The theory of evolution proposed that a series of catastrophes or mass extinctions followed by repopulation could explain why species change over time
The mutagens that result in cancer damage DNA by (b) weakening the DNA strand or interfering with base pairing. This mutagens are called carcinogens, if they cause a damage to <span>a gene that makes a </span>DNA<span> repair protein, it means that a cell will have less ability to repair itself, and ,as a result, this will lead to formation of cancer.</span>
Answer:
they are Na+, K+ and Ca2+ ion channels.
Explanation:
Ionotropic acetylcholine receptors are also called nicotinic acetylcholine receptors because beside acetylcholine (Ch) they respond to nicotine. These receptors are primary receptors in muscle for motor nerve-muscle communication that controls muscle contraction.
Two molecules of ACh are required for receptor to open. Since the receptors are linked to ion channels, the channels open. Opening of the channel allows positively charged ions to move across it: sodium enters the cell and potassium exits.
The atomic number of an element is the same as the number of protons in the nucleus of an atom
