yes
Mammals have nervous, digestive, circulatory, skeletal, immune, muscular, integumentary, and excretory systems.
Yes, fleas do have immune systems, though they are simpler than those of mammals. Their immune system primarily consists of innate defenses, such as cellular responses and antimicrobial peptides that help protect them against pathogens. Fleas can respond to infections, but their immune capabilities are not as complex as those found in more advanced organisms.
lymphokines
yes
Your immune system or your live, but you have to have healthy liver to filter out all your diseases.
Depression lowers everyone's immunity. Everything is depressed, not just the mood.
Respiratory and Immune Systems
Respiratory and Immune Systems
Birds and mammals both have internal skeletons, closed circulatory systems, similar digestive systems, and are warm blooded.
The immune system
Yes, most of the time the immune system weeds out cells that are abnormal.
All small dogs have lower immune systems, their sugar levels drop quicker then big dogs.