Commercially important cotton fibers are

• epidermal hairs of seeds

• woody fibers of roots

• phloem fibres of roots

• phloem fibres of roots

A member of Liliaceae that shows reticulate venation is

• Scilla

• Smilax

• Aloe

• Aloe

Euphenics is

• manipulation of genes

• improvement of race

• study of conditions affecting organisms

• study of conditions affecting organisms

Araneology is

• rearing of bees

• study of aphids

• study of spiders

• study of spiders

What does 'Corpus luteum' secrete?

• Testosterone

• Estrogen

• Haemoglobin

• Haemoglobin

The male sex hormone is

• estrogen

• testosterone

• insulin

• insulin

The total energy of an electron inside an atom is

• zero

• more than zero

• less than zero

• less than zero

The velocity of light is

79.

A seconds pendulum is a pendulum whose time period is

• 4 s

• 3 s

• 2 s

• 2 s

A jug is filled to the brim with water at 0°. A piece of ice floats in it. The moment the ice melts,

• water level increases

• water level decreases

• water level is unchanged

• water spills out of the jug