EVERYDAY SCIENCE

Detailed explanation-1: -In contrast to obligate anaerobes, facultative anaerobes (e.g., E. coli) grow most rapidly when respiring oxygen and switch to anaerobic respiration in the absence of oxygen or to fermentation in the absence of alternative electron acceptors (17).

Detailed explanation-2: -It can grow with or without oxygen. coli grows anaerobically (in the absence of oxygen). However, unlike some anaerobic bacteriaE. coli also grows well in aerobic environments, such as a culture flask in a laboratory.

Detailed explanation-3: -E. coli is a metabolically versatile bacterium that is able to grow under aerobic and anaerobic conditions. Adaptation to environ-ments with different O2 concentrations, which is vital for E. coli competitiveness and growth, requires reprogramming of gene ex-pression and cell metabolism.

Detailed explanation-4: -Thus, the correct answer is ‘It is diploid.