Answer:
A. the two genes on chromosome 1 are more than 50 mu apart.
Explanation:
Two or more genes present on the same chromosomes are the linked genes. Linked genes do not assort independently and do not exhibit crossing over. Therefore, the linkage of genes results in deviations from Mendel's law of independent assortment. However, if the linked genes are present far from each other on the same chromosome, they may exhibit crossing over.
The greater the distance between the linked genes, the higher are the chances of crossing over. Crossing over of linked genes would result in some of the progeny to have the new gene combinations as it occurs during an independent assortment of two genes. Therefore, Mendel observed an independent assortment of two genes present together on chromosome 1 since they were present far apart from each other (more than 50 mu apart).
It's called complete dominance of the dominant gene when it totally masks expression by the recessive gene.
A vertebrate-animal embryo gives rise to the centrum. The centrum is a bone that is part of the vertebral column. It is the hollow space within the vertebra that protects and contains the spinal cord. Within this hollow area are several nerves that send impulses to the brain enabling the organism to function and be at its homeostasis.
