51.
The development of a bare area without any life form is called

52.
_________ is a long term pattern of weather at a particular area.

53.
The lowest temperature is usually observed:

54.
Species that occur in different geographical regions separated by special barrier are:

55.
The crucial species that determine the ability of large number of other species is termed as _________ species.

56.
World's first Teak Forest was planted in 1842 in Kerala. Identify the place.

57.
Pottery workers are at high risk of __________ lung disease.

58.
The strongest radiation inversions occur when

59.
The darkening of the skin due to arsenic poisoning is called

60.
A change of one degree on the Celsius scale is ____ a change of one degree on the Fahrenheit scale.