Answer:
Stay safe from predators in their natural environments. I'm pretty sure this is the answer but it might not be.
Explanation:
Pesticide use can be very harmful beacause too much of them can cause the crops to go bad, and kill bees which help spread pollen and enhance the crops.
Answer:
B) Nitrogen-fixing bacteria and lightning
Explanation:
Nitrogen cycle is the natural process in which atmospheric nitrogen is converted into nitrite and nitrate with the help of bacteria.
Nitrogen cycle is directly dependent on nitrogen-fixing bacteria and lightning.
As bacteria are responsible for most of the chemical conversion in the nitrogen cycle such as nitrogen fixation (first step) is done by soil bacteria (Cyanobacteria) that form ammonia, which is toxic to plants; nitrification in which ammonia is converted into nitrites and nitrates with the help of Nitrobacter and denitrification bacteria involve Pseudomonas, and Achromobacter which convert nitrite and nitrate into nitrogen.
The lightning breaks nitrogen molecules and allow it to combine with oxygen in atmosphere which further dissolve in rain and form nitrates.
Hence, the nitrogen cycle is most directly dependent upon nitrogen-fixing bacteria and lightning and the correct option is B.
Answer:
Smaller populations have a greater chance of having one allele expressed disproportionately.
Explanation:
Genetic drift corresponds to a drastic casual alteration of the natural order, reaching the genotypic concentration of one or several species, not preliminarily involving natural selection factors, but caused by sudden events. Such phenomenon is characterized by the occurrence of ecological catastrophes, for example: earthquakes, tsunamis, tornadoes, floods, burnings, avalanches and other processes, affecting a large population contingent. Thus limiting the genetic content of a particular group, restricted to the prevailing individuals.
In this situation, with low variability, differentiated individuals will experience a more significant selection pressure in relation to the ascending lineage, which minimized the achievements of selection due to the high number of living individuals. In this scenario, smaller populations will have a greater chance of having a disproportionately expressed allele as the number of members is reduced. We can also see this effect if by using a coin we imagine that heads and tails are two alleles in a population and each coin toss represents one member of that population.
