Pre-Quiz 1 Flashcards

1
Q

within human organism, the two homeostasis-controlling systems are the following:

A

the CNS and PNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The central nervous system consists of

A

the brain and spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the two major classes of nervous system cells

A
  • neurons: carry/transmit information by the conduction of electrical impulses/action potentials
  • glia (neuroglia): provide support and maintenance functions for neural tissue. *unable to transmit potentials
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

neurons communicate across specialized intercellular spaces or “pipe”-like structures called

A

synapses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are the two types of synapses

A
  • electrical: no interruptions between neurons; action potentials conduct directly between adjacent cells through gap junctions
  • chemical: the plasma membranes of a presynaptic and postsynaptic neuron in a chemical synapse do not touch one another directly. The space bewteen the neurons is called a synaptic cleft which is filled with interstitial fluid. A neurotransmitter must diffuse through the interstitial fluid in the cleft and bind to receptors on the postsynaptic neuron.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what type of synapses are most abundant in the human body?

A

Chemical synapses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

name the structure of a neuron that is most effective in starting the conduction of electricity

A

neck, or axon hillock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

name the structure of a neuron that is most efficient in receiving information

A

dendrites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

the major control space of a neuron which is around the nucleus and is also called a perikaryon is

A

the soma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

where are nissal bodies found & what are they

A

they are found in the soma and are the rough ER in the plasmic reticulum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

chemical synapses can be found on which structure of a neuron

A

the synaptic bulbs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are the three types of neurons

A
  • motor/efferent (descending [from brain to organs]): they are coming out from the CNS and PNS to the effector organs and tissues. ex: contraction of skeletal muscles. They make things happen
  • sensory/afferent (ascending): they bring information from the effector organs and tissues to the PNS—> CNS for interpretation
  • associative/interneurons: complie a “balance sheet.” you can consider the a middle man. they are the majority of neurons. They connect neurons together.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

within the CNS, what type of glia cells (neuroglia )can be found?

A
  • oligodendrocytes: insulating and resist regeneration within CNS.
  • astrocytes: within CNS; form the blood-brain barrier
  • microglia: within the CNS; considered to be the sanitation department
  • ependymal cells: within the CNS; secrete CSF within brain ventricles; provide brain-CSF barrier
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

within the PNS, what type of glia cells (neuroglia) can be found?

A
  • satellite cells: within the PNS; provide support within ganglia (clusters of functionally united neurons)
  • schwann cells: insulating (organized into myelin), and assist regeneration/repair of axons within PNS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

the principal difference between the functions of neurons versus glia is what?

A

neurons transmit information by the conduction of electrical impulses/action potentials. Glia provide support and maintenance functions for neural tissue and are unable to transmit potentials.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

why is the structure of neurons’ nodes of ranvier important?

A

because schwann cells tightly insulate axons and allow the conduction of electricity to jump from node to node. It improves the speed of electricity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

the major common function of oligodendrocytes and schwann cells is

A

they both produce myelin, which acts as insulation for axons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

the major functional difference between oligodendrocytes and schwann cells is

A

schwann cells are found in the PNS and assist regeneration of axons; oligodendrocytes are found in the CNS and resist regeneration of axons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

axons with nodes of ranvier are _____; axons without nodes of ranvier are _____. Which combination is most efficient in terms of conduction speed?

A

myelinated, unmyelinated; axons with nodes of ranvier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

which division of the nervous system includes the brain and spinal cord?

A

the central nervous system, CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

within the CNS, clusters of functionally similar/related neurons are called _____.

A

nuclei

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

in the CNS, bundles of axons from the neurons of the nuclei are called _____

A

tracts

23
Q

what are the three subdivisions of the PNS

A
  • somatic nervous system
  • autonomic nervous system
  • enteric nervous system
24
Q

in the peripheral nervous system, clusters of related neurons (cell bodies or soma) are called _____

A

ganglia/ganglion

25
Q

in the peripheral nervous system, bundles of related axons are called _____

A

nerves

26
Q

somatic nervous system:

A

includes the external lining and internal lining (peritoneum) of the body wall (sensory & motor)
includes the extremities
includes the special senses (smell, taste, vision, hearing, equillibrium)

27
Q

autonomic nervous system:

A

Includes: smooth muscle, cardiac muscle, all secretory glands
Controls “primitive functions of internal milleu
subdivisions of ANS are sympathethic and parasympathetic

28
Q

enteric nervous system:

A

Chains of ganglia (plexi/plexus) along several layers of gastro-intestinal tube/alimentary canal
Responsible for peristalsis and secretion of GI juices
Is influenced/commanded by CNS and ANS

29
Q

what are the two exceptions to the somatic nervous system

A
  • goose bumps, because they are controlled by arrector pilli ssmooth muscles
  • sweat glands
    *both are controled by the ANS
30
Q

The intrinsic nervous system of the gastro-intestinal tract, which is called the ENS, is represented by the clusters of functionally related and interconnected neurons. These clustrs are subsequently called:

A
  • enteric plexus of meissner (in sub-mucosa of intestines)
  • myenteric plexus of auerbach (peristalsis in intestines)
31
Q

what are the two types of electrical signals neurons use to communicate with one another when they are electrically excitable?

A
  • action potentials
  • graded potentials
32
Q

what is a resting membrane potential

A

The resting membrane potential occurs due to a buildup of negative ions in the cytosol along the inside of the membrane and positive ions in the extracellular fluid along the outside of the membrane.
In neurons, the resting membrane potential ranges from -40 to -90 with an avg of -70

33
Q

leakage channels

A

channels that randomly alternate between open and closed positions for potassium ions. Like a revolving door

34
Q

voltage channels

A

open in response to change in membrane potential (voltage); electrical channel & therefore opens by electricity

35
Q

Ligand channels

A

open and close in resopnse to a specific chemical stimulus; usually open before electrical channels
present in interneurons and motor neurons

36
Q

mechanical channels

A

open or close in response to mechanical stimulation
present in sensory neurons

37
Q

light channels

A

open when affected by entering light (ex: eye retina)

38
Q

what is the major ion responsible for depolarization and action potentials

A

sodium

39
Q

what is the major ion responsible for the guardng/balance of the resting membrane potential

A

potassium

40
Q

what ion channels are open during the depolarization phase of action potential

A

sodium

41
Q

what ion channels are opening during re-polarization phase of action potential

A

potassium

42
Q

the main paths for flow of current across the membrane are called

A

ion channels

43
Q

ions more from _____ areas of concentration to _____ areas of concentration

A

greater; lower

44
Q

Positively charged cations move towards _____ charged areas and negatively charged anions move towards _____ charged areas

A

negatively; positively

45
Q

when the resting membrane potential is considered polarized, this means_

A

that it has potential to produce work as an electrical current, once movement of ions is allowed.
if there is potential, it is considered polarized

46
Q

what kind of channels have to open or close in order for graded potentials to occur

A

ligand-gated or mechanically gated channels have to open or close

47
Q

what happens during the depolarization phase

A

the resting membrane potential decreases towards 0 (sodium comes in)

48
Q

what happens during the repolarizing phase

A

the resting membrane potential is restored (sodium goes out, potassium comes in)

49
Q

what is a threshold

A

when depolarization reaches a ceratin level (about -55mV), and voltage gated channels open

50
Q

what is a refractory period

A

the period of time after an action potential begins during which an excitable cell cannot generate another action potential

51
Q

absolute refractory period

A

a second action potential cannot be initiated, even with a very strong stimulus

52
Q

relative refractory period

A

an action potential can be initiated, but only with a larger than normal stimulus

53
Q

what is the difference between the presynaptic neuron and the postsynaptic neuron

A

the presynaptic neuron is the neuron sending the signal
the postsynaptic neuron is the neuron recieving the message

54
Q

what are the clusters of neuronal cell bodies located in PNS and CNS?

what re the bundles of axons in PNS and CNS?

A

clusters of neuronal cell bodies
PNS: ganglion CNS: nucleus

bundles of axon
PNS: nerves CNS: tract