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Question
From the internet, gather information about the chromosome numbers of five animals and five plants. Correlate the number with the size of organism and answer the following questions.
- Do larger organisms have more number of chromosomes/cells?
- Can organism with fewer chromosomes reproduce more easily than organisms with more number of chromosomes?
- More the number of chromosomes/cells greater is the DNA content. Justify.
Solution
Chromosome number of animals
| Animal | Chromosome Number | |
| 1. | Rat | 21 |
| 2. | Elephant | 56 |
| 3. | Giraffe | 30 |
| 4. | Cat | 38 |
| 5. | Horse | 64 |
Chromosome number of plants
| Plants | Chromosome Number | |
| 1. | Maize | 20 |
| 2. | Onion | 16 |
| 3. | Rice | 12 |
| 4. | Wheat | 42 |
| 5. | Mango | 40 |
- There is no correlation between the size of an organisms with the number of chromosomes present in the cells of its body. So, larger organisms do not have more number of chromosomes per cell.
- Process of reproduction follows a common pattern and is not dependent on the number of chromosomes in an organism. So, the organisms with fewer number of chromosomes need not reproduce more easily than the organisms with more number of chromosomes.
- Each chromosome is made up of DNA and protein. So, if a cell has more number of chromosomes, it will possess the greater DNA content.
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