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Flashcards in Lab exam 3 Deck (46):
1

what system anazles sensory information, stores information and makes decisions?

nervous system

2

an impulse from one nerve cell is communicated to another nerve cell via the ____

synapse

3

where are bipolar neurons commonly found?

in the retina of the eye

4

what affects the velocity and duration of muscle contraction?

load on the fiber

5

what is the most distinguishing characteristic of muscle tissue?

the ability to transform chemical energy into mechanical energy

6

where are ciliated CNS neuroglia that play an active role in moving the cerebrospial fluid called?

ependymal cells

7

the period after an initial stimulus when a neuron is not sensitive to another stimulus is the ______

absolute refractory period

8

an anerobic metabolic pathway that results in the production of two net atps per glucose plus two pyruvic acid molecules is called

glycolysis

9

after nervous stimulation stops what prevents ACh in the synaptic cleft from continuing to stimulate contraction?

acetylcholinesterese destroying the ACh

10

what happens when an EPSP is being generated on the dendritic membrane?

a single type of channel will open, permitting simultaneous flow of sodium and potassium

11

a second nerve impulse cannot be generated until?

the membrane potential has been reestablished

12

what is true about ions moving across excitable living membranes

sodium gates in the membrane can open in response to electrical potential changes

13

are neruons mitotic?

no

14

collections of nerve cell bodies outside the central nervous system are called

ganglia

15

fatigued muscle cells that recover rapidly are the products of

intense exercise of short duration

16

what does myoglobin store?

oxygen in muscle cells

17

neuroglia that control the chemical enviornment around neurons by buffering potassium and recapturing neurotransmitters are ___

astrocytes

18

what describes the excitatory postsynaptic potential?

short distance depolarization

19

what muscle is long and cylindrical with many nuceli?

straiated muscle cells

20

the strongest muscle contractions are normally achieved by

increasing the stimulation up to the maximal stimulues

21

the part of a neuron that conducts impulses away from its cell body are called

axon

22

is innervation of skeletal muscle a function of the ANS?

NO

23

excitation-contraction coupling requires which of the following substances?

Ca2+ and ATP

24

if a motor neuron in the body were stimulated by an electrode places about midpoint along the length of the axon

the impulse would spread bidirectionally

25

what does excess postexercise oxygen consumption represent?

the difference between the amount of oxygen needed for totally aerobic muscle activity and the amount actually used

26

which of the following is not a function of astrocytes

provide the defense for CNS

27

The giant protein titin maintains the organization of the _________ assisting in muscle stretching

A band

28

which muscle has one nucleus, no sarcomerese and rare gap junctions

multiunit smooth muscle

29

IPSP is associated with ___________-

hyperpolarization

30

in what way does the interior surface of a cell membrane of a resting neuron differ from the external enviornment. the interior is _______

negatively charged and contains less sodium

31

what is the role of tropomyosin

its a contraction inhibitor by blocking mysoin

32

in an isotonic contraction

the muscle changes in length and moves the 'load"

33

schwann cells are functionally similar to

oligodendrocytes

34

the mechanism of contraction in smooth muscle is different from skeletal muscle in that

the site of calcium regulation differs

35

what is not a role of ionic calcium in muscle contraction?

activates epinepherine released from adrenal gland

36

the term central nervous system refers to the

brain and spinal cord

37

saltatory conduction is made possible by the

myelin sheath

38

motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle and glands

ANS

39

What is the primary function of wave summation?

produce smooth, continuous muscle contraction

40

which ion channel opens in response to a change in membrane potential and participates in the generation and conduction of action potentials

voltage-gated channels

41

the sliding filament model of contraction involved

actin and myosin sliding past eachother and partially over lapping

42

the substance released at axon terminals to propogate a nervous impulse is called a

neurotransmitter

43

during vigorous exercise, there may be insufficient oxygen available to completely break down pyruvic acid for energy. as a result, the pyruvic acid is converted to

lactic acid

44

muscle tone is

a state of sustained partial contraction

45

smooth muscle is characterized by all of the following except

there are more thick filaments than thin filaments

46

can smooth muscle cells divide to increase their numbers?

yes