Shivansh Shukla

LIFE PROCESSES

Q1: What is the difference between starch and sugar?

A1: Starch and sugar are both a part of a large group known as carbohydrates, the difference between both of them is that sugars are simple units of specific molecules such as glucose, fructose etc. While, starches are complex chains of sugar molecules linked together.

Q2: What is the function of salivary amylase?

A2: Salivary amylase breaks down starch into simpler carbohydrates. This amylase is a bio-catalyst and is present in the saliva that is secreted by certain glands in our buccal cavity.

Q3: What is the pH level of our mouth?

A3: Our mouth's pH has a range of around 6.2 to 7.6 with 6.7 being the average pH.

Q4: What is the function of these substances secreted in our stomach:

1) HCl: The hydrochloric acid present in our stomach helps in the breakdown of protein, also, it helps in activating pepsinogen into the enzyme pepsin.

2) Mucus: As the walls of our stomach are tender and can be damaged by the gastric juices, mucus helps in protecting the lining of the stomach against any possible damage.

3) Gastric juice: The gastric juice plays a crucial role in digestion as it secretes pepsinogen, which later on, as pepsin, helps in further digestion of food. Apart from this, it helps in killing some unwanted, harmful microbes.