Permafrost condition is a characteristic feature of:

Which of the following is the most ecologically relevant environmental factor?

Match the following columns:

Column-$I$ (Temperature)	Column-$II$ (Habitat)
$P$. Sub-zero levels	$I$. Thermal springs
$Q$. Can exceed $50^{\circ}C$	$II$. Polar regions
$R$. Can even exceed $100^{\circ}C$	$III$. High altitude areas
	$IV$. Deep-sea hydrothermal vents
	$V$. Tropical deserts

Which one of the following factors is biotic?

At which latitude,heat gain through insolation approximately equals heat loss through terrestrial radiation?

Write a short note on:
$(a)$ Adaptations of desert plants and animals
$(b)$ Adaptations of plants to water scarcity
$(c)$ Behavioural adaptations in animals
$(d)$ Importance of light to plants
$(e)$ Effect of temperature or water scarcity and the adaptations of animals.