Final answer:
Metabolism can both positively and negatively affect the immune system depending on various factors such as stress. Innate immunity is suggested to have evolved first in the common ancestors of invertebrates and vertebrates, with vertebrates later developing an adaptive immune system.
Step-by-step explanation:
Impact of Metabolism on the Immune System in Vertebrates
The relationship between metabolism and the immune system in vertebrates is not as straightforward as the options presented A) through D) seems to imply. In general, a healthy and well-functioning metabolism supports the immune system, but the impacts of increased or decreased metabolism on the immune system can vary depending on numerous factors such as stress, infection, and overall health. Option C) is partially correct as chronic stress or other factors leading to consistently increased metabolism may impair the immune system over time.
Regarding the evolution of immune systems, it is suggested that innate immunity evolved first. It is present in both invertebrates and vertebrates, indicating that their common ancestor had an innate immune system. Vertebrates later developed an adaptive immune system, which allows for more specific responses to pathogens and the ability to remember previous infections, thereby providing enhanced protection upon re-exposure to the same pathogens.
Vertebrate Immune System Evolution
Research into the immune system of vertebrates shows that it is complex, with multiple layers and unique defenses, including specific pathogen recognition and memory mechanisms. These defenses are part of the adaptive immune system, which combined with the innate immune system, provide vertebrates with a multi-faceted approach to fighting infections and diseases.