Answer:
The modern medical era began when an absent-minded British scientist named Alexander Fleming returned from vacation to find that one of the petri dishes he forgot to put away was covered in a bacteria-killing mold. He had discovered penicillin, the world's first antibiotic.
It is A both chemical changes and flow of energy
4. Which of the following methods of soil conservation uses the roots of plants as anchors in the soil?
<span>Planting trees on sloped surfaces.
In this way, soil erosion is minimized as well as the amount of water run off.
5. </span><span>Which of the following soil components results from the breakdown of parent material?
</span><span>Minerals</span>
<span>At the end of meiosis II, compared to the DNA from the original cell, the DNA in each of the four new cells is C)half as much and genetically different from the original. Meiosis is the type of cell division in which the genetic material is reduced by half. Thus, choices B and D are incorrect. Further, the exchange of genetic material between homologous chromosomes so-called the crossover occurs during meiosis, so DNA in new cells will be genetically different from the original DNA. Thus, the correct choice is C.</span>