Tag: generation and conduction of nerve impulse

Questions Related to generation and conduction of nerve impulse

Which of the following statements are correct regarding Na+ - K+ pump?


(i) Needs energy (ATP) to work.
(ii) Expels 3 Na+ for every 2K+ ions imported
(iii) Works against a concentration gradient
(iv) Maintains resting potential

  1. (i) and (iv)

  2. (ii) and (iii)

  3. (i) and (iii)

  4. All of these


Correct Option: D

Which is wrong regarding conduction of nerve impulse

  1. In a resting neuron, the axonal membrane is more permeable to $K^+$ ions and nearly impermeable to N$a^+$ ions

  2. Fluid outside the axon has a high concentration of N$a^+$ and low concentration of $K^+$, in a resting neuron

  3. Resting potential is the electrical potential difference across the resting membrane

  4. A neuron is polarised only when the outer surface of axonal membrane possesses a negative charge and inner surface is positively charged

  5. Ionic gradients are maintained by Na-K pumps across the resting membrane which transports 3 N$a^+$ ions outwards for 2$K^+$ ions into the cell


Correct Option: D

Nerve impluse transmission at neuromuscular junction requires

  1. Ca

  2. Fe

  3. Cl

  4. Mg


Correct Option: A

Depolarisation of nerve membrane takes place through influx of .. ions

  1. Calcium

  2. Potassium

  3. Sodium

  4. Magnesium


Correct Option: C


In the resting state, the axonal membrane is (i)_ with more (ii) charged ions outside than inside. This unequal distribution of ions is due to (1) the selective permeability of the membrane, which forms an almost impenetrable barrier to (iii) and (2) the action of the _(iv), which pumps (v) Na$^+$ out of the neuron for every _(vi) K$^+$ brought in.
Select the option that correctly fills the blanks in the paragraph.

  1. (i) - depolarised, (ii) - positively, (iii) - Na$^+$, (iv) - sodium - potassium pump, (v) - three, (vi) - two

  2. (i) - depolarised, (ii) - negatively, (iii) - Na$^+$, (iv) - sodium - potassium pump, (v) - three, (vi) - two

  3. (i) - polarised, (ii) - negatively, (iii) - Na$^+$, (iv) - sodium - potassium pump, (v) - three, (vi) - two

  4. (i) - polarised, (ii) - positively, (iii) - Na$^+$, (iv) - sodium - potassium pump, (v) - three, (vi) - two


Correct Option: D
Explanation:

In the resting state, the axonal membrane is polarised with more positively charged ions outside than inside, unequal distribution of ions is due to the selective permeability of the membrane, which forms impermeable barrier to sodium ion and the action of the sodium which pumps three sodium ions out of the neuron for every two potassium ions brought in.

Thus, the correct option is '(i) - polarised, (ii) - positively, (iii) - Na$^+$, (iv) - sodium - potassium pump, (v) - three, (vi) - two.'

Sodium potassium pump transports

  1. Na+ and K+ out of the neuron

  2. Na+ and K+ into the neuron

  3. Na+ into the neuron and K+ out of the neuron

  4. K+ into the neuron and Na+ out of the neuron


Correct Option: D

Diencephalon is the centre for the following except

  1. Sweating

  2. Sneezing

  3. Thirst

  4. Hunger


Correct Option: B

A typical value of resting membrane potential is ______________.

  1. $-100$mV

  2. $-70$mV

  3. $-40$mV

  4. $-60$mV


Correct Option: B
Explanation:

The electrical potential difference across the resting plasma membrane is called as the resting potential. Its value is $-70$ mV.

A touch on the right hand stimulates neurons in the

  1. Left somatic sensory area

  2. Left occipital lobe

  3. Right somatic sensory area

  4. Right occipital lobe


Correct Option: A

The release of chemical messenger from synaptic vesicles is under the influence of which of these ion(s)?

  1. Cl-

  2. Fe++ and s++

  3. Ca ++

  4. Mg++ and Sr++


Correct Option: C