Justify the following statements :
(i) Liver is the "chemical laboratory of the body
(ii) Bile has no enzyme, still it is necessary for digestion
(iii) Swallowing and breathing cannot occur
simultaneously
(iv) Malnutrition is different from undernutrition.
(v) Roughage does not provide any energy or materials
for maintenance of body but still it must be present in
the diet.
Answers
Answer:
(I) liver is the chemical laboratory of the body
Explanation:
1. Liver filters the blood from harmful substances such as drugs and alcohol.
2. Liver produces important chemical substances such as albumin, bile and precursors for clotting factors
3. Liver stores fat soluble vitamins such as vitamin A, D, E, and K.
4. Liver also processes glucose into glycogen and vice versa
(ii) Bile has no enzyme but is necessary for digestion because
- it causes emulsification of fats which helps in making of chylomicrons and eases in their digestion by increasing surface area
- bile is alkaline in nature, so it neutralises the acidic chyme that comes from the stomach, this helps in digestion because most intestinal enzymes do not work in acidic environment
(iii) Swallowing and breathing cannot occur simultaneously because at the time of swallowing the epiglottis is pushed back against the opening of the trachea thus shutting it down.
(iv) malnutrition is different from undernutrition since malnutrition refers to lack of one or more vital nutrients which constitute a balanced diet whereas undernutrition refers to reduced quantity of nutrients but involving a balanced diet
( v) Roughage is necessary for a balanced diet since it absorbs water and helps in bulk movement which is necessary for healthy bowel movement and excretion of feces