Organisms and Populations

Consider the following four statements (i)–(iv) about certain desert animals such as kangaroo-rat. (i) They have dark colour and high rate of reproduction and excrete solid urine (ii) They do not drink water, breathe at a slow rate to conserve water and have their body covered with thick hairs (iii) They feed on dry seeds and do not require drinking water (iv) They excrete very concentrated urine and do not use water to regulate body temperature Out of these four, which two are correct?

1. (i) and (ii)
2. (ii) and (iii)
3. (iii) and (i)
4. (iii) and (iv)

Quercus species are the dominant component in:

1. Temperate deciduous forests
2. Alpine forests
3. Scrub forests
4. Tropical rain forests

Geometric representation of age structure is a characteristic of :-

1. Biotic community
2. Landscape
3. Ecosystem
4. Population

The population of an insect species shows an explosive increase in numbers during rainy season followed by its disappearance at the end of the season. What does this show ?

1. The food plants mature and die at the end of the rainy season
2. The population of its predators increases enormously
3. Its population growth curve is of J-type
4. S-shaped or sigmoid growth of this insect

A high density of elephant population in an area can result in :-

1. Mutualism
2. Interspecific competition
3. Predation on one another
4. Intraspecific competition

Annual migration does not occur in the case of

1. Arctic tern
2. salmon
3. Siberian crane
4. salamander

The formula for exponential population growth is-

1. dN/dt = rN
2. dt/dN = rN
3. rN/dN = dt
4. dN/rN = dt

Praying mantis is a good example of-

1. Warning colouration
2. Camouflage
3. Mullerian mimicry
4. Social insects

Niche overlap indicates-

1. Sharing of one or more resources between the two species
2. Mutualism between two species
3. Active cooperation between two species
4. Two different parasites on the same host

More than 70% of world's fresh water is contained in –

1. Polar ice
2. Greenland
3. Antarctica
4. Glaciers and Mountains