Answer:
a. adenine and guanine
Explanation:
A purines nucleotide is a combination of the heterocyclic aromatic rings, the imidazole and pyrimidine ring.
The answer is chlorophyll b I believe. <span />
Answer:
When change occurs in the population of one species affect the entire ecosystem. If the population of herbivores goes very high then all the producers i. e. Plants are eaten by the herbivores and no vegetation is available for other animals and they will die because of hunger.
For example, if the population of deer increases in a forest ecosystem, so all plants are eaten by the deer and no plants are available for another herbivores.
Operons are gene regulatory mechanisms that involve promoting and repressing genes that are involved in the metabolism of organic substances (i.e. sugars). Living organisms have the innate ability to metabolize glucose as the main source of energy. Although, in the absence of glucose, the organism must "learn" to use sugars other than glucose (such as lactose) in order to survive.
For instance, in the <em>lac </em>operon:
In the absence of glucose, various regulatory proteins promote the transcription of the gene related to the metabolism of lactose. This will ultimately lead to the production of the enzyme beta lactosidase which will enable the organism to use lactose as energy in the absence of glucose. This will therefore increase the chances of the organism for survival and will be naturally selected for evolution.
Answer:
co- evolution is the correct answer of given statement
