The correct answer of the given question above would be the third option: THE EVOLUTION OF POPULATIONS OVER TIME. What is represented by the base of a phylogenic tree is the evolution of populations over time. It is also known as the evolutionary tree. This tree shows the evolutionary relationships among species.
Answer:
A considerable increase in phytoplankton populations in winter, and a greater increase in spring due to increase in light intensity.
Explanation:
Nitrogen and phosphorus are important nutrients required by phytoplankton populations. The growth of phytoplankton populations is dependent on the level of the availability of Nitrogen and Phosphorus in the presence of sunlight.
A rise in the aquatic coastal levels of nitrogen and phosphorus would result in a great increase in phytoplankton populations in spring, as stimulated by nutrient enrichment coupled with the availability of sunlight during spring. Phytoplankton populations would increase also in winter but not as high when compared to the rise in population in spring
Answer:
This is through the process of methylation and phosphorylation of histones tails.
Explanation:
The addition of a methyl group to the amino acid of the histones of the nucleosomes that compacted DNA in the nucleus is called mehtylation, while the addtion of phodpahte is phosphorylation
Its effects on gene expression depends on the number of <u> methyl groups, and type of amino acid that methylated. During transcription. </u>
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The DNA double strands are compacted and therefore hidden from transcription factors and enzymes of transcription by the hitones tails of the neuclosomes, Methylation weaken the binding bonds between the tails and DNA structure ; thereby aiding the uncoiling of DNA from the tails.(nucleosomes).This chemical reaction aided DNA strands exposure to transcription factors and enzymes, for initiation of transcription. This explains the dyanmic activity of methylation
Futhermore phophorylation also favours unwrapping of DNA, by imitating modifying enzymes e.g H3Y41E and H3T45E and convert it to→→ H3Y41phopspahte to aid DNA unwrapping and accessibility to transcription factors and RNA polymerase Enzymes,