White blood cells
white blood cell defends the body against disease.
The immune system is the body system that defends against infection and disease by identifying and fighting off harmful pathogens such as bacteria, viruses, and other pathogens. It consists of a network of cells, tissues, and organs that work together to protect the body.
From your wording, it is impossible to tell which of the following protein-based compounds defends the body against infection and disease. The answer cannot be determined without having options from which to choose.
Nothing
Your immune system.
The type of green vegetable that protects against dementia and Alzheimer's disease I believe is asparagus.
lymphatic
Its presence protects the horse in the stall against any disease.
insect disease
It doesn't cause any disease. It protects against the chicken pox (varicella-zoster) virus.
People build up resistance against some diseases and their immune system protects them against the disease in future infections.
White blood cells are the body's primary defense against infections. They detect and eliminate pathogens like bacteria, viruses, and other harmful substances. White blood cells also help in the body's immune response by producing antibodies and activating other immune cells.