Answer:
In normal conditions, introns serve following functions in the body of an organism:
1) They contain genes of miRNA which are known as Mirtrons, reverse transcriptase, endonucleases, transposase etc.
2) It is because of presence of introns that alternative splicing of mRNA is possible. The sex determination in drosophila is based on alternative splicing.
Apart from this, alternative splicing can be useful and beneficial in an unforeseen situation such as an environmental problem which is faced by the organism for the first time.
Explanation:
Alternative splicing is an important mechanism because with the help of alternative splicing different type of proteins can be synthesized from the same pre mRNA transcript. In case suddenly the surrounding environment of an organism is changed and the environmental conditions have become extremely harsh due to which organism's life is at stake, in such situation organism may make a different type of protein through alternative splicing which can help the organism in survival.
Default splicing in Drosophila leads to the development of male off-spring while female off-spring is produced as a result of alternative splicing.
I think it'd be B.. I might be wrong tho..
<span>Studying the changes in densities of pocket gophers when large herbivores such as elk are excluded from mountain forests would be an example of studying ecology at the community level.
A community refers to a group of organisms of various species that live in the same location and interact with each other. So, if this scientist is observing gophers and elks, they are looking at the level of communities, not anything more or less.
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Explanation:
Looking at the Ecological concept of Modern Ecology
we have
Atmosphere, Lithosphere, Biosphere, Niche, Environment, Habitat, Population, Ecosystem and Biotic community
Hydrosphere and Geosphere are not part
so Atmosphere is the correct answer