<span>Mammals are advanced synapsids, animals distinguished by having extra openings in the skull behind the eyes; this opening gave the synapsids stronger jaw muscles and jaws (the jaw muscles were anchored to the skull opening) than previous animals.
Synapsids include the mammals, and their ancestors, the pelycosaurs, therapsids, and cynodonts. Pelycosaurs (like Dimetrodon and Edaphosaurus) were early synapsids, they were mammal-like reptiles. Later synapsids include the therapsids and the cynodonts (with multicusped post-canine teeth; they lived from the late Permian through the Triassic period).
The cynodonts led to the true mammals. Over time, the synapsid gait became more upright and tail length decreased</span>
I think it’s b but idk i’m learning that in science as well
C) a system is a set of parts that function together as a whole
After the macrophage fails the Helper T Cell stimulates the B cells if pathogen is extracellular and Cytotoxic T Cells if the pathogen is intracellular. Once the pathogen is killed the B Cells create Memory B Cells and the Killer T Cells create memory T Cells.
