Answer:
The answer is A
By the late 1830s, botanist Matthias Schleiden and zoologist Theodor Schwann were studying tissues and proposed the unified cell theory. The unified cell theory states that: all living things are composed of one or more cells; the cell is the basic unit of life; and new cells arise from existing cells.
Scientific discovery allows us to develop new technologies, solve practical problems, and make informed decisions — both individually and collectively.
Absorbing CO2 into the blood is a part of the respiratory system!
Answer:
adaptation-the inherited characteristic that increases an organism's chance of survival and to reproduce.
fitness -the ability of an organism to survive and reproduce in its environment
