Question

Give reasons.
(1) Food becomes acidic in the stomach.
(2) Cardiac muscles are said to be involuntary muscles.
(3) Intoxicating substances should not be consumed.
(4) Your muscles should be strong and efficient.

Answer 1

a. Food becomes acidic in stomach because of the presence of hydrochloric acid in the stomach. As the food reaches the stomach, it gets mixed with the hydrochloric acid present there. The hydrochloric acid plays the following roles in digestion:

1. It initiates protein digestion by activating the conversion of pepsinogen to pepsin.

2. It provides acidic medium for the activity of pepsin and other enzymes present in gastric juice.

b. Cardiac muscles are said to be involuntary because they are not controlled by our will. These muscles are found in heart and are the only muscles which work throughout the life without getting tired or fatigue.

c. Intoxicating substances should not be consumed because they harm the body directly or indirectly. Substances such as alcohol cause damage to the nervous system and the digestive system as well. Liver is the main organ which is affected by alcohol. Tobacco is one of the leading causes of oral cancer. Smoking has a direct effect on the respiratory system of an individual and can lead to lung cancer as well.

d. Our muscles should be strong and efficient because they carry out various vital functions in our body. From helping us to breath, digest food to helping us in walking and lifting weights, muscles play an important role. If our muscles are not strong enough we would get tired easily and feel fatigue. It is required to keep them in a healthy state by regular exercising and taking proper diet.