Carbon dioxide, oxygen, water, and acids may all cause chemical weathering. Mechanical weathering is the process of breaking a large rock into smaller pieces without changing the minerals in the rock. Mechanical weathering may be caused by frost, ice, plant roots, running water, or heat from the sun.
Peristalsis<span> is a radically symmetrical </span><span> contraction and relaxation of muscles</span><span> that propagates in a wave</span><span> down a tube, in an anterograde direction.</span>
Animals use the respiratory system to breathe in oxygen and other gases and expel gases like CO2, right? O2 in, CO2 out.
By the amount layers the epithelial tissue has
