Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Chewing is the first step of digestion where teeth break food into smaller pieces. This increases the surface area for enzymes to act upon, expressed as .
Saliva, secreted by salivary glands, contains the enzyme amylase which begins the chemical breakdown of carbohydrates: .
The Tongue helps in mixing food with saliva and contains taste buds to identify Sweet, Sour, Salty, and Bitter flavors.
The Oesophagus (Food Pipe) carries food from the mouth to the stomach through a wave-like muscle movement called peristalsis.
The Stomach is a muscular bag where food is churned and mixed with digestive juices and Hydrochloric Acid () to break down proteins.
The Small Intestine is the longest part of the digestive system where most of the digestion and absorption of nutrients into the blood occurs.
The Large Intestine absorbs water and minerals from the undigested food, leaving behind solid waste.
Proper digestion requires drinking adequate water and eating fiber-rich food (roughage) to prevent constipation.
📐Formulae
💡Examples
Problem 1:
If a piece of bread is chewed for a long time without swallowing, it starts tasting sweet. Why?
Solution:
Bread contains starch. When chewed for a long time, the salivary amylase breaks down the complex starch into simple sugars like maltose.
Explanation:
The chemical reaction involved is:
Problem 2:
Calculate the total number of teeth in an adult human mouth if they have quadrants, each containing incisors, canine, premolars, and molars.
Solution:
Total teeth =
Explanation:
Using basic arithmetic: Total teeth =
Problem 3:
What is the primary function of Hydrochloric Acid () in the stomach?
Solution:
It kills bacteria that enter with food and provides an acidic medium for enzymes to digest proteins.
Explanation:
The stomach maintains a low () to ensure that protein-digesting enzymes like pepsin can function effectively.