Answer:
16) 6 electrons
17) 6 protons
18) 6 neutrons
19) 4 electrons
20) 6
Explanation:
There are 6 electrons on the rings in total and 6 protons inside the nucleus. If you count the black cir les, there are 6 of them so there are 6 neutrons. Knowing that the inner ring can only hold 2 electrons the most, 6-2= 4. So there are 4 electrons on the outer ring. Knowing that you can get the atomic number based on the number of protons an atom have, the at pool mic number would be 6.
Native Americans and Type O Blood
Modern Native Americans have very high frequencies of Type O blood.
In some places in North and South America, the frequency is as high as 100%. Anthropologists believe that early Native Americans arrived in North America by crossing over the Bering Land Bridge around 15,000 years ago, from East Asia.
Modern East Asian populations, with whom modern Native Americans share ancestry, do not have high frequencies of Type O blood. Instead, they have some of the lowest frequencies of Type O blood in the world.
B. Sickle-Cell Anemia
As many as 20-30% of people living in equatorial Africa have at least one allele on Chromosome 11 that codes for sickle-cell anemia (they have an, "S" rather than an, "A" allele). This is odd because usually, 80% of people who have two S alleles die before they can reproduce,
For each of the following cases:
1. What forces of evolution are at work? State all that apply.
Mutation
Natural Selection
Genetic Drift
Gene Flow.
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it is caused by relaxation of smooth muscle cells that are in the vessel walls which in the large arteries.
