Biology
Thomas was travelling in the train from Ranchi to Kanyakumari. It was a long journey. On getting down from the train, he felt that he is still moving. What could be the possible reasons for this experience ?
P: The semicircular canals, which maintain dynamic balance, take some time to return to normal after continuous motion.
Q: The parts of membranous labyrinth (utriculus and succulus) responsible for static balance take time to become active.
R: He was tired, so he felt dizzy.
S: The fluid in the semi-circular canals was still shaky.
- P and Q
- Q and R
- P and S
- P and R
Answer
P and S
Reason — The semicircular canals contain a fluid called endolymph. During the long train journey, these canals continuously sensed motion. When Thomas got down from the train, the endolymph did not stop moving immediately. This created a false sensation of movement, making him feel that he was still moving.
Related Questions
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Reason (R): Lacrimal gland is located in the upper outer portion of the orbit of the eye. Tears act as a lubricant and also have antiseptic property.
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