The statement 2+2=4 would be considered a LAW in the science world
Dragonflies are most closely related to damselflies. Damselflies are smaller, slimmer, and most of them fold their wings along their body when they are resting.
Answer:
An asteroid impact.
Explanation:
An asteroid impact is considered to have tossed rubble across the earth, killing off many species of plants and animals, 65 million years ago. Volcanic activity is involved in at least four mass extinctions, whereas an asteroid in just one.
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.'
