What is upwelling? the productivity of an ecosystem
water moving up from the benthic zone
when infertile species reproduce
the mixing of two biomes

i think the answer is b.

hope it

hormones in blood stream

image: dtc.ucsf.edu

endocrine glands secrete hormones into the blood stream near them; the hormones then travel in our bloodstream until it reaches its destination, called a target cell, in distance parts of the body. in the target tissue, hormones lock onto the target’s plasma membrane, called the receptor site.