Natality refers to

• Death rate

• Birth Rate

• Number of individuals entering a habitat

• Number of individuals leaving the habitat

Match the items given in Column I with those in Column II and select the correct option given below:

Column I		Column II
a	Herbarium	i	It is a place having a collection of preserved plants and animals
b	Key	ii	A list that enumerates methodically all the species found in an area with brief description aiding identification
c	Museum	iii	Is a place where dried and pressed plant specimens mounted on sheets are kept
d	Catalogue	iv	A booklet containing a list of characters and their alternates which are helpful in identification of various taxa.

• a	b	c	d
  (i)	(iv)	(iii)	(ii)

• a	b	c	d
  (iii)	(ii)	(i)	(iv)

• a	b	c	d
  (iii)	(iv)	(i)	(ii)

• a	b	c	d
  (ii)	(iv)	(iii)	(i)

The direction of energy flow is

•  Producers → Herbivores → Decomposers → Omnivores

• Producers → Carnivore → Herbivores → Decomposes

• Decomposers → Carnivores → Herbivores → Producers

• Producers → Herbivores → Carnivores → Decomposers

If the Bengal tiger become extinct

• Hyenas and wolves will become scarce

• Its gene pool will be lost forever

• The wild areas will be safe for man and domestic

• The population of beautiful animals like deer will get stabilised

55.

Stability of ecosystem depends upon

• Primary productivity

• Interchange between producers and consumers

• Number of producers

• Number of consumers

Overlapping region between two ecosystems is called

• Biome

• Ecotone

• Niche

• Photic zone

Which important green-house gas, other than carbon dioxide, is being produced from the agricultural fields?

• Arsine

• Sulphur dioxide

• Ammonia

• Nitrous oxide

The term 'aquaculture means

• Aspergillosis

• Inland fisheries

• Marine fisheries

• Both (b) and (c)

Ten percent law of energy transfer in a food chain is given by

• Schimper

• Elton

• Haeckel

• Lindemann

Benthic organisms are found in

• surface of marine water

• middle of water in sea

• bottom of sea

• on ground