Answer: Missense mutation
Explanation:
Missense mutation is a type of point mutation where a single nucleotide is changed to cause substitution of a different amino acid. This in turns render the resulting protein non-functional.
In the case of sickle-cell disease, the sixth amino acid in the gene sequence, glutamate (GAG) is substituted with valine (GUA), due to Adenine nucleotide changed to Uracil nucleotide. Thus, missense mutation has occurred
Answer:
James Watson and Francis Crick were mainly the first to build a model of a DNA structure. (Your welcome).
Explanation:
This is because the traits like height, are influenced by environmental conditions around the individual. For example, there are two children born to same mother. But one is given best facilities, nutrition and care, whereas other one is brought up by a poor family, which hardly get good food to eat. His condition is much worse than the first case. In such a situation, the former child will grow up healthy and fit, and will have more height than the later one. Although, both got genes from same parent, but the environmental conditions influenced the expression of those genes differently.
