The nucleus during mitosis. Micrographs illustrating the progressive stages of mitosis in a plant cell. During prophase, the chromosomes condense, the nucleolus disappears, and the nuclear envelope breaks down.
Answer: a. the lowest trophic level
Explanation:
The keystone species is the one on which the entire ecosystem depends upon. It maintains a balance in the ecosystem. If this species is removed the ecosystem will drastically change. The members of the keystone species are abundantly available at the lowest trophic level. This will help in making a balance in a community or ecosystem. If some members die others will be available to survive others.
Plastic is abiotic because it is non-living
Answer:
The correct answer is option d) "Silencer".
Explanation:
Gene silencing is the regulation of a gene expression that results in avoiding the expression of a gene during a certain period of time. A silencer is a DNA sequence that produces gene silencing. In this example the researcher founds that a gene is not longer regulated in all cells and the gene is still transcribed and translated into protein. The mutation responsible of this it is likely to be occurring in a silencer, avoiding gene silencing of the studied gene in all cells.
