Poliomyelitis (polio) is a highly infectious and debilitating disease caused by the poliovirus, which can invade the nervous system and cause paralysis.
47. Rickets caused by the deficiency of
(A) vitamin A
(B) vitamin C
(C) vitamin B1
(D) vitamin D
Answer:
(D) vitamin D
Explanation:
Rickets is a skeletal condition in children characterized by weak, soft bones, directly caused by a prolonged deficiency of Vitamin D, which is essential for calcium absorption.
48. Ants move in a line because of their sense of
(A) sight
(B) smell
(C) blood
(D) sound
Answer:
(B) smell
Explanation:
Ants have an extremely advanced sense of smell and navigate by following invisible chemical trails (pheromones) left on the ground by other ants in their colony.
49. Which is the longest organ of the digestive system in human body?
(A) stomach
(B) large intestine
(C) small intestine
(D) rectum
Answer:
(C) small intestine
Explanation:
Despite its name (which refers to its narrow diameter), the small intestine is the longest section of the digestive tract, measuring about 20 to 23 feet long in a human adult to maximize nutrient absorption.
50. Mangoes can be preserved by
(A) Boiling
(B) pasteurisation
(C) pickling
(D) cooling
Answer:
(C) pickling
Explanation:
Pickling raw mangoes in salt, spices, and oil (making traditional Indian Achaar) prevents bacterial growth and preserves the fruit, allowing it to be consumed long past its harvest season.
