Question

33) Reductive dechlorination is a process in which

A) the number of chlorine atoms present is reduced by oxygenase enzymes.
B) chlorinated organics are used as terminal electron acceptors in anaerobic respiration.
C) carbon dioxide is the final end product.
D) xenobiotics are cometabolized with other reductive reactions.

Answer 1

Reductive dechlorination is the process where bacteria use chlorinated organic compounds as terminal electron acceptors in anaerobic respiration, facilitating the removal of chlorine atoms from the compounds.

Step-by-step explanation:

Reductive dechlorination is a biological process, particularly seen in anaerobic conditions, where chlorinated organic compounds are reduced to release chlorine atoms. This process involves microbial action where certain bacteria use chlorinated compounds as electron acceptors instead of oxygen. The result is that chlorine atoms are removed (reduced) from the molecule. The correct answer to the question is 'B) chlorinated organics are used as terminal electron acceptors in anaerobic respiration.'

This process is significant in the environmental context as it leads to the breakdown of harmful chlorinated environmental pollutants. Organisms that can perform this type of anaerobic respiration might include various species of bacteria and Archaea, such as methanogens, which thrive in environments devoid of oxygen and can use substances like carbon dioxide as an electron acceptor to produce methane.