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.
It is the circulatory system and respiratory system.
The air that we breathe in is an example of solid solution
<em>A.) Traits Skipping One Or More Generations</em>
The difference in water concentration across a selectively permeable membrane.