During total internal reflection when the ray in the denser medium reaches to the critical angle, the angle in the rare medium will be:
a) 600
b) 900
c) 1200
d) 1800
Most of the refraction is done at the front surface of the ___ at its interface with air:
a) Iris
b) cornea
c) Lens
d) All of them
Explanation: Most refraction in the eye occurs when light rays travel through the curved, clear front surface of the eye (cornea). The eye's natural (crystalline) lens also bends light rays.
An example of flowers pollination by water is:
a) Grass species
b) Conifers
c) Hydrilla plant
d) Chestnuts
Explanation: Hydrilla and Vallisneria- These are the plants that grow in freshwater. The male flower or pollen grains are released on the surface of the water. These pollen grains are carried slowly by water currents and reach the stigma of the female flower.
The type of linkage present between nucleotides is:
a) Glycosidic
b) Puriness
c) Peptide
d) Phosphodiester
Explanation: Phosphodiester bond: It acts as the connection between two nucleotides or adjacent nucleotides in the DNA strand.
The locus of all the points having same phase in a medium is known as:
a) Coherent phase
b) Interference
c) Wave
d) Wave front
Explanation: Wavefront is the locus of all points, where the particles of the medium vibrate with the same phase
Each surface of a lens is a part of a sphere, the center of which is called as:
a) Optical Center
b) Center of Curvature
c) Focal point
d) Principal focus
Explanation: The center of the imaginary glass sphere of which the lens is a part is known as the center of curvature (C). It is found at a point that is at a distance from the curve equal to the radius of curvature lying on the normal vector. It is the point at infinity when the curvature is zero. 
