Molten material is allowed to solidify into the final shape.
Casting defects occur during solidification:
Gas porosity
Shrinkage
Two stages of solidification:
Nucleation
Growth
Evolution occurs when<span>these heritable differences become more common or rare in a population, either non-randomly through natural selection or randomly through genetic drift
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They are involved in a chemical digestion.
Chemical digestion involves breaking down the food into simpler nutrients that can be used by the cells. It begins in the mouth when food mixes with saliva which contains enzyme salivary amylase that breaks down carbohydrates. It also occurs in the stomach where HCl and pepsin forms chyme and small intestine especially in the duodenum.