Microorganisms which are killed in the presence of normal concentrations of atmospheric oxygen are called obligate anaerobes.Some species are capable of surviving in upto 8% while other losing viability in 0.5%.They survive without oxygen as they use other molecules as electron acceptor instead of oxygen.
Explanation:In aerobic organisms oxygen is used in cellular respiration as an electron acceptor.oxygen accepts electrons and turns into water H2O or CO2.While obligate anaerobes other molecules as their primary electron acceptors.common electron acceptors used by them are Nitrate NO3-, Sulphate SO42- or sulphur S,Iron,mercury and manganese.So in this way they undergo respiration and survive without oxygen.
Kinetic Molecular Theory states that gas particles are in constant motion and exhibit perfectly elastic collisions.The average kinetic energy of a collection of gas particles is directly proportional to absolute temperature only.
