Answer: B
Explanation: Traits usually die off when they are unneeded by the organism, or if the trait causes harm to the organism's survival. Through natural selection, over time, the organisms with the best combination of traits for its survival will become the dominating species, and those with weaker traits may not survive long enough to pass off their traits to future offspring.
In eukaryotes, the DNA strands are linear, and DNA polymerase can't replicate the very ends of the DNA strands! These ends are "protected" by repeated sequences called "telomeres." Either the chromosome gets shorter with each replication, or else a special enzyme-nucleic acid complex called telomerase adds new telomeres to the ends. A prokaryotic chromosome is circular and thus does not have the problem of having ended.
<span>Eukaryotic DNA is wound around histones, coiled, and supercoiled -- to replicate it, there have to be unwinding mechanisms, and mechanisms to reduce the degree of coiling. In prokaryotes, the winding problem is much less, and there aren't any histones.</span>
Answer:
Helium
Explanation:
Helium is extracted in a few places in the world, namely USA, Algeria, Russia and Qatar. Helium is abundant in space, where it's produced as a product of the fusion reaction inside stars such as the sun.
plutoids hope this helps :)
Answer:
It would have to be passive immunity
Explanation:
Because active immunity develops after being exposed to the pathogen and its not acquired either because its similar to active and it isn't inborn because that comes from your parents