ANIMAL PHYSIOLOGY
DIGESTION IN HUMANS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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a chemical reaction takes place
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no new substances are produced
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an enzyme converts one chemical into another
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food is not broken into smaller pieces but just mixed
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Detailed explanation-1: -During the process of digestion, the food is broken down into smaller molecules. The salivary glands present in our mouth help in the breakdown of the food. In this process, there is a formation of a new substance. Therefore, it is considered to be a chemical change.
Detailed explanation-2: -Physical changes are changes in the physical properties of substances. No new substances are formed in these changes. These changes may be reversible.
Detailed explanation-3: -Digestion of food is an example of a physical change.
Detailed explanation-4: -When food is physically changed, mechanical digestion occurs. Food is broken into smaller parts and mixes continually with enzymes and other gastric juices. Mechanical digestion occurs in the mouth, stomach, and small intestine. Food is chemically changed in digestion when new, smaller substances are formed.