Question 13 Marks
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.
Answer
View full question & answer→| Plant | No. of chromosomes (2n) | Animal | No. of chromosomes (2n) |
| Black mulberry | 308 | Mouse | 40 |
| Rattlesnake fern | 184 | Humans | 46 |
| Pineapple | 50 | Gorilla | 48 |
| Oat | 42 | Elephant | 56 |
| Mango | 40 | Goat | 60 |
- Mango (40) and rattlesnake fern (184) show that size of organism has nothing to do with number of chromosomes.
- Gestation period in elephant is much longer than that in goat. Goat has a larger number of chromosomes than elephant. This shows that an organism with fewer number of chromosomes need not reproduce more easily than organisms with more number of chromosomes.
- Chromosomes are composed of DNA. Hence, it can be said that more the number of chromosomes/ cells greater is the DNA content.