<u>Answer</u>: C) Directional selection occurs when one of two extreme phenotypes is selected for.
The type of natural selection known as directional selection is defined in population genetics in the case in which an extreme phenotype is favored over other phenotype. Thus, the population and its allele frequency will evolve towards this end of the trait spectrum (extreme phenotype). This is also the case illustrated in the graph where the right side represents the extreme phenotype.
The best option is D. Based on scientific evidence about algal bloom, it would be best to evacuate all humans from the area around the lake. Algal bloom is caused by excess nutrients in the lake. This occurrence is linked to the death of fishes, plants, mammals and birds. Also. it has been said to cause human illnesses. Thus, to avoid this, it would be best to stay away from the lake with algal bloom.
<u>Answer</u>: Option D. RNA polymerase.
<u>Explanation</u>:
- Transcription is the process which is used to produce RNA from a DNA template.
- The enzyme involved in the process of transcription is <em>RNA</em> <em>polymerase</em> which is responsible for separating the DNA strands and making an RNA which is complementary to the DNA.
- RNA polymerase joins the nucleotides in the newly formed RNA strands by utilizing the energy released from the cleavage of the additional phosphate bonds that are removed by it.
- The RNA polymerase dissociates from the DNA only after the process of transcription is complete.
Attached is an image with the correct labeling.
Meiosis occurs in a series of different phases and creates genetically unique reproductive cells. The process which helps make meiotic cells genetically different and occurs during prophase I, but not during prophase II, is crossing over (C). Crossing over is the exchange of genetic material between two homogenous chromosomes. It is one of the final phases of prophase I. This process is called synapsis. It occurs when the matching regions on the matching chromosomes break and then reconnect to the other chromosome