To determine which conclusion BEST describes the data in the table regarding the distribution of bases (G, A, C, T) in different types of organisms, let's analyze the information provided.
The table displays the following proportions of DNA bases for Mold, Plant, Reptile, and Mammal:
| Organism | G | A | C | T |
|----------|----|----|----|----|
| Mold | 15.2 | 34.0 | 14.9 | 35.1 |
| Plant | 19.7 | 41.2 | 19.5 | 42.1 |
| Reptile | 12.9 | 35.6 | 13.2 | 35.7 |
| Mammal | 14.6 | 39.5 | 13.8 | 37.6 |
Let’s evaluate the provided conclusions:
1. Organisms have different proportions of bases in their DNA.
- When we look at the proportions of G, A, C, and T, we can see that they vary for each organism. For example:
- Mold has 15.2% G, 34.0% A, 14.9% C, and 35.1% T.
- Plant has 19.7% G, 41.2% A, 19.5% C, and 42.1% T.
- Reptile has 12.9% G, 35.6% A, 13.2% C, and 35.7% T.
- Mammal has 14.6% G, 39.5% A, 13.8% C, and 37.6% T.
- These values clearly demonstrate variability, supporting the conclusion that organisms have different proportions of bases in their DNA.
2. The genetic code is exactly the same among all living organisms.
- While the fundamental structure of DNA and genetic code is the same for all living organisms (using the same bases A, T, C, and G), the proportions of these bases are different among the organisms listed. The data does not support this statement because the given proportions vary.
3. Animals have similar amounts of bases in their cells.
- From the data, even among animals listed (Reptile and Mammal), the proportions are not identical. For example:
- Reptile has 12.9% G and Mammal has 14.6% G.
- Reptile has 13.2% C and Mammal has 13.8% C.
- The differences in values suggest that even among animals, base proportions are not exactly the same, making this conclusion less accurate.
4. Plants are least related genetically to other organisms on this table.
- The table provides information only about the proportions of DNA bases and does not offer direct evidence about genetic relationships. Although the proportions for plants are distinctive, this does not necessarily mean that they are the least related genetically to other organisms compared to others on the table. Hence, this is not the best possible conclusion from the data provided.
Considering these analyses, the conclusion that BEST describes the data in the table is:
Organisms have different proportions of bases in their DNA.
