Cytochrome iv allow the transfer of electron from cytochrome a₃ present in cytochrome iv that reduce oxygen on mitochondrial membrane for ATP synthesis.
Hypothesis:cyanide blocks the cytochrome iv, therefore, oxygen will not be utilized which is important to derive energy for the cell to live.
So binding of cyanide inhibit the electron transfer to the oxygen atom, therefore, the electron transport chain will be blocked at the terminal position. This blockage does not allow the use of oxygen atom to derive energy for the cell and result in the rapid death of the cell.
So cyanide poisoning in humans is fatal because it blocks ETC by restricting the transfer of electron from cyt iv to oxygen and ultimately blocks ATP synthesis which is required by the cell to live.
Answer: The correct answer is silent mutation . In this type of mutation there is no change in the phenotype of the individual which means there occurs a mutation where two different amino acid codes for the same protein .There are sequences present in the body where a point mutation occurs but the protein formed is still the same .If you will see the genotype you can easily observe that the amino acid sequence is different but the protein formed is same. Example AAA codes for lysine and the amino acid lysine is formed by AAG .
