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The Water Cycle01:00

The Water Cycle

The Earth’s hydrosphere includes all of the areas where the storage and movement of water occurs. Since water is the basis of all living processes, the cycling of water is extremely important to ecosystem dynamics.
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Role of Water in Human Biology01:27

Role of Water in Human Biology

Water is the one of the most significant components of the human body; it plays a crucial role in several physiological activities because of its unique physicochemical properties. Importantly, it helps to regulate body temperature and is the chief component of several body fluids.
Water's Solvent Properties
Since water is a polar molecule with slightly positive and slightly negative charges, ions and polar molecules can readily dissolve in it. Therefore, it is referred to as a solvent, a...
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Fluid Movement Between Compartments01:18

Fluid Movement Between Compartments

The force applied by fluids against a surface, known as hydrostatic pressure, initiates the transfer of fluid among different compartments. Within our blood vessels, the blood's hydrostatic pressure is a result of the heart's pumping action. At the arteriolar end of capillaries, hydrostatic pressure (capillary blood pressure) exceeds the opposing colloid osmotic pressure created primarily by plasma proteins like albumin. This discrepancy in pressure propels plasma and nutrients from the...
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Xylem and Transpiration-driven Transport of Resources02:03

Xylem and Transpiration-driven Transport of Resources

The xylem of vascular plants distributes water and dissolved minerals that are taken up by the roots to the rest of the plant. The cells that transport xylem sap are dead upon maturity, and the movement of xylem sap is a passive process.
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Body Water Content and Fluid Compartments01:19

Body Water Content and Fluid Compartments

Life's biochemical processes occur within aqueous solutions. Solutes are substances that are dissolved within these solutions. The human body contains a variety of solutes, which can differ across various body parts. These can encompass proteins—such as those responsible for clotting and carbohydrate transport—as well as electrolytes. In medicine, an electrolyte is often described as a mineral ion derived from a salt possessing an electric charge. Examples include sodium ions...
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States of Water01:23

States of Water

Water exists in any one of the three classical states: solid (ice), liquid (water), and gas (steam or water vapor). The state of water depends on i) the intermolecular forces that draw molecules together and ii) the kinetic energy that leads to movements that pull them apart.
Water freezes when the intermolecular forces are greater than the kinetic energy. Unlike most other substances, water is less dense in its solid state than in its liquid state. This is because each water molecule can form...
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