Answer & Explanation:
a) a) Mutualistic relationship differs from parasitism because the first one benefits both of the involved organisms. Otherwise, parasitism benefits only one of the organisms and it can harm the host. Therefore, the parasite would have to be smaller than the host and it would be somehow extracting energy from the host.
b) The direction of evolutionary changes would follow some kind of pattern, like coevolution. Therefore, analyzing the phylogenies individually and then contrasting them, would help to understand how the host, as well as the parasite, have been evolving.
c) The phylogeny would also help to understand what changed first, or if they changed together as a result of coevolution.
The correct answer is:
A. Photosynthetic pigments absorb energy from light.

Oxygen is required for aerobic respiration. This reaction produces ATP (universal currency for energy) which our bodies use to survive. Without oxygen much less ATP is produced, as aerobic respiration cannot occur in the lack of oxygen. ATP can be formed by anaerobic respiration, in the lack of oxygen, but this produces far far fewer molecules of ATP. This also produces lactic acid causing us to become fatigued and tired. Thus oxygen is crucial to produce the maximum amount of ATP possible.
Glucose is the main molecule which is respired by our bodies to produce ATP/ energy, which our bodies use to survive. Oxygen and glucose react in the mitochondria to make ATP (release energy.) It therefore, is called a respiratory substrate.
Note: I'm avoided talking about the exact phases of respiration as it is usually not covered till college/ A level standards. If you would like to know exactly which reaction requires oxygen and how it's used (i.e. the stages of respiration) don't hesitate to ask.
Answer:
It is significantly easier to be infected with cutaneous anthrax as compared to other forms of anthrax.
Explanation:
LD50 is the lethal dose that can cause adverse effects and death. The LD50 of cutaneous anthrax is too low as compared to inhalation and gastrointestinal anthrax which means that only few Bacillus anthracis endospores can cause infection via cutaneous route while other routes require at least 200 times greater quantity to cause infection.
The geological conditions.