The action potential spreads through an axon by depolarizing adjacent membrane to threshold.
- K+ departs the cell after Na+, which enters the cell first. Ions can move freely across the axon membrane because of the difference during the action potential.
- Because sodium contains a positive charge, the neuron becomes more positive and depolarized. Potassium channels take longer to open. As soon as the cell does open, K+ rushes out, reversing the depolarization known as repolarization.
- Sodium channels close during the peak of the action potential when potassium leaves the cell. When potassium ions are effluxed, the membrane potential is lowered or the cell becomes hyperpolarized.
- Outside of the cell, the concentration of Na+ is greater than inside the cell. while the concentration of K+ is is greater inside the cell than outside.
learn more about action potential here: brainly.com/question/6705448
#SPJ4
Answer:
The question is incomplete.
However, I notice that your question is mainly dealing with
"Nucleotides with a single ring structure"
I tackled that part, also providing explanation to the point you focused on.
Explanation:
Nucleotides are compounds in which nitrogenous bases (purines and pyrimidines) are conjugated to the pentose sugars (ribose or deoxyribose) and at least one phosphate group. Thus a nucleotide consists of a nitrogenous base, pentose sugar and at least one phosphate group.
Examples of the nitrogenous bases are Adenine, Guanine, Thymine, Uracil and Cytosine. Of all, Thymine, Uracil and Cytosine are with single ring, while Adenine and Guanine are double ring structure.
I think the answers are b,d,and e
Because back then before pangaea occured the oceans we see today where all one before now they are seperated hope this helps.