Quiz 2 nervous system part 1

Question 1

Neuromuscular junction

Answer 1

motor neuron synapsed onto a skeletal muscle fiber

Question 2

simple circuits

Answer 2

consist of a sensory neuron synapsed onto a motor neuron.

Question 3

complex circuits

Answer 3

have one or more interneurons to integrate and transmit signals

Question 4

electricity review

Answer 4

law of conservation of electrical chargers
-opposite charges attract; like charges repel each other
-separating positive charges from negative charges requires energy
-conductor vs insulator

Question 5

membrane potentials

Answer 5

caused by unequal Distibution of charges
-concentration gradient of ions
-membrane permeability to those ions
- the phospholipid bilayer itseld is impermeable to ions
-leak vs gated

Question 6

polarized

Answer 6

at rest, cells carry negative charge ECF

Question 7

depolarization

Answer 7

when a change occurs inside a cell that causes the distribution of electric charges to alter, leaving the cell with a less negative charge than the outside

Question 8

repolarization

Answer 8

a stage of an action potential in which the cell experiences a decrease of voltage due to the efflux of potassium (K+) ions along its electrochemical gradient

Question 9

hyperpolarization

Answer 9

when the membrane potential becomes more negative at a particular spot on the neuron’s membrane

Question 10

The Nernst equation

Answer 10

the membrane potential that a single ion would produce if the membrane were permeable to only that ion

Question 11

the Goldman equation

Answer 11

predicts membrane potential that results from the contribution of all ions that can cross the membrane.

Question 12

propagation speed

Answer 12

how fast an action potential propagates down an axon is influenced by
-diameter of axon
-larger axons are faster
-resistance of axon membrane to ion leakage out of the cell
-myelinated axons are faster
-saltatory conduction between nodes of ranvier
-temperature
-10 degrees increase can double conduction velocity for frogs

Question 13

synapese

Answer 13

-connection between cells that transmit signals
come in three forms
-ionotropic
-metabotropic
-electrical synapse

Question 14

ionotropic

Answer 14

-fast
-signal transmission
-excitation(fast EPSP), inhibition (fast IPSP)

Question 15

metabotropic

Answer 15

slow
-signal transmission, neuronal modulation
-excitation (slow ESPS), inhibition (slow IPSP) other (cytoplasmic and genetic effects)

Question 16

electrical synapse

Answer 16

-instantaneous current flow
-electrical transmission
-electrical coupling
-ions flow directly between cells through gap junction
-important for cardiac muscle contraction

Question 17

chemical synapses

Answer 17

-action potential triggers neurotransmitter release
-neurotransmitters acts as ligands for receptors on post synaptic cell

Question 18

Axon

Answer 18

portion of a nerve cell(neuron) that carries nerve impulses away from the cell body

Question 19

Axon hilock

Answer 19

axon nerve fiber that is a long projection of neuron that carries the outbound neuronal cell signals

Question 20

Dendtrites

Answer 20

short, branched extension of a nerve cell along with impulses received from other cells at synapse are transmitted to the cell body

Question 21

soma

Answer 21

central part of a nerve cell that contains the nucleus

Question 22

unipolar neurons

Answer 22

only has one nerve process extending from the cell body; an axon that extends into dendrites

Question 23

bipolar neurons

Answer 23

neuron with only two extensions
- an axon and a dendrite that run from opposite sides of the cell body

Question 24

multipolar neurons

Answer 24

most common types of neurons in the CNS;
they form the autonomic ganglia.
- more than two processes emanating from the neuron cell body

Question 25

pseudounipolar neurons

Answer 25

develop as bipolar neurons with two processes extending from the cell body, one to the spinal cord and the other to the peripheral targets

Question 26

motor neurons

Answer 26

a nerve cell forming part of a pathway along which impulses pass from the brain or spinal cord to a muscle or gland.

Question 27

inter neurons

Answer 27

a neuron which transmits impulses between other neurons, especially as part of a reflex arc

Question 28

sensory neurons

Answer 28

the nerve cells that are activated by sensory input from the environment

Question 29

Post synaptic potentials

Answer 29

ionotropic responses can cause different PSP
-depolarization - excitatory
-inflex of charges
-hyperpolarization - inhibitory
-influx of - charges

Question 30

neuronal cell body

Answer 30

often a major site of integration of synaptic potential