81 Monocotyledons are the flowering plants which have

Narrowed leaves

82 Convection can only take place in

Fluids

83 The blood vessels with the smallest diameters are called

Capillaries

84 The production of excess pigment in the skin is stimulated by mainly by

Ultraviolet rays

85 Hertz is a unit of

Frequency

86 The pH of gastric juice is about

4

87 An organism having the characteristics of both plants and animals is the

Euglena

88 As a ship takes on cargo, the buoyant force of water upon it

Increases

89 When a disease occurs as a regular feature among certain populations of a particular area as under certain conditions, it is called

Endemic

90 Which Vitamin is naturally formed in the skin by the action of sunlight?

Vitamin D