Answer:
Purple, spherical-shaped organisms arranged in chain like formations.
Explanation:
Bacteria are the microscopic organisms and included in the prokaryotes as they do not have nucleus. Two main types of bacteria are gram positive bacteria and gram negative bacteria.
The gram positive bacteria has thick cell wall peptidoglycan cell layer and can uptake the crystal voilet stain. These bacteria seems purple under the microscope due to the uptake of stain. The bacteria Streptococcus pyogenes are spherical in shape and occurs in the cluster of chain.
Thus, the correct answer is option (d).
Directional selection is where one phenotype is favored, so an example would be "a population of madagascar hissing cockroaches suffers heavy predation from lizards. Because their heads are small, the lizards are unable to eat the very largest adult cockroaches, and instead prey upon small and medium sized adults, so as a result the large cockroaches are favored and live".
Meanwhile, disruptive selection is where both extreme phenotypes are favored, an example would be "a population of rabbits can have black fur, white fur or grey fur. This population of rabbits lives in an area of white rocks. When a local volcano erupts, black volcanic rock now dots the landscape amongst the white rocks. Now the black and white rabbits live longer because the black and white spots on the landscape camoflauge them. The two extreme phenotypes are being favored."
Answer:
D, C and A are the correct options.
B is less likely rather is a personal reference.
