Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physiology > Nervous system > Flashcards

Nervous system Flashcards

1
Q

What is the function of the nervous system ?

A
  1. Maintaining homeostasis. Regulate and coordinate physiology
  2. Receiving sensory input. Monitor internal and external stimuli
  3. Integrating information. Brain and spinal cord process sensory input and initiate responses
  4. Controlling muscles and glands
  5. Establishing and maintaining mental activity. Consciousness, thinking, memory, emotion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the components of the nervous system ?

A

Brain, spinal cord, sensory receptors.

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

What are the two subdivision of the nervous system.

A

Central nervous system (CNS) : brain and spinal cord

Peripheral nervous system (PNS) : sensory receptors and nerves.

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

The periphery nervous system includes …

A

Sensory receptors , nerve, ganglion and plexus.

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

Sensory receptors

A

ending of neurons or separate, specialized cells that detect such things as temperature, pain, touch, pressure, light, sound, odors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Nerve

A

a bundle of axons and their sheaths that connects CNS to sensory receptors, muscles, and glands

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

what are the 2 division of the nerve ?

A

cranial nerves: originate from the brain , 12 pairs

spinal nerves: Originate from spinal cord, 31 pairs

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

ganglion

A

collection of neuron cell bodies in PNS.

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

Plexus

A

extensive network of axons, and sometimes neuron cell bodies, located in PNS

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

What are the divisions of the PNS ?

A

Sensory ( afferent)

Motor (efferent)

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

Sensory (afferent)

A

Afferent = towards
Transmit action potentials from sensory receptors to CNS .
ex : If you feel scorching heat on your hands, the message will travel through your afferent pathway to CNS.

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

Motor (efferent )

A

efferent = away

transmits action potentials from CNS to effectors ( muscles, glands)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

motor division is divided into 2.

A

somatic nervous system and autonomic nervous system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Somatic nervous system

A

from CNS to skeletal muscles
- voluntary (consciously control movement of our skeletal muscles.
- cell body located in CNS and axons extend out via nerves to skeletal muscles.
so, single neuron system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Synapse

A

junction of a nerve cell with another cell.

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

what is a neuromuscular junction

A

is a synapse between a neuron and skeletal muscle cell.

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

Autonomic division system. (ANS)

A
  • from CNS to smooth muscle, cardiac muscles and certain glands.
  • Involuntary control
  • Have a 2 neurons system : 1st - from CNS to ganglion, 2nd - from ganglion to effector.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Autonomic nervous system is divided into 2 ;

A

1) Sympathetic
2) Parasympathetic
3) enteric

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

Sympathetic

A

Prepares body for physical activity

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

Parasympathetic

A

regulates resting or vegetative functions such as digesting foods or emptying of the urinary bladder.

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

Enteric

A

Can control the digestive tract independently of the CNS, but still considered part of ANS because of the parasympathetic and sympathetic neurons that contribute.

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

What is the organization of the nervous system.

A

Receptors –> sensory –> Central Nervous system –> MNS –> Effector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

glial cells

A

support and protect neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

neurons

A

receive stimuli and transmit action potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

nissi substance

A

its a chromatophilic substance in the cell cell body.

Has rough ER, primary site of protein synthesis.

26
Q

Dendrites

A

short, often highly branched , which have receptors for neurotransmitters - receive information from other nerve cell

27
Q

dendritic spines

A

little protuberance where axons synapse with dendrite.

28
Q

trigger zone of an axon

A

site where action potentials are generated; axon hillock and part of axon nearest cell body

29
Q

types of neurons : Structural classification

A

Multipolar , bipolar and unipolar.

30
Q

Multipolar

A

most neurons in CNS, motor neurons

- Have many dendrites and one axon

31
Q

Bipolar

A

Sensory in retina of the eye and nose

- one dendrite and one axon.

32
Q

Unipolar

A

single process that divides into two branches. Part that extends to the periphery has dendrite-like sensory receptors.
and the other branch extend s to the CNS

33
Q

Types of neutrons : Functional classification

A

sensory neurons , motor and interneurons

34
Q

interneurons

A

within CNS from one neutron to another

35
Q

Glial cells of CNS : Astrocytes

A

Processes form feet that cover the surfaces of neurons and blood vessels and the pia mater.( is a membrane covering the outside of the brain and spinal cord)
• Regulate what substances reach the CNS from the blood (blood-brain barrier). Microfilaments for support.
• Produce chemicals that promote tight junctions to form blood-brain barrier

36
Q

Blood-brain barrier

A

protects neurons from toxic substances, allows the exchange of nutrients and waste products between neurons and blood, prevents fluctuations in the composition of the blood from affecting the functions of the brain.
• Regulate extracellular brain fluid composition
- Hence, det. what substances can pass from the blood into the nervous tissue of the brain and spinal cord.

37
Q

Glial cell: Ependymal cells

A

line ventricles of brain and central canal of spinal cord and cilia help to circulate cerebral spinal fluid.
- Specialized versions of ependymal form choroid plexuses which help to form CSF.

38
Q

Choroid plexus

A

within certain regions of ventricles. Secrete cerebrospinal fluid. Cilia help move fluid thru the cavities of the brain. Have long processes on basal surface that extend within the brain tissue, may have astrocyte-like functions.

39
Q

Microglia

A

specialized macrophages. Respond to inflammation, phagocytize necrotic tissue (dead tissue), microorganisms, and foreign substances that invade the CNS.

40
Q

Oligodendrocytes

A

form myelin sheaths if surrounding axon. Single oligodendrocytes can form myelin sheaths around portions of several axons.

41
Q

Schwann Cells

A

wrap around portion of only one axon to form myelin sheath. Wrap around many times. During development, as cells grow around axon, cytoplasm is squeezed out and multiple layers of cell membrane wrap the axon.

42
Q

Satellite cells

A

surround neuron cell bodies in sensory ganglia, provide support and nutrients

43
Q

Myelinated axons

A

-Myelin protects and insulates axons from one another, speeds transmission, functions in repair of axons.
– Not continuous

44
Q

Nodes de Ranvier

A

– Completion of development of myelin sheaths at 1 yr. but NOT all parts of the brain are fully myelinated until adulthood (when does it complete?)
– Degeneration of myelin sheaths occurs in multiple sclerosis and some cases of diabetes mellitus.

45
Q

Unmyelinated axons

A

rest in invaginations of Schwann cells or oligodendrocytes. Not wrapped around the axon; gray matter.

46
Q

Grey matter

A

unmyelinated axons, cell bodies, dendrites, glia. Integrative functions

47
Q

White matter

A

myelinated axons. Nerve tracts propagate action potentials from one area in the CNS to another
( Axons)

48
Q

Where is the gray and white matter located in the brain ?

A

gray is outer cortex as well as inner nuclei (this represents groups of neuron cell bodies); white is deeper.

49
Q

Where is the grey and white matter located in the spinal cord ?

A

white is outer, gray is deeper.

50
Q

ganglia

A

PNS gray matter is groups of cell bodies

51
Q

Action potential

A

Its an electrical signal that is produce by the cell
• Transfer of information from one part of body to another
• Electrical properties result from ionic concentration differences across plasma membrane and permeability of membrane

52
Q

What causes the ion concentration difference across the membrane ?

A

• These ion concentrations are a result of two processes: the Na+/K+ pump and membrane permeability. Note high concentration of Na and Cl- ions outside and high concentration of K+ and proteins on inside. Note steep concentration gradient of Na+ and K+, but in opposite directions.

53
Q

Ligand gated channel

A

requires that a molecule (drug or neurotransmitter) binds to a receptor to cause it to open; receptors are usually protein or glycoprotein
- ex : acetylcholine binds to acetylcholine receptor on a Na+ channel. Channel opens, Na+ enters the cell.

54
Q

gated ion channels

A

open and close because of some sort of stimulus. When they open, they change the permeability of the cell membrane.

55
Q

Proteins and Cl-

Permeability

A

Proteins: synthesized inside cell: Large, don’t dissolve in phospholipids of membrane. Proteins are negatively charged.
• Cl- are repelled by proteins and they exit thru always-open nongated Cl- channels (leak channels).

56
Q

Leak ion channels

A

Many more of these for K+ and Cl- than for Na+. So, at rest, more K+ and Cl- are moving than Na+.
• How are they moving? Protein repels Cl-, they move out. K+ are in higher concentration on inside than out, they move out.
– Always open and responsible for permeability when membrane is at rest. – Usually specific for one type of ion although not absolute.

57
Q

Voltage gated channel

A

open or close in response to small voltage changes across the cell membrane.

58
Q

At rest, is it more negative in the inside or outside ?

A

• At rest, membrane is negative on the inside relative to the outside.

59
Q

What happens when cells are stimulated ?

A

When cell is stimulated, that relative charge changes and voltage-gated ion channels either open or close. Most common voltage gated are Na+ and K+. In cardiac and smooth muscle, Ca2+ are important.

60
Q

Speed of conduction

A

Faster in myelinated than in non-myelinated
• In myelinated axons, lipids act as insulation forcing ionic currents to jump from node to node
• In myelinated, speed is affected by thickness of myelin sheath
• Diameter of axons: large-diameter conduct more rapidly than small-diameter. Large have greater surface area and more voltage-gated Na+ channels

Physiology (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions