An amino acids between the two species, there are twenty positions along the sixty amino acids sequence that are identical between the aphid and the bacterium Pantoea. A computer can be used to compare these quences from the rest of the species to the aphid sequence.
Answer:
Telomerase
Explanation:
Repetitive regions at the ends of Chromosomes are known as telomeres and these are crucial for chromosomal stability. There is no gene present and they provide protection to internal parts of chromosome. The telomeres are eaten up slowly by ‘DNA REPAIR MECHANISM’ after many division cycles, which is considered as ageing. That why, a cell can divide only certain number of times.
Some cells have ability to express an enzyme telomerase that maintain the length of telomere. The telomerase enzyme contributes to cell immortality by rebuilding the damaged telomere. Thus telomerase enzyme is necessary for cancer initiation and survival of tumor. Telomerase enzyme can make its own DNA by using its RNA as template
. It extends the overhang strands of DNA by using a comlementary DNA.
Answer:
Explanation: New experimental data can lead to a better understanding of theories or can even disprove them.
The answer is that they have traits that enabled them to survive in a changing environment.
During the evolution of the Earth, and later during the evolution of life, the environment was not constant. Change in the environment could lead to an extinction of some species. But, some species were able to adapt or could tolerate a wide range of environmental factors. One of the explanation, why unicellular organisms did not evolve into complex multicellular organisms is because they have traits that help them to tolerate the wide range of factors, and thus, survive in changing environment.
