Tcells often function to decrease the immune response release b7 proteins function in the adaptive immune system activation bind tightly to target cells and release a lymphotoxin called perforin

"do a testcross with a homozygous recessive plant."

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands