Q. A scientist added a chemical (cyanide) to an animal cell to stop aerobic respiration. Which of the following is most likely to have been affected by this treatment?
A) Active transport of substances across the plasma membrane
B) Passive transport of substances across the plasma membrane
C) Diffusion of substances across the plasma membrane
D) The thickness of the plasma membrane
Explanation
Cyanide reacts with one of the proteins (cytochrome-$a_{3}$) in the electron transport system and prevents transfer of electron to oxygen. It leads to checking the ATP formation through oxidative phosphorylation. ATP is required for active transport of substances across the plasma membrane, besides some other metabolic reactions.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.