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Punctuated equilibrium is a series of small, gradual changes over long periods of time.
the tiny blood vessels surrounding the alveoli are called capillaries.
the capillaries have thin walls and are connected to the larger blood vessels ( veins) and they bring oxygen to the heart threw oxygenated blood.
Cell differentiation is the process by which cells specialize to achieve their required functions. In order for a cell to differentiate, it will express specific genes. ... Importantly, mitosis produces cells that are identical to each other (clones).
