The cells of the innate system recognize and respond to pathogens in a generic way, but, unlike the adaptive immune system (which is found only in vertebrates), it does not confer long-lasting or protective immunity to the host.ll white blood cells (WBC) are known as leukocytes. Leukocytes are different from other cells of the body in that they are not tightly associated with a particular organ or tissue; thus, they function similar to independent, single-cell organisms.
Ideally, the age to bring home a puppy is when heâs between seven and twelve weeks old. This is considered the critical socialization period in a puppyâs life, the time when he learns the most about his environment and begins to adjust to his surroundings.
Legal limits on the age of puppies when sold. In some 25 states in the USA there are legal requirements governing the sale of puppies. In most cases these laws stipulate that puppies should be over 8 weeks old when they go to their permanent homes. So what is the purpose of this legislation and why is 8 weeks so important.