Practice Questions

Correct answer is അൾട്രാവയലറ്റ്

ജലത്തിലുള്ള സൂക്ഷ്മ ജീവികളെ നശിപ്പിക്കുന്നതിന് ഉപയോഗിക്കുന്നത് :






Vitamin D2 (ergocalciferol) is largely human-made and added to foods
Vitamin D3 (cholecalciferol) is synthesized in the skin of humans from 7-dehydrocholesterol and is also consumed in the diet via the intake of animal-based foods.
Vitamin D is a closely related compound. The synthesis of this vitamin starts when the precursor molecules are activated in the skin by the UV (ultraviolet) rays in the sunlight.
In the kidneys and the liver, the enzymes then modify the molecule ultimately yielding calcitriol, which is the most active form of vitamin D.
This calcitriol supplies the homeostasis of body fluids by assisting the process of absorption of calcium in the food.
As per the synthesis sequence explained, vitamin D is deemed to be a hormone as it is yielded in the body in one location and transported by the blood, and shows effect in the other location.
Hence, skin is deemed to be an endocrine organ.


Which of the following is necessary for the dermal synthesis of Vitamin D ?

Which of the following has the highest wavelength?

The frequency of ultrasound wave is typically ---?

Which type of light waves/rays used in remote control and night vision camera ?

Electromagnetic waves with the shorter wavelength is

The angle of refraction is 90°, meaning the light will travel along the interface between the optical fiber and air.
This particular angle of incidence is called the critical angle. Here the angle of refraction is 90 degrees. When the angle of incidence is greater than the critical angle, the incident ray is reflected back to the medium

Challenger App

No.1 PSC Learning App