Brainscape's Knowledge GenomeTM

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


See full index

Biopsychology > neurons > Flashcards

neurons Flashcards

1
Q

where are neurons located?

A

neuropiles
nerves
brain
spinal cord

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

examples of neurons in interconnected neural networks?

A

sensory organs, motor pathways etc.

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

what is the morphological division of neurons?

A 
the CNS (brain and spine)
the PNS (everywhere else)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is cephalisation?

A

the formation of central ganglia and brains in one end of the animal body

(start of CNS)

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

which type of cord do vertebrates and invertebrates have?

A

vertebrates - dorsal

invertebrates - ventral

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

what are the main components of a neuron?

A

nucleus - containing dna

mitochondria - powerhouse of the cell

cytoplasm - contains molecules and proteins

cell membrane - polarised so enable neuron to generate electrical currents
(typical animal cells)

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

difference between anions and cations?

A

anion - negative ion so more electrons than protons

cation - positive ions so contain more protons than electrons

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

what are the 4 zones in a neuron?

A
  1. Input zone (soma and dendrite to get info from enviro)
  2. Integration zone (whether input should amount to output, between soma and axon)
  3. Conduction zone (axon)
  4. Output zone (axon terminals where signal is passed to next cell)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

describe ion channels in the neurons, where located and their purpose?

A

‘selectivity filter’ to only allow ions of certain charge and size through at certain time

located in the membrane and in specific zones in the neuron

allow neuron to generate bioelectric currents through movement of ions

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

how do ions move?

3 ways

A

DIFFUSION - when channels open
areas of high concentration to low concentration areas so down concentration gradient

-when ion channels closed:
can diffuse inside the cell and along membrane but not beyond the membrane and out of the cell

electrostatic forces: like charges repel etc.

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

what is it called when ion channels are open?

and what happens?

A

semipermeable state of neuronal membrane

ions move and pushed or pulled back depending on how the electrochemical gradient changes as ions cross the membrane

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

what happens when ion channels close?

A

non-permeable state of the neural membrane

distribution differs inside and outside of cell which forms an electrochemial gradient

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

how do ion pumps function?

A

carrier protein in cell membrane binds to from one side of the membrane and move to area of their higher conc gradient (active transport)

phosphate group detatches from ATP and produces energy to change shape of carrier protein and enable ion to be released

ions on other side bind to protein and phosphate group drops off which changes shape back to normal

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

what is the main role of ion pumps?

what are the main 2?

A

ion pumps help to restore and maintain the difference in ion concetrations inside and outside the neurons

main ones: sodium-potassium and calcium

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

what is Ohm’s law?

A

voltage = current x resistance

measured using multimeter

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

how do microelectrode recordings work?

A

When a metal electrode is inserted in an aqueous ionic solution (electrolyte), ions can react with the electrode.

The distribution of charges can be compared with that of a reference electrode

17
Q

when is a neuron inactive?

A

when it doesn’t generate signals

18
Q

what is the resting potential?

A

membrane potential of a nerve cell at rest (neuronal membrane is polarised)

19
Q

what is a neural signal?

A

change of resting potential to more negative or positive when ions move across the membrane

20
Q

graded potential:

what is hyperpolarisation?

A

a more negative membrane potential than the resting potential

(measured in millivolts)

21
Q

graded potential:

what is depolarisation?

A

a more positive membrane potential than the resting potential

(measured in millivolts)

22
Q

what is action potential?

when is the frequency high?

A

all or nothing response when the depolarisation increases above a neuron-specific threshold (never occur during hyperpolarisation)

stronger the excitation, higher the frequency (how many peaks in a given time) of action potentials generating in Hz

23
Q

what did Hodgkin and Huxley find about neuronal signals?

A

won Nobel Prize in 1963

discovered neuronal electrical signal generation

identified between resting potential and neural signal (change of resting to posiitve or negative due to ionic movement across the membrane)

length of neural signals and which ions contributing most to signals and voltage gated channels

24
Q

how do action potentials work?

6 phases

A

Resting potential: voltage gated Na+ and K+ are closed (-70mV)

Rising: depolarisation (more positive) caused by the opening of voltage gated Na+ channels and entering of Na+ into neuron in response to stimulation by pre-synaptic neuron

Overshoot: membrane potential becomes positive as more Na+ flow into the cell as more Na+ channels open towards the axon (positive feedback loop)

Falling: Na+ channels become inactivated and close but K+ channels open leading to reduction of positive charge inside the cell as K+ ions leave (repolarisation at +40mV where intracellular space becomes more negative again)

Undershoot: too much K+ flows out of cell through open K+ channels (hyperpolarisation where more negative than resting potential as too many ions have left)

Recovery: all channels then closed and membrane potential returns to resting value through leaky ion channels and sodium-potassium pump as too negative (refractory period)

25
Q

what are the main functions of the nervous system?

A 
regulate inner organs
release chemical messengers
change internal states
acquire info from in and out of body
control movementand language
26
Q

what do gated ion channels do?

A

closed until activated

by electrical signals: (voltage gated) located at axon hillock

by drugs: (ligand gated) located at dendrites or cell body

27
Q

what are leak channels?

A

always open but only allow specific ions to freely diffuse

28
Q

what are the 3 classes of ion channels?

A

leak channels
gated ion channels
ion pumps

29
Q

describe the process of maintaining the correct ion concentrations?

A

diffusion through leak channels lets K+ outside

charge outside + and inside -

K+ pulled back due to electrostatic gradient

Na+ diffuses in

cytoplasm now more +

equal K+ has to flow out to maintain correct charges

30
Q

where are ion pumps and leak channels located?

A

cell membrane

31
Q

where do graded potentials occur?

A

dendrites

Biopsychology (23 decks)

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