Which statement accurately describes the chemical and biological properties of saliva in a healthy human?
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Answer: C. It is slightly alkaline
Explanation
Normal resting human saliva is slightly alkaline, generally maintaining a pH range between 6.2 and 7.6. The chemical composition of healthy saliva ensures optimal oral health and helps in initial starch digestion. Maintaining an alkaline pH prevents enamel demineralization and supports healthy microbial balance in the human mouth. Saliva is an exocrine secretion produced by the major and minor salivary glands located in the oral cavity. Water constitutes over ninety-nine percent of human saliva, while the remaining portion contains electrolytes and proteins. Salivary amylase is a major digestive enzyme present in saliva that initiates carbohydrate breakdown during mastication.
Option A is incorrect because healthy human resting saliva is not acidic, which would promote dental enamel erosion. Option B is incorrect because saliva is not significantly saline or salty in its normal physiological condition. Option D is incorrect because the typical pH range leans slightly above neutral rather than resting at exactly seven.
- Subject
- Everyday Science
- Category
- Everyday Science
- Topic
- —
- Difficulty
- medium
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