Biology Test 363

Single-step that causes large mutation is called saltation.

It is called as such because the mutation occurs suddenly and abruptly that leads to evolution in large scale.

Hugo de Vries used this term against Darwin’s theory of evolution.

Series of biotic communities that develop in a newly formed pond or lake is called hydrosere. Various seral stages of hydrosere are:

Planktons (Phytoplanktons and zooplanktons) → rooted submerged hydrophytes → floating hydrophytes → reed swamps → sedges or marsh-meadow stage → woodland stage → climax forest.

The extinction of marine species like Steller's Sea Cow was primarily caused by over-exploitation by humans, including hunting and overharvesting.

The largely tropical Amazonian rain forest in South America has the greatest biodiversity on earth- it is home to more than 40,000 species of plants, 3,000 of fishes, 1,300 of birds, 427 of mammals, 427 of amphibians, 378 of reptiles and of more than 1,25,000 invertebrates.

In the given figure, A represents submerged stage (e.g., Hydrilla, Potamogeton, Vallisneria, etc.), B represents floating leaved anchored plant stage (e.g., Nymphaea, Nelumbo, Pistia, etc.), C represents reed-swamp stage (e.g., Phragmites, Typha, Scirpus, Sagittaria, etc.), D represents marsh-meadow stage (e.g., Carex, Cyperus, Juncus, etc.), E represents woodland stage (e.g., Salix, Populus, Alnus, etc.) and F represents the climax community of forest (e.g., Acer, Quercus, Ulmus, etc.).

The list of endangered species is officially released by the International Union for Conservation of Nature (IUCN), which is specified as Option D.

The IUCN is an international organization dedicated to natural resource conservation. They are renowned for their comprehensive "Red List of Threatened Species," which assesses the conservation status of plant and animal species worldwide. This Red List is a critical indicator of the health of the world's biodiversity and provides information on the range, population size, habitat and ecology, use and/or trade, threats, and conservation actions that can help inform necessary conservation decisions.

Other options listed such as GEAC (Genetic Engineering Approval Committee), WWF (World Wildlife Fund), and FOAM are not primarily responsible for releasing lists of endangered species globally, although WWF does work extensively in wildlife conservation and might publish reports or statements regarding endangered species based on IUCN's Red List data.

Answer: D. Immigration (I) is not generally equal to emigration (E).

• Births (B) and deaths (D) are the primary factors determining population density (N) under normal conditions; immigration and emigration become important only in special situations.

• When a habitat is newly colonised, immigration (I) can be more important than natality (B) because individuals arriving from outside increase the population.

• B and I both increase N (positive contributions), while D and E decrease N (negative contributions).

• I equals E only at a dynamic equilibrium or in a perfectly closed and stable population; this is not generally true for most real populations, so the statement I is generally equal to E is incorrect.

Therefore, option D is incorrect.

In a marine aquatic ecosystem, the biomass of phytoplanktons (producers) is smaller than that of zooplanktons (primary consumers) and the biomass of zooplanktons is smaller than that of secondary consumers. This results in the inverted pyramid of biomass in an aquatic ecosystem. This shape is the consequence of the very short life spans of phytoplanktons, which are consumed almost as rapidly as they are formed. Also phytoplanktons have high reproductive potential, i.e., they reproduce rapidly.

Fossils are dead remains of plants and animals buried inside the earth crust millions of year ago. Fossils are commonly preserved in sedimentary rock as this kinds of rocks are formed layer by layer in course of time.

It is not adaptive radiation that confirms convergent evolution.

It is an adaptive convergence that confirms convergent evolution.

The remaining options are applicable to adaptive radiation.