaptic cleft
- Action potential causes a change in the membrane potential of the terminal bouton
- Voltage gated Ca++ channels open
- Ca++ binds to sensor proteins in cytoplasm
- Ca++ protein complex stimulates exocytosis
what is the space between the presynaptic cell and the postsynaptic cell called?
synaptic cleft
The cranial and spinal nerves are a part of the _____ nervous system
peripheral
Acetylcholine (ACh):
- is excitatory
- is a neurotransmitter
- is inhibitory
When a stimulation causes positive charges to flow into the cell and the membrane potential of the cell becomes more positive, the cell has ______
depolarized
Conduction of action potentials in a myelinated axon is:
- called saltatory conduction
- continues without decrement
- is faster than in an unmyelinated axon
A drug that is classified as an antagonist
inhibits the activity of receptor proteins
A neuromuscular junction is a synapse between a(n) ____ and a _____ cell( not second, but a type of cell)
neuron,muscle
The _____ ____ is the enlarged portion of the neuron that contains the nucleus
cell body
A drug is classified as an agonist:
activates or increase the activity of receptor proteins
All cells in the body maintain a potential difference in voltage across their membrane, called the ___ ____ _____, in which the inside of the cell is negatively charged in comparison to the outside of the cell wall
resting membrane potential
What is a neurotransmitter?
A chemical released by presynaptic nerve endings that cause changes in the membrane potential of a postsynaptic cell
What is the specialized name for the synapse between a neuron and a muscle cell?
- myoneural junction
- neuromuscular junction
A(n) is a cable like collection of axons in the peripheral nervous system
nerve
The entire nervous system is divided into the ____ nervous system and the ____ nervous system
central, peripheral
The combined electrical and concentration gradient that drives the movement of ions into and out of cells is known as the:
electrochemical gradient
changes in the permeability of the membrane are due to:
the opening and closing of ion channels
The conduction of an action potential is an unmyelinated axon:
- is conducted without decrement
- is slower than in a myelinated neuron
During excitatory synaptic transmission, neurotransmitters from the presynaptic cell bind to ligand gated channels on the postsynaptic cell causing:
- Na+ to enter the postsynaptic cell
- an EPSP
Many axons produce more than one branch, each of these _____ ____ can synapse with many other neurons
axon collaterals
The _____ is a long process of the cytoplasm that conducts impulses called action potentials away from the cell body
axon
A(n) ____ is the connection between a neuron and either another neuron or an effector cell.
synapse
What is happening when a cell undergoes repolarization?
it returns to its resting potential
what is happening when a cell undergoes hyperpolarization?
it becomes more negative than its resting potential
The highly selective barrier to diffusion that the specialized capillaries of the brain create is known as the ______ _____ barrier
blood brain
what does an EPSP do in the postsynaptic cell?
- cause action potentials to be produced
- cause the subsequent release of neurotransmitters
Neurotransmitter molecules within the presynaptic neuron endings are contained within many small membrane enclosed sacks called ______ _______
synaptic vesicles
The _____ restricts the movement of molecules from the blood to the interstitial spaces in the brain
blood-brain barrier
What type of gates or membrane channels in the postsynaptic membrane open in response to the binding of a chemical ligand to its receptor
- ligand-regulated gates
- chemically regulated gates
Which of the following cell types are neuroglial cells located within the central nervous system
- astrocytes
- oligodendrocytes
- microglia
The function of myelin is to:
- provide insulation for the axon
- prevent leakage of Na+ and K+
if a stimulation causes the inside of a cell to become more negative than its resting potential, the cell has undergone ________
hyperpolarization
What is the potential difference in voltage across the membrane of a resting cell called?
the resting membrane potential
which of the following are structural classification of neurons?
- pseudounipolar neurons
- bipolar neurons