Final answer:
Microaerophiles are bacteria that can process oxygen but in lesser amounts. They prefer environments with lower levels of oxygen and may contain less SOD + catalase or peroxidase. Bacteria that are capnophiles have a higher requirement for carbon dioxide and can also fall into this category.
Step-by-step explanation:
Bacteria that can process oxygen but in lesser amounts are called microaerophiles. These bacteria prefer environments with lower levels of oxygen than normal atmospheric conditions. They can still make ATP by aerobic respiration and may also ferment sugars aerobically.
Microaerophiles have requirements for increased levels of carbon dioxide in the atmosphere and may contain less SOD + catalase or peroxidase. These enzymes are involved in the detoxification of reactive oxygen species. Bacteria that are capnophiles, or organisms that require a higher than atmospheric concentration of CO2 to grow, can fall into this category.
Unlike strict anaerobes, which cannot tolerate oxygen at all, microaerophiles can tolerate oxygen but in lesser amounts. They have some cellular defenses against oxidative stress but in smaller quantities compared to organisms that perform aerobic respiration and produce more reactive oxygen species.