Answer:
Explanation:
they can not chose to adapt. adaptations occur over a very long period time(darwinism) Evolution is not selective in the sense that the organism being changed can choose.
The answer to the problem is c
The right answer is it can be attributed to similarities among organisms in proteins and nucleic acids (especially in their coding regions in their genome).
Genomes consist of coding regions, which correspond to genes, and non-coding regions. The coding part is the one that gives the proteins that are involved in the structure and metabolism of the individuals. if two individuals have a similar protein-giving genome, then they will probably have the same structure and metabolism.
Ribonucleic acid, the basic unit of RNA, has a hydroxyl (-OH) on the second carbon atom. On the other hand, the deoxyribonucleic acid, the basic unit of DNA, has a single hydrogen in the second carbon. This chemical structure difference makes RNA heavier than DNA due to the extra carbon atom.
The RNA/RNA-DNA hybrids can be separated from double-standard DNA using a high-resolution centrifuge due to this difference in weight. The image belows shows the extra oxygen atom in the 2' carbon
Answer:
C-14 can be used for dating fossils (50,000-70,000 years)
Explanation:
A fossil is a preserved remains of a once-living organism from a past geological age. Moreover, radioactive decay is a natural process by which an unstable atomic nucleus loses energy by emitting radiation. C-14 (Carbon 14) is a radioactive isotope of carbon that emits radiation which is widely used for dating fossils. C14 decays into the stable isotope C 12 and this radioactive isotope (C-14) has a half-life of 5730 yrs, thereby it is possible to use this rate of decay in order to calculate the age of an object according to the proportion of C14 remaining. The short half-life of C-14 indicates that this radioactive isotope cannot be used to date extremely old fossils (after 50,000-70,000 years, the C-14 dating method is no longer valuable for estimating the age).
