41 Which one of the following is important for the normal functioning of plant cell?

Rigidity

42 The purpose of a filament in radio tube is to

Emit electrons

43 The thin epithelium which lines the inside of the eyelids and continues across the front of the eyeball, where it is transparent is called

Conjunctiva

44 The release of energy from food material by a process of chemical reaction which does not require oxygen is called

Anaerobic respiration

45 The release of energy from food material by a process of chemical reaction which requires oxygen is called

Aerobic respiration

46 The rate of change of distance moved with time is called

Speed

47 The canal rays are

A stream of positively charged particles

48 As the number of micro-organisms in a soil increases, the amount of humus in the soil

Increases

49 The two testes, which are the male reproduction organs, lie outside the abdominal cavity, in a special sac called

Scrotum

50 A membrane of skin and fine fibres is stretched across the innermost end of the outer ear, closing it off completely. This membrane is called

Oval window