Organisms and population practice · Hard

Obligate parasites live on:

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 concenntated urine and do not use water to regulate body temperature.
Which two of the above statements for such animals are true?

Which of the following factors (given below) determines the vegetation of any area?

(i) $\mathrm{pH}$ of soil.

(ii) Mineral compositon of the soil.

(iii) Water holding capacity of soil.

(iv) Precipitation.

Assertion (A) :Smaller the organism, higher is the rate of metabolism per gram weight

Reason (R) : The heart rate of six months old baby is much higher than that of an old person

Assertion: The community of an ecotone
commonly contains the organisms of each of
the overlapping communities and in addition the
organisms which are restricted to the ecotone.

Reason: The tendency for increased variety and
density at community junctions is known as the
edge effect.

Pseudo copulation occurs in

Assertion: Plants need the help of insects and
animals for pollinating their flowers and
dispersing their seeds.

Reason: Plants offer rewards in the form of pollen
and nectar for pollinators and juicy and nutritious
fruits for seed dispersers.

Which of the following is not a defence evolved by a prey to avoid predators?

Choose the correctly matched option:-

A population of 500 experiences 55 births and 5 deaths during a one-year period. What is the reproductive rate for the population during the one-year period?

The mimicing of monarch butterfly by the viceroy butterfly is an example of

(A): An orchid growing as an epiphyte on a mango branch is an example of commensalism.

(R): In this interaction, the mango tree is benefited while the orchid derives no apparent benefit.

Assertion: Predators not only take the old, sick
and young individuals but also the healthy
individuals.

Reason: If predators kille only the old, sick and
young prey individuals, then there would be no
evolution of antipredatory traits in the prey
population.

Mycorrhizae help in absorption of:

I. The human liverfluke, a nematode parasite, depends on two intermediate hosts (snail and pig) to complete its life cycle
II. The malaria parasite needs a vector (mosquito) to spread to other hosts
III. The female mosquito is not considered parasite, however it needs our blood for reproduction
IV. In case of brood parasitism, the eggs of parasitic birds (e.g.,cuckoo) are not detected and ejected from the nest because of parasite’s eggs resemble the hosts eggs in morphology and colour
V. A population of frogs protected from all predators would increase indefinitely.
Which statements are correct?

Under a particular set of selection pressure, organisms evolve towards the most …A… reproductive strategy. Some organisms breed only …B… in lifetime while others breed …C… in life time
Choose the correct option for A, B and C

Character displacement take place when there is

In which one of the following the birth rate is high & death rate is normal

Assertion: The rate at which a population can
be expected to grow in the future can be
assessed graphically by means of a population
pyramid.

Reason: A triangular population pyramid is
characteristic of a country whose population is
stable, neither growing nor shrinking.

I. Species level II. Population level
III. Individual level IV. Community level
Out of the levels given at a which level selection operates

Mechanical tissue is best developed in:

If ${b}=65$ and ${d}=45, {N}=100$ then find out $\frac{{dN}}{{dt}}.$

Plats which behave as mesophytes in rainy season and as xerophytes in summers are called

In growth pattern, (1 – N/K) is

In aquatic system, actively moving animal organisms are:

Identify the incorrect statement.

(i) Thermoregulation energetically least expensive process for many organisms like shrews and humming birds.

(ii) $99 \%$ animals and nearly all plants cannot maintain their constant internal environment.

(iii) During the course of evolution, the costs and heights of maintaining a constant internal environment are discarded.

(iv) In aquatic animals, the osmotic concentration of the body fluids change with that of the ambient water osmotic concentration.

Photosynthesis in Opuntia is done by

During encystations, Amoeba withdraws its pseudopodia and secretes a ……… layered hard covering or cyst around itself.

Ecotone is

Which one of the following plants is an invasive
species that has spread to many parts of the
Indian subcontinent?