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.'
The right answer is <span>the light saturation point.
More light usually results in higher photosynthesis levels. However, with the increase of the intensity of the light, the photosynthesis rate eventually reaches a maximum point. This point is called "luminous saturation point".
When this point is reached, the intensity of the light does not increase the rate of photosynthesis and the rate of photosynthesis curve ceases to increase.
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The sun.
I hope this helped
