Question

Assertion – Skin is the sensory organ for touch and is also the largest sense organ.
Reason – Our sense of touch is associated with a general sensation of contact, pressure, heat, cold, and pain.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect

Answer 1

Hint: The sensations of touch, pain, cold, heat, and pressure are different types of stimuli that are picked up by different sensory neurons whose nerve endings are present in the skin.

Complete answer:
With an average total area of about 20 square feet in adults, the skin is considered as the largest sensory organ of the integumentary system in the human body. Our skin is primarily involved in functions like protection from various microbes, regulating the body temperature, permitting the sensations of touch, cold, heat, etc. It also performs the function of thermoregulation with the help of sweat glands, dilated blood vessels, and at the same time, it reduces excess fluid loss from the body by providing a relatively dry and semi-impermeable barrier. It is naturally a water-resistant barrier that prevents essential nutrients from being washed out of the body. The touch sensation in the skin is due to the presence of nerve endings throughout the skin. It contains a variety of nerve endings that are capable of receiving different types of stimuli related to touch i.e. pressure, vibration, heat, cold, etc.

So, the correct answer is “Both Assertion and Reason are correct and Reason is the correct explanation for Assertion”.

Note:
- The neurons present in the skin are generally sensory neurons and they carry signals from the outer parts of our body like the eyes, skin, nose, tongue, etc. to the central nervous system of our body.
- Motor neurons differ from these sensory neurons as the motor neurons are primarily involved in conducting signals from the spinal cord to the muscles. When we receive a sensation on the skin, it is carried to the central nervous system via sensory neurons, the received information is processed there and then an appropriate signal is sent to the related muscle by the central nervous system via motor neurons.