Active muscles demand huge amounts of oxygen, and the circulatory system works hard to provide it. Blood carries oxygen to the muscles. When the body is at rest, blood carries nutrients to the muscles so that they can repair and rebuild themselves. Blood also carries away the waste products that hard-working muscles produce, back out through the lungs to be filtered.
so they Circulatory system xx muscular system :)
Answer:
B..........................
Explanation:
I think it’s Rhizobium I’m not sure though
Cell definition: the basic membrane-bound unit that contains the fundamental molecules of life and of which all living things are composed.
Cytology definition: the study of cells as fundamental units of living things.
I think is c i hope i am right if not that k k
Just let me know k