Read the passage carefully and give the answers to the next five questions :
Does the number of species in a community really matter to the functioning of the ecosystem? This is a question for which ecologists have not been able to give a definitive answer. For many decades, ecologists believed that communities with more species. generally. tend to be more stable than those with less species. According to the International Union for Conservation of Nature and Natural Resources (IUCN) (2004), the total number of plant and animal species described so far is more than 1.5 million
Which of the following is not a characterstic of a stable biological community ?
A stable community should not show too much variation in productivity from year to year; it must be either resistant or resilient to occasional disturbances (natural or man-made), and it must also be resistant to invasions by alien species.
The 'rivet popper hypothesis' of Paul Ehrlich is an analogy where the ecosystem is compared to an airplane and species are compared with the rivets. In an aeroplane (ecosystem) various parts (components of an ecosystem) are joined together by thousands of rivets (species).
It was David Tilman proposed that " stability of a community depends on its species richness".
Among vertebrates, fishes form the most species rich group.
Tropics have greater biological diversity. Ecologists and evolutionary biologists have proposed various hypotheses; some important ones are:
(a) Speciation is generally a function of time, unlike temperate regions subjected to frequent glaciations in the past, tropical latitudes have remained relatively undisturbed for millions of years and thus, had a long evolutionary time for species diversification.
(b) Tropical environments, unlike temperate ones, are less seasonal, relatively more constant and predictable. Such constant environments promote niche specialisation and lead to a greater species diversity and
(c) There is more solar energy available in the tropics, which contributes to higher productivity; this in turn might contribute indirectly to greater diversity.
English
50 Questions
200 Marks
45 Mins EnglishMatch Column ‘A’ with Column ‘B’ and select the suitable answer from the codes given below:
Column I | Column II |
|---|---|
A. Leishmania donovani | {i}Malaria |
B. Wuchereria bancrofti | {ii}Amoebiasis |
C. Trypanosoma gambiense | {iii}Kala azar |
D. Entamoeba histolytica | {iv}Sleeping sickness |
(v) Filariasis |
Which of the following statement(s) is/are correct?
{i}Collagen is the most abundant protein in animals.
{ii}RuBisCO is the most abundant protein in plants.
{iii}Z-DNA is the most common double helical structure found in nature.
Match Column I (taxonomic rank) with Column II (example/term) and choose the correct code.
Column I | Column II |
|---|---|
A. Family | {i}Solanum |
B. Kingdom | {ii}Solanaceae |
C. Order | {iii}lycopersicum |
D. Species | {iv}Plantae |
E. Genus | (v) Solanales |
Given below are two columns:
Column I lists the names of scientists and Column II lists the discoveries made by them towards understanding photosynthesis in plants.
Match the scientists with the corresponding discoveries and choose the correct code.
Column I | Column II |
|---|---|
A. J.B. Van Helmont | {i}Starch is the first visible product of photosynthesis |
B. Stephen Hales | {ii}Water of soil contributes to the growth of plants |
C. Engelmann | {iii}Green plants get nourishment through their leaves from air and sunlight |
D. Sachs | {iv}Action spectrum of photosynthesis |
Match the components of the Electron Transport System (ETS) of aerobic respiration with their respective electron carriers.
Column I | Column II |
|---|---|
A. Complex I | {i}Cyt c → O₂ |
B. Complex II | {ii}NADH → CoQ |
C. Complex III | {iii}Succinate → CoQ |
D. Complex IV | {iv}CoQH₂ → Cyt c |
Observe the columns and match the plants/types in Column I to the morphological forms in Column II.
Column -I | Column- II |
|---|---|
A. Scape | i. Tinospora |
B. Culm | ii. Grasses |
C. Liana | iii. Onion |
D. Creeper | iv. Bamboo |
Choose the correct answer from the codes given below:
Consider the statements — identify the incorrect ones:
A. Inulin is a polymer of fructose.
B. Starch is present as storehouse of energy in plants.
C. Cellulose is a polymer of sucrose.
D. Chitin is a heteropolymer.
Choose the correct answer:
Human placenta is derived from:
Hormones secreted by the placenta to maintain pregnancy are:
Match Column ‘A’ with Column ‘B’ and select the suitable answer from the codes given below:
Column I | Column II |
|---|---|
A. Leishmania donovani | {i}Malaria |
B. Wuchereria bancrofti | {ii}Amoebiasis |
C. Trypanosoma gambiense | {iii}Kala azar |
D. Entamoeba histolytica | {iv}Sleeping sickness |
(v) Filariasis |
