In hexaploid wheat, the haploid (n) ar basic (x) numbers of chromosomes are:
1. n=7 and x=21
2. n=21 and x=21
3. n=21 and x=14
4. n=21 and x=7
Cri-du-chat syndrome in humans is caused by the:
1. | fertilization of an XX egg by a normal y-bearing sperm |
2. | loss of half of the short arm of chromosome 5 |
3. | loss of half of the long arm of chromosome 5 |
4. | trisomy of 21st chromosome |