Ans.
HD (Huntington's disease) is a genetic neurological disorder that occurs due to damage and death of brain cells. it is caused by an autosomal dominant mutation in HTT (huntingtin) gene, having a trinucleotide repeat section that makes HTT protein.
The mutation leads to an increase in this nucleotide repeat count, associated with formation of altered or mutated huntingtin protein. These altered proteins show deleterious affect on brain cells and result in Huntington's disease.
Thus, the correct answer is 'option A). a mutated gene.'
<span>Almost. Due to the fact that they will be different at the DNA level.</span>
Answer: crossing over allows for genetic variation
Explanation:
crossing over is the exchange of genes between two chromosomes which ends up resulting in non-identical chromatids that comprise the genetic material of gametes (sperm and eggs).
Basically crossing over makes the chromatids that are held together by a centromere, no longer identical to eachother which creates genetic variation.
