A donor offspring is the donation of sperm
The immune system works with the digestive tract to help protect you from infection by these potential invaders. Your immune system also depends upon cells to kill invading organisms, and chemicals that don't require the involvement of cells at all, but which are simply toxic to bacteria and viruses. Acid in the stomach does the same thing.
B. The organisms physical traits.
A phenotype refers to all observable traits of an organisms as a result of its genotype.
It’s white blood cells they help fight off any virus or disease
