Adaptive immunity can be acquired during either 'naturally' (by infection) or 'artificially' (through deliberate actions such as vaccination). Adaptive immunity can also be classified as 'active' or 'passive'
It is true that unlike erythrocytes, leukocytes have a nucleus and do not contain hemoglobin.
if you had to choose between your family and 50% of the rest of the world most people would not make a logical decision
Stomach, liver, gall bladder, and pancreas
Through mutations in the DNA of bacteria, they can adapt. Only the mutated bacteria would live and keep producing bacteria with the same mutation. Eventually, they would be immune to antibiotics.
