We should save the document regularly when working on the document. If the app breaks down, you'll still have the file with your progress. To be extra safe, save the document in multiple places including the computer itself, also your USB drive. just so in case if the computer breaks down, you still have your USB drive.
This question is not clear, but I think I understand what you are asking. The difference between alleles of a gene is that some alleles may be dominant or recessive. If one gene has more dominant alleles than another, than it will be more visible.
Antigens are proteins that are found on the surface of the pathogen and are viruses, fungi, or bacteria. Nonliving substances such as toxins, chemicals, drugs, and foreign particles. Antigens are usually carried by proteins and polysaccharides, and less frequently, lipids but it also needs to be attached to a large carrier molecule which is usually a protein. When an antigen enters the body, the immune system produces antibodies against it. The Antigen stimulates the immune system to produce antibodies. YOUR WELCOME ;)
