Answer:
it reacts easily with other substances. This is why they easily rust and oxidize when in contact with oxygen, and tarnish when meets water.
Because they would need to compete over resources.
Answer: The strongest jet streams are the polar jets. The Northern Hemisphere and the Southern Hemisphere each have a polar jet and a subtropical jet.
Explanation:
hope that helps
Answer:
1. They keep casts to preserve the real fossils.
2. Maybe someone would steal a fossil and sell it on the dark web?
3. They keep casts to keep the real fossils in prime condition, by that I mean like undamaged.
After hundreds or even thousands of generations both alleles for sickle cell anemia are still common in those of African ancestry. This is supported by two mechanisms: heterozygote advantage and gene flow.
Heterozygote advantage
When an allele is said to be heterozygous, it is carrying one copy of a gene. For example if one carries a copy of sickle cell allele, it will stay in the population even after many generations — natural selection will not be able to remove it and it will be passed on through generations. So, having one copy of that allele is advantageous but not deleterious.
Gene flow
With humans migrating throughout the different parts of the world, sickle cell allele is passed from one person to another or in different populations. It is actually advantageous to have one copy of this allele especially if there’s malaria in the area, which the allele is resistant.