BIOLOGY 3 Marks Question

1. Alexander Von Humboldt.  Within a region species, richness increased with increasing explored area but only up to a limit.
2.  

• The slopes of regression lines are the similar/unaffected distribution in an area/normal range.
• The slope of regression is steeper when we analyse the species-area relationship among very large areas like entire continent.

Z (slope of the line) regression co-efficient.

3. If species richness is more/0.62 - 1.2

1. Tropical latitude have remained relatively undisturbed, have a long evolutionary time for species diversification.
2. Less seasonal variations, constant and predictable environmental condition, promote niche specialization for greater species diversity.
3. More availability of solar energy, contributes to higher productivity.

1. To create awareness about disease and their effects on the body/about immunization/health and hygiene.
2.  

• Disposal of waste.
• Control of Vectors.
• Hygienic food and water/fresh drinking water/Balanced diet/Regular exercise/Yoga.

Parthenium/Lantana/Eichhornia invasive plants and pose a threat to indigenous species.

Introduction of African catfish (Clarias gariepinus) to aquaculture is a threat to Indian catfishes.

• Broadly utilitarian.
• Ecosystem services: Purify air, cycling of nutrients, habitat for wildlife, pollinating crops, aesthetic pleasure.
• Ethical.
• Philosophical/spiritual/moral duty towards future generations.

1. Ex - situ conservation.
2. Botanical garden, Wild life safaries, Cryopreservation, In-vitro, Seed bank, Tissue culture propagation.

1. Deforestation- Humans cut down trees to serve own purpose like construction of houses and roads. Which is the main cause of desertification.
2. Improper farming practices- If same crop is grown continuously makes the soil deficient of nutrients resulting in the loss of fertility of soil.
3. Soil Erosion- That is by different human activities like deforestation due to construction of houses and industrialisation.

1. Yes, India has greater ecosystem diversystem diversity than norway having deserts, rain forests, mangroves, coral reefs, wetlands, estuaries, and alphine meadows.
2. Genetic diversity:

1. Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species.
2. A single species might show high diversity at the genetic level (E.g. Man: Chinese, Indian American, African etc.) India has more than 50,000 genetically different strains of rice and 1,000 varieties of mango.
3. Genetic diversity allows species to adapt to changing environments. This diversity aims to ensure that some species survive drastic changes and thus carry on desirable genes.

Specific diversity:

1. It is the ratio of one species population over total number of organisms across all species in the given biome. ‘Zero’ would be infinite diversity, and ‘one’ represents only one species present.
2. Species diversity is a measure of the diversity within an ecological community that incorporates both species richness (the number of species in a community) and the eveness of species.
3. For example, the Western Ghats have a greater amphibian species diversity than the Eastern Ghats. There are more than 2,00,000 species in India of which several are confined to India (endemic).

1. Habitat loss and fragmentation.
2. Over exploitation.
3. Co-extinction.

1. The endangered organisms are protected from their exploitation and can be maintained in artificial habitats.
2. Their breeding programs can be regulated and the gametes, as well as embryos, can be preserved in viable and fertile conditions.
3. Seeds from different genetic strains can be made to undergo hybridization and can be kept for future experiments.
4. The health of individuals can be monitored and medical assistance can be given as required.
5. Modern reproductive technology can increase the chances of reproductive success.
6. Research into reproductive physiology, lifestyle, and ecology of an endangered species is made easier.

1. Species diversity decreases as one moves away from the equator towards poles.
2. In general tropics (latitudinal range of 23.5°N to 23.5°S) harbour more species than temperate or polar regions, because they have constant environments and more solar radiation.
3. e.g. Colombia located near the equator has about 1400 species of birds whereas New York (41°N) has only 105 species and Greenland (71°N) has only 56 species of birds.

1. Biodiversity should be conserved for the following reasons:

• The broadly utilitarian argument says that biodiversity plays a major role in many ecosystem services that nature provides.
• The narrow utilitarian argument says that humans derive countless direct economic benefits from nature and products of medicinal importance.
• The ethical argument for conserving biodiversity relates to what we owe to millions of plant, animal and microbe species with whom we share this planet.

2. Importance of biodiversity hotspots and sacred groves: Biodiversity hotspots are the regions of accelerated habitat loss. These can reduce the ongoing mass extinctions by almost 30%. Sacred groves are important in biodiversity conservation, as these are naturally protected by the native population without much effort. In Meghalaya, the sacred groves are the last refuges for large number of rare and threatened plants.

1. This is an apporach for in sin method of conservation. Eminent conservationists have identified certain regions for the maximum protection, these regions are called biodiversity hotspots.

These are regions with very high levels of species richness, high degree of endemism (species confined to a region and not found anywhere else) and accelerated habitat loss. Initially, 25 biodiversity hotspots were identified. Now, there are 34 hotspots all over the world.

These hotspots are in India, i.e. Western Ghats and Sri Lanka Indo-Burma and Eastern Himalaya. If all the biodiversity hotspots are put together, they cover less than 2% of the earth's land area, but harbor extremely high diversity. Ongoing mass extinctions could be reduced by 30% through strict protection of these hotspots.

2. There are two methods of conservation:

1. In Situ (On site) Conservation: It is the conservation and protection of the whole ecosystem and its biodiversity at all levels in order to protect the threatened species. However, it is not economically feasible to conserve all the biological wealth at all the existing ecosystems.

2. Ex-Situ (Off site) Conservation: This approach involves placing the threatened animals and plants in special care units for their protection. Ex-situ conservation includes off site collections and gene bank.

1. Practices that help to protect rare, threatened species are as follows:

• In-situ (onsite) conservation involves protection of species in their natural habitat. It involves biosphere reserves, national parks, wildlife sanctuaries, sacred groves, etc.
• Ex-situ (offsite) conservation involves placing of threatened animals and plants in special care units for their protection Zoological parks, botanical gardens and wildlife safari parks serve this purpose.

2. Commensalism because Ophrys employs sexual deceit to get pollinated by species of bee as petal of its flower bears resemblance to female of the bee in size, colour and marking and so, male bee is attracted to what it perceives as female; pseudocopulates with the flower and thus, pollinates it. If the female bee's colour patterns change even slightly due to any reason during evolution, pollination success will be reduced unless the orchid flowers co-evolves to maintain the resemblance of its petal to the female bee.

1. Because 20% of the total oxygen in the almosphere is produced by the plants of this forest.
2. The industrial products include:

1. Dyes.
2. Tannin.
3. Resins.
4. Lubricants.
5. Perfumes, etc.

1. The four major causes also called the Evil Quartet responsible for the loss of biodiversity are:

1. Habitat Loss and Fragmentation: Destruction of habitat is the most important causes of extinction of both plants and animals species, e.g. dui to habitat loss, 14% of the earth's land surface covered by tropical rainforest is now limited to only 60 loss in the last few years.

When large habitats are broken up into small fragments due to various human activities, mammals and birds requiring large territories and certain animals with migratory habits are badly affected, leading to their population declines.

2. Over-exploitation: Humans are always dependent on nature for food and shelter. But when human needs turn into greed, it leads to the degradation and extinction of natural resources Many species are extinct in last 500 years due ro over exploitation, e.g. Steller's sea cow, passenger pigeon, etc.

3. Alien species invasion: Introduction of alien species also causes the risk of extinction. When alien species are introduced, some of them turn invasive and cause decline or extinction of indigenous species, e.g. Nile perch, a large predator Fish, when introduced into the fake Victoria in East Africa, eventually led to the extinction of an ecologically unique assemblage of more than 200 species of cichlid fish in the lake.

Some well-known invasive weed species like Partbenium (carrot grass), Lantana and, water hyacinth (Eichhonia), had caused immense environmental damage and posed threar to our native species. The recent introduction of African catfish (Clarias gariepinus) illegally for aquaculture purpose is posing a threat to the indigenous catfishes of Indian rivers.

1. IUCN Red Data list: IUCN red list of threatened species is an inventory of global conservation status of biological species, which is compiled in Red Data Book. It was initiated in 1963. IUCN Red List (2004) enlists the extinction of 784 species (including 338 vertebrates, 359 invertebrates and 87 plant) in the last 500 years. The red list of 2012 contains 132 plant and animal species of India.

2. Hotspots in conservation of biodiversity: This is an apporach for in situ method of conservation. Eminent conservationists have identified certain regions for the maximum protection, these regions are called biodiversity hotspots.

These are regions with very high levels of species richness, high degree of endemism (species confined to a region and not found anywhere else) and accelerated habitat loss. Initially, 25 biodiversity hotspots were identified. Now, there are 34 hotspots all over the world.

1. The conventional taxonomic methods are not suitable/ sufficient for identifying these microbes.
2. Many of these cannot be cultured under laboratory conditions.
3. Biochemical and molecular biology techniques would put their diversity into millions.

Three other causes are:

1. Habitat Loss and Fragmentation: Destruction of habitat is the most important causes of extinction of both plants and animals species, e.g. dui to habitat loss, 14% of the earth's land surface covered by tropical rainforest is now limited to only 60% loss in the last few years.

When large habitats are broken up into small fragments due to various human activities, mammals and birds requiring large territories and certain animals with migratory habits are badly affected, leading to their population declines.

2. Over-exploitation: Humans are always dependent on nature for food and shelter. But when human needs turn into greed, it leads to the degradation and extinction of natural resources Many species are extinct in last 500 years due ro over exploitation, e.g. Steller's sea cow, passenger pigeon, etc.

3. Alien species invasion: Introduction of alien species also causes the risk of extinction. When alien species are introduced, some of them turn invasive and cause decline or extinction of indigenous species, e.g. Nile perch, a large predator Fish, when introduced into the fake Victoria in East Africa, eventually led to the extinction of an ecologically unique assemblage of more than 200 species of cichlid fish in the lake.

Some well-known invasive weed species like Partbenium (carrot grass), Lantana and, water hyacinth (Eichhonia), had caused immense environmental damage and posed threar to our native species. The recent introduction of African catfish (Clarias gariepinus) illegally for aquaculture purpose is posing a threat to the indigenous catfishes of Indian rivers.

1. Species diversity and species density.
2. Degree of endemism.
3. Degree of threat due to degradation, habitat loss.
4. Degree of exploitation.

Uses:

1. Identification and documentation of endangered species.
2. Creating awareness about importance of threatened biodiversity.

1. Low Latitude: Biodiversity is higher in lower latitudes than in higher latitudes.
   
2. Presence of rainforests and deciduous forests.
   
3. Presence of mountain forests.
   

• Genetic diversity: It is the genetic variability among a species.
• Species diversity: It refers to the number of species that live in a particular place.
• Ecological diversity: It refers to the variation in ecosystems in a particular region or variation in ecosystem across the planet.

• Habitat loss and fragmentation: Habitats of various organisms are altered or destroyed by uncontrolled and unsustainable human activities such as deforestation, slash and burn agriculture, mining, and urbanization. This results in the breaking up of the habitat into small pieces, which effects the movement of migratory animals and also, decreases the genetic exchange between populations leading to a declination of species.
  
• Over-exploitation: Due to over-hunting and over-exploitation of various plants and animals by humans, many species have become endangered or extinct (such as the tiger and the passenger pigeon).
  
• Alien species Invasions: Accidental or intentional introduction of non- native species into a habitat has also led to the declination or extinction of indigenous species. For example, the Nile perch introduced in Lake Victoria in Kenya led to the extinction of more than two hundred species of native fish in the lake.
  
• Co-extinction: In a native habitat, one species is connected to the other in an intricate network. The extinction of one species causes the extinction of other species, which is associated with it in an obligatory way. For example, the extinction of the host will cause the extinction of its parasites.
  

1. It shall not show too much variation in the year-to-year productivity.
2. It must be either resistant or resilient to seasonal disturbances.
3. It must be resistant to invasion of alien species.

1. We get food, medicines, raw materials, wood, etc. from nature and this is possible become of biodiversity.
2. Biodiversity helps in maintaining the ecosystem. A healthy ecosystem is beneficial for all of us.

1. Conserved species can be used to restore degraded land, reintroduce species into wild and restock depleted populations.
2. It provides breeders and genetic engineers with a ready source of genetic material.