<span>Valence is defined as number of electrons that are present in the outermost orbital. Oxygen is in the 16th column of the periodic table and the total number of valance electrons is determined by units place digit of the column position which is 6 for oxygen. The outermost orbital is the high energy level and there are two in that orbit. So the valance is +2.</span>
Answer: C
Explanation:
If immigration and emigration numbers remain equal, decreased birthrate could cause a slowed growth rate
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Decreased birthrate always affects the numbers in terms of population.The less births there are, the smaller the number of people. Even if the death rate remains constant a decreased birthrate will slow growth of population.
Answer:
Yeah, so basically the image is showing restriction enzymes. The job of restriction enzymes is mainly involved in research when scientists use them for cloning human genes. But that's besides the point...
Main thing you have to understand is that restriction enzymes cut at very specific places along DNA sequences. If you look at the restriction enzyme Rsa 1, you can notice that it cuts only between a thymine nucleotide base and an adenine nucleotide base. Next, if ya look at Sty 1 (be careful b/c W can represent adenine or thymine), it cuts only between two directly adjacent cytosine nucleotide bases!
SO.... if we go to Rsa 1, we can find the answers by dividing up the sequences between the pattern we saw in the gray box. It only cuts between adenine and thymine bases. Based on that, we can find the number of fragments created, and the segment lengths (basically just like how many nucleotide bases are in each strand). Hope ya found this helpful!
The correct answer is microglia.
<span>Microglia is glial cells found in the central nervous system with the protective role. Because they are the resident macrophage cells, they act as the first and main form of active immune defense. Microglia is constantly cleaning the CNS for plaques, damaged or unnecessary neurons, and infectious agents, like viruses or other microorganisms.</span>
