1. which organism is able to cause an infection?
a. red blood cell
b. virus
c. bacteria
d. white blood cell

2. how do single-celled decomposers get energy?

a. they use a process called budding.
b. they feed on living organisms
c. they make their own food
d. they break down dead organisms

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