 |
1 | |
The increase in number of ClB daughters that could not produce sons was due to the fact that X rays caused mutations |
| | A) | In the somatic cells of the ClB daughters |
| | B) | In the germ cells of the ClB daughters |
| | C) | In the somatic cells of the fathers of the ClB daughters |
| | D) | In the germ cells of the fathers of the ClB daughters |
|
|
2 | |
The female flies that could not produce living sons |
| | A) | Carried one recessive, lethal, X-linked mutation |
| | B) | Carried two recessive, lethal, X-linked mutations |
| | C) | Carried one recessive, lethal, autosomal mutation |
| | D) | Carried two recessive, lethal, autosomal mutations |
|
|
3 | |
According to the data, in approximately 90 cases, X rays caused |
| | A) | A recessive, lethal, X-linked mutation |
| | B) | A dominant, lethal, X-linked mutation |
| | C) | A recessive, lethal, autosomal mutation |
| | D) | A dominant, lethal, autosomal mutation |
|
|
4 | |
If the dosage of X-rays was decreased by 50%, we would expect |
| | A) | More ClB daughters that would be unable to produce sons |
| | B) | Fewer ClB daughters that would be unable to produce sons |
| | C) | Fewer ClB daughter that would survive |
| | D) | The same results |
|
|
5 | |
As described in Chapter 8, inversion heterozygotes produce strange chromosomes if a crossover occurs in the inverted region. The gametes produced from such a crossover usually produce offspring that cannot survive. (Refer back to pericentric and paracentric inversions). The inversion on the ClB chromosome thereby prevents the formation of viable offspring if a crossover occurs in the region that contains the lethal allele. Consider what would happen if this inversion were not present and a crossover occurred in the region between the lethal allele on the lB chromosome and the lethal allele caused by X rays on the homologous X chromosome. If such a crossover occurred, what would be the results? |
| | A) | Half of the male offspring would survive. |
| | B) | All of the male offspring would die. |
| | C) | All of the female offspring would die. |
| | D) | Half of the female offspring would die. |
|