Chapter 40, Problem 1MC

Summary Introduction

Introduction:

The senses provide information to the brain about the nature and intensity of the environmental stimuli. Nature of the stimulus can be “light and sound” and intensity is defined by the strength of the stimulus, such as “loud or soft sound, dim or bright light”, and so on.

The special senses like taste, vision, hearing, smell, and touch carry stimuli from the sensory receptors and transmit these impulses towards brain for interpretation.

Answer to Problem 1MC

Correct answer:

Sensory receptors that respond to movement, gravity, or sound are mechanoreceptors. Therefore, option (b) is correct.

Option (b) is given as “mechanoreceptor”.

Explanation of Solution

Justify reason for the correct statement:

Mechanoreceptors are a specific sensory receptor. They track the changes in touch/ pressure/ tips (such as finger, hearing, lips, balance and body position). It generates receptor potentials when their membranes are depressed or stretched. Mechanoreceptors are present all over the body parts, skin (that senses to touch, pressure, or vibration), internal organs (such as the stomach, intestine, urinary bladder, and muscles), and inner ear (that senses sound, movement or gravity).

Hence, option (b) is correct.

Justify reasons for the incorrect statements:

Option (a) is given as “Chemoreceptors”.

Chemoreceptors are sense specific receptors present on the taste buds, the lining of the nasal cavity (olfactory receptors), and in internal receptors like blood $\text{pH}$. Hence, it is a wrong answer.

Option (c) is given “photoreceptors”.

Photoreceptors are sense specific receptors that sense visible light such as the eye. Hence, it is a wrong answer.

Option (d) is given as “thermoreceptors”.

Thermoreceptors sense temperature changes that occur in the skin. Hence, it is a wrong answer.

Hence, options (a), (c), and (d), are incorrect.

Conclusion

Mechanoreceptors are located in all over the human body and sense all physical deformation such as bending, dimpling, and stretching that occurs in various parts of the body.