Question

In presence of cyanide, azide and carbon monoxide the rate of respiration
A. Decreases
B. Increases
C. Remains the same
D. None of the above

Answer 1

Hint:- These deadly chemicals, cyanides, azides, and carbon monoxide, whose basic low concentration is very effective in killing a human. All these compounds are inhibitors of the irreversible enzyme.

Complete solution: Cyanide practically forbids the occurrence of the electron transport chain. In cellular respiration, this critical process contributes to a loss of ATP production and shuts down the cell, leading to cell death. As azide and carbon monoxide are more inhibitory compounds, cellular respiration that leads to cell death is prohibited as they can replace oxygen from their carrier. Owing to the reduction in the supply of oxygen, this contributes to a drop in the respiratory rate. Thus, in the presence of these chemicals, cellular respiration decreases to a great degree that would definitely lead to the death of the affected person if not looked at very quickly.

Hence, Option A is the right answer.

Additional Information:
Azide and cyanide, in vivo as well as in vitro, inhibit both respiration and photosynthesis. The mechanism of inhibition of photosynthesis is controversial, although inhibition of respiration is accounted for by inhibition of metal-containing terminal oxidases, mainly cyt oxidase. Cyanide is well known, neither photosynthetic electron transport from ${H_2}O$ to NADP or to artificial electron acceptors nor photosynthetic phosphorylation are inhibited by azide and photosynthetic electron transport (1,2). The inhibition of photosynthesis by these poisons must therefore be explained by an indirect mechanism which invokes the inhibition of one or more photosynthetic carbon cycle steps.

Note:-
The exchange of gases and chemical reactions that take place during respiration does not take place in the absence of active enzymes and thus affects the breathing process.