Do all living things (man, animals, mammals) have blood?

No, not all living things have blood. For example, Protista and bacteria don't have blood because they are unicellular. One definition of blood states “Blood is a body fluid in humans and other animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells.” . read more

Best Answer: Not every living creature, most members of the kingdom Animalia however do. This includes all insects, mammals, spider, crabs, fish etc. Not all blood is red though. The colour of blood is dependent on the molecule used to transport oxygen around the body. read more

No. Many animals have no heart or even a separate circulatory system. In very small animals there's no need for an organ to transport nutrients through the body; diffusion is sufficient. Most of the major groups of animals (phyla) do not have hearts. Sponges have no hearts. They have no organs at all. read more