Which organ is essential in circulating oxygen throughout the body?
a. liver
b. heart
c. lung
d. kidney

The asian shore crab (hemigrapsus sanguineus) is an invasive species that has impacted the atlantic coast. predict what characteristic of this invader would most likely disrupt the biodiversity of this area.

15 ! come and answer! a(n) is the general term for an infectious disease that has spread across a city, region, or country.

What organelle other than the nucleus houses dna in a eukaryotic cell?