What do you see as restrictions to the models when comparing them to actual human body?

they absorb it i think

not sure

you

the second type of galaxy is called a barred spiral, which has a thing called a bar straddling the nucleus

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