Depolarization of neuronal plasma membrane
How is the depolarization of neuronal plasma membrane produced? How does the cell return to its initial rest?
Expert
Whenever the neuron obtains a stimulus by the binding of neurotransmitters to particular receptors sodium channels open and the permeability of plasma membrane in the postsynaptic area is modified. Sodium ions then go to the cell causing lowering (that is, less negative) of the membrane potential. Whenever this reduction of membrane potential reaches a level termed as the excitation threshold, or threshold potential, around –50 mV, the action potential is produced, that is, the depolarization intensifies until reaching its utmost level and the depolarization current is transmitted all along the remaining length of neuronal membrane.
When the excitation threshold is reached voltage-dependent sodium channels in membrane open permitting more sodium ions to enter the cell in the favor of concentration gradient and an around –35 mV level of positive polarization of the membrane is attained. The voltage-dependent sodium channels then close and additional voltage-dependent potassium channels open. Potassium ions then depart the cell in favor of concentration gradient and the potential difference of the membrane reduces, a process termed as repolarization.
The action potential triggers similar electrical phenomenon in neighboring areas of the plasma membrane and the impulse is therefore transmitted from the dendrites to terminal area of the axon.
Voice mail is strictly speaking, is a form of E-mail only. Here, a message, instead of being communicated in a written form, is sent in the voice of the caller. Like e-mail, it is very easy to use and is a convenient way of leaving short messages for someone who is not immediately available.
What do you mean by chicken embryo method?
Objectives of Planning Planning in any organization serves to realize the following objectives: 1 Reduc
Specify the evolutionary origin of internal membranous organelles of cell?
Why are most of the ammoniotelic beings aquatic animals?
Give a brief description of synthetic auxins and also write down their uses?
Q.1. Visit any organization/ company and prepare its short organizational profile. Then describe the internal and external communication process of the organization/ company you have visited along with a diagram. Q.2. Suppose there is an ad
Explain the term Spearheading Transformation in Health care organization ?
Explain Quality Fundamentals in brief ?
Following steps must be taken in resolving a conflict already arisen: 1) Preliminary step: this step involves knowing of full details of the conflict and the first thing to note is the stage of conflict. The more advance the stage of conflict, the more e
18,76,764
1931444 Asked
3,689
Active Tutors
1423434
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!