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Value, threats, the Red List and conservation

తెలుగులో వివరణ

Biodiversity · Part 2 / 2 · Fact-checked on 8 November 2026 · how we check

Written with AI from the sources listed at the bottom of this page, then fact-checked by a separate AI.

Direct values and ecosystem services; the rivet popper hypothesis; the evil quartet of threats; background and mass extinctions; the IUCN Red List and its categories; in situ and ex situ conservation, sacred groves, seed and gene banks; India's biodiversity institutions.

Each idea is explained first in Telugu (తెలుగు), ending with the English and Hindi exam terms, followed by the same point in exam English. UPSC Prelims is in English or Hindi, so understand it in Telugu and revise it in English.

మొదటి భాగంలో జీవం ఎక్కడ ఎక్కువగా ఉందో చూశాం. ఇప్పుడు మూడు ప్రశ్నలు: ఈ సంపద ఎందుకు ముఖ్యం, దాన్ని ఏది నాశనం చేస్తోంది, ఎలా కాపాడుతున్నాం. ఇంట్లో బంగారం ఉంటే దాని విలువ తెలుసుకుంటాం, దొంగల భయం గుర్తిస్తాం, తాళం వేస్తాం కదా, అలాగే. ఏ జాతి ఎంత ప్రమాదంలో ఉందో ఐయూసీఎన్ రెడ్ లిస్ట్ చెబుతుంది. (→ English: IUCN Red List · हिन्दी: आईयूसीएन रेड लिस्ट)

In exam EnglishPart 1 showed where life is richest. This part asks why that richness matters, what is destroying it and how it is protected. It runs in a line: the value of biodiversity, including the services ecosystems perform for free; the forces that push species towards extinction and the record of past extinctions; the IUCN Red List that measures the danger; and the two families of conservation, protecting life where it lives and saving it elsewhere, with the Indian institutions that do this work.

మనం ప్రకృతి నుంచి నేరుగా తీసుకునేవి: ఆహారం, మందులు, కలప, తేనె, చేపలు. ఈ రోజు పొలంలో పండే వరి ఒకప్పుడు అడవి మొక్కే. జ్వరానికి వాడిన క్వినైన్ సింకోనా చెట్టు బెరడు నుంచి వచ్చింది; మన పెరట్లో పెరిగే బిళ్ళగన్నేరు (సదాబహార్) లాంటి మొక్క నుంచి క్యాన్సర్ మందులు వస్తాయి. అడవిని ఒక పెద్ద మందుల దుకాణం అనుకోండి, ఇంకా తెరవని అరలు ఎన్నో ఉన్నాయి. (→ English: direct value; bioprospecting · हिन्दी: प्रत्यक्ष मूल्य; जैव पूर्वेक्षण)

In exam EnglishThe plainest value of biodiversity is what people take from it directly. Every crop and farm animal was once wild, and the wild relatives of crops still carry genes for resisting pests, drought and disease. Many medicines started as chemicals made by plants. Quinine, long the main drug against malaria, came from the bark of the cinchona tree; aspirin traces its origin to salicin, a compound in willow bark; and the Madagascar periwinkle is the plant source of vincristine and vinblastine, two drugs used to treat cancer. Searching living things for new drugs, genes and products is called bioprospecting, and species-rich countries have demanded a fair share of the gains, a principle the Convention on Biological Diversity accepts. Timber, fibre, fuelwood, honey, resins and fish complete the list, and many forest and coastal communities in India live on them.

కంటికి కనపడకుండా ప్రకృతి చేసే పనులే పర్యావరణ వ్యవస్థ సేవలు. ఊరి చెరువు ఊహించండి: నీళ్ళు ఇస్తుంది (సరఫరా), వరద నీటిని పట్టుకుంటుంది (నియంత్రణ), పండుగ రోజు అక్కడే స్నానం, పూజ (సాంస్కృతిక), లోపల మట్టి, పోషకాలు తిరుగుతూనే ఉంటాయి (సహాయక). దీనికి ఎవరూ బిల్లు పంపరు, కానీ పోతే మనమే లక్షలు ఖర్చు పెట్టాలి. (→ English: ecosystem services · हिन्दी: पारिस्थितिकी तंत्र सेवाएँ)

In exam EnglishLess visible, and far larger in value, is the work ecosystems do without being asked. These benefits are called ecosystem services. The Millennium Ecosystem Assessment, a global study backed by the United Nations and published in 2005, sorted them into four groups. Provisioning services are the goods themselves: food, fresh water, wood and medicine. Regulating services keep conditions stable: forests hold soil and soften floods, wetlands filter water, mangroves absorb storm surges and insects pollinate crops. Cultural services are the spiritual, recreational and aesthetic meaning people find in nature, from a sacred grove to a tiger safari. Supporting services such as soil formation, nutrient cycling and photosynthesis underlie all the rest. Beside these uses stands an ethical argument: each species is the result of a long evolutionary history, and many hold that humans have no right to end it.

ఒక పాత మంచం ఊహించండి: నవారు నుంచి ఒక్కో దారం లాగుతూ పోతే మొదట ఏమీ తెలియదు, ఒక రోజు ఒక్కసారిగా కూలిపోతుంది. మూల కాలు ఊడితే మాత్రం వెంటనే పడిపోతుంది. అడవిలో ప్రతి జాతి ఒక దారం; కీస్టోన్ జాతి ఆ మూల కాలు. ఎన్ని ఎక్కువ జాతులు ఉంటే, అంత బలంగా, స్థిరంగా ఉంటుంది. (→ English: rivet popper hypothesis; keystone species · हिन्दी: रिवेट पॉपर परिकल्पना; कीस्टोन प्रजाति)

In exam EnglishDoes it matter if a few species vanish from a rich ecosystem? The Stanford ecologist Paul Ehrlich answered with an image. Think of the many thousands of rivets that fasten an aircraft together. Removing them one by one might cause no visible trouble for a while, but sooner or later the aircraft becomes unsafe to fly, and losing a rivet that holds a wing matters far more than losing several from a passenger seat. Each lost species likewise weakens an ecosystem a little, and the loss of a keystone species can bring on a collapse. This is the rivet popper hypothesis. Experiments back the broad idea: in long-running grassland plots in Minnesota, the American ecologist David Tilman found that plots with more species showed smaller swings in total plant growth from year to year. Diversity works like insurance for an ecosystem.

జాతులు అంతరించడానికి నాలుగు పెద్ద కారణాలు. ఇల్లు కూల్చితే (అడవి నరకడం) లేదా ఇంటిని ముక్కలు చేస్తే ఏనుగులాంటి పెద్ద జంతువుకు చోటు సరిపోదు. బావిలో నీళ్ళు ఊరే దానికంటే వేగంగా తోడితే బావి ఎండిపోతుంది, అదే అతిగా వేటాడటం. బయటి నుంచి వచ్చిన వయ్యారిభామ (పార్థేనియం), గుర్రపుడెక్క లాంటి ఆక్రమణ జాతులు మన మొక్కలను అణచేస్తాయి. ఒక జాతి పోతే దాని మీద ఆధారపడినవీ పోతాయి. (→ English: evil quartet; habitat fragmentation; invasive species; co-extinction · हिन्दी: दुष्ट चौकड़ी; आवास विखंडन; आक्रामक प्रजाति; सह-विलोपन)

In exam EnglishThe geographer and biologist Jared Diamond grouped the chief causes of extinction into an 'evil quartet'. First and worst is habitat loss and fragmentation: clearing a forest or draining a wetland removes homes outright, and cutting a large habitat into small patches hurts most the animals that need wide ranges, such as elephants and tigers. Second is overexploitation, harvesting faster than a population can recover; Steller's sea cow was hunted out within about thirty years of its discovery, and the passenger pigeon, once abundant across North America, ended with the death of the last bird in a zoo in 1914. Third come invasive species: after the Nile perch was introduced into Lake Victoria, a large number of the lake's native cichlid species disappeared, and in India lantana, parthenium and water hyacinth smother native plants. Fourth is co-extinction, where a species takes its dependants with it, such as its own parasites or a plant served by a single pollinator. Pollution and climate change now add to all four.

జాతులు నెమ్మదిగా పోవడం, కొత్తవి రావడం సహజమే, ఊళ్ళో పెద్దవాళ్ళు పోయి పిల్లలు పుట్టినట్టు. కానీ ఐదుసార్లు పెద్ద ఉపద్రవం వచ్చి చాలా జాతులు ఒకేసారి పోయాయి; ఇదే సామూహిక వినాశనం. చివరిది 6.6 కోట్ల సంవత్సరాల క్రితం, డైనోసార్లు పోయినప్పుడు. ఇప్పుడు ఆరోసారి జరుగుతోందని శాస్త్రవేత్తలు అంటున్నారు, ఈసారి కారణం మనుషులే. మన దేశంలో చీతా 1952లో కనుమరుగైంది. (→ English: background extinction; mass extinction · हिन्दी: पृष्ठभूमि विलोपन; सामूहिक विलोपन)

In exam EnglishExtinction in itself is natural. Species have always disappeared at a slow background rate as conditions shifted, while new ones arose. Five times, though, extinction has swept away a large share of all species within a short span of geological time; these are the five mass extinction events. The largest closed the Permian period about 252 million years ago, when most marine species died out. The best known, about 66 million years ago at the end of the Cretaceous, ended the non-bird dinosaurs and is tied to an asteroid impact. Many scientists now describe a sixth mass extinction under way, caused this time by a single species, our own. The 2019 global assessment of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) estimated that about one million animal and plant species face extinction, many within decades. India's own loss is the cheetah, declared extinct in the country in 1952; cheetahs from Namibia were released in Kuno National Park, Madhya Pradesh, in September 2022.

The five mass extinctions
Event	About how long ago	What stands out
End-Ordovician	444 million years	Mostly marine life; linked to glaciation
Late Devonian	372 million years	Reef-building life hit hard
End-Permian	252 million years	The largest; most marine species lost
End-Triassic	201 million years	Opened the way for the dinosaurs
End-Cretaceous	66 million years	Non-bird dinosaurs ended; asteroid impact

ఆసుపత్రిలో రోగులను పరిస్థితిని బట్టి వార్డుల్లో పెట్టినట్టు, ఐయూసీఎన్ రెడ్ లిస్ట్ జాతులను వర్గాలుగా పెడుతుంది: ఐసీయూలో ఉన్నవి (తీవ్ర అపాయం), సీరియస్ (అపాయం), జాగ్రత్త కావాలి (దుర్బలం). బట్టమేక పక్షి, ఘరియాల్ ఐసీయూలో; పులి సీరియస్; ఒంటికొమ్ము ఖడ్గమృగం జాగ్రత్తలో. ఇది డాక్టర్ రిపోర్ట్ మాత్రమే, చట్టం కాదు; మన దేశంలో చట్టపరమైన రక్షణ 1972 వన్యప్రాణి చట్టం ఇస్తుంది. (→ English: IUCN Red List; Critically Endangered; Endangered; Vulnerable · हिन्दी: आईयूसीएन रेड लिस्ट; गंभीर रूप से संकटग्रस्त; संकटग्रस्त; सुभेद्य)

In exam EnglishHow close a species stands to extinction is judged by the IUCN Red List of Threatened Species, maintained by the International Union for Conservation of Nature. Founded in 1948, with its headquarters at Gland in Switzerland, the IUCN is unusual in having both governments and non-governmental organisations as members. The Red List, begun in 1964, assigns each assessed species to one of nine categories using measurable tests, such as the speed of population decline, the size of the range and the number of mature individuals left. Only three categories, Critically Endangered, Endangered and Vulnerable, are counted as 'threatened'. Indian examples fix the scale: the great Indian bustard and the gharial are Critically Endangered, the tiger is Endangered and the greater one-horned rhinoceros is Vulnerable. The list is a scientific assessment and has no legal force; in India, legal protection comes from the schedules of the Wild Life (Protection) Act, 1972.

IUCN Red List categories, from most to least at risk
Code	Category	Meaning
EX	Extinct	No reasonable doubt the last individual has died
EW	Extinct in the Wild	Survives only in captivity or cultivation
CR	Critically Endangered	Extremely high risk of extinction in the wild (threatened)
EN	Endangered	Very high risk (threatened)
VU	Vulnerable	High risk (threatened)
NT	Near Threatened	Close to qualifying for a threatened category
LC	Least Concern	Widespread and abundant
DD	Data Deficient	Too little information to judge
NE	Not Evaluated	Not yet assessed

స్వస్థానే సంరక్షణ అంటే జంతువును దాని సొంత ఇంట్లోనే, అంటే అడవిలోనే కాపాడటం; ఇల్లు, ఇరుగుపొరుగు అంతా కలిపి రక్షించడం. చట్టం రాకముందే మన ఊళ్ళు ఇది చేశాయి: దేవుడి పేరుతో వదిలేసిన పవిత్ర వనం లో ఎవరూ చెట్టు నరకరు, అందుకే అక్కడ పాత చెట్లు, అరుదైన మొక్కలు ఇంకా ఉన్నాయి. రాజస్థాన్ బిష్ణోయిలు ఖేజ్రీ చెట్ల కోసం ప్రాణాలే ఇచ్చారు. (→ English: in situ conservation; sacred grove · हिन्दी: स्वस्थाने संरक्षण; पवित्र उपवन)

In exam Englishin situ conservation means protecting species in their natural homes, together with the ecosystems they depend on. It is generally preferred because it saves whole communities at once and lets species go on evolving in natural conditions. In India its main legal form is the network of protected areas, national parks, wildlife sanctuaries, conservation reserves and community reserves, along with tiger reserves and biosphere reserves, which the next chapter covers. But in situ conservation is older than any statute. All over India, communities have left patches of forest untouched as sacred groves dedicated to a local deity: they go by many local names, for example kavu in Kerala, devrai in Maharashtra, law kyntang in Meghalaya and sarna in Jharkhand, and many still hold old trees and rare plants lost from the land around them. The Bishnoi community of Rajasthan guards khejri trees and blackbuck; in 1730 Amrita Devi and many others of the community were killed at Khejarli while resisting the felling of khejri trees.

పరస్థానే సంరక్షణ అంటే జాతిని దాని ఇంటి బయట, జూలో, తోటలో, బ్యాంకులో కాపాడటం. ఇంట్లో అందరికీ జబ్బు వస్తే పిల్లల్ని కొన్నాళ్ళు బంధువుల ఇంటికి పంపినట్టు. రైతు మంచి విత్తనాలను వచ్చే ఏడాదికి గాదెలో దాచినట్టే, జన్యు బ్యాంకు విత్తనాలను చల్లగా దాచి ఉంచుతుంది. డైక్లోఫెనాక్ మందు వల్ల రాబందులు తగ్గాక పింజోర్‌లో వాటిని పెంచుతున్నారు. (→ English: ex situ conservation; gene bank; cryopreservation · हिन्दी: परस्थाने संरक्षण; जीन बैंक; क्रायोसंरक्षण)

In exam Englishex situ conservation means keeping species alive outside their natural habitat, usually because the wild population is too small or too threatened to last on its own. Zoos, botanical gardens and safari parks hold living animals and plants, and captive breeding can raise numbers for release. India's vulture breeding centre at Pinjore in Haryana was started after three Gyps vulture species crashed, poisoned by the painkiller diclofenac in the carcasses of treated cattle. For plants and genetic material, storage is the main tool. Seed banks keep dried seeds cold for decades; field gene banks grow living collections of crops that cannot be kept as seed; and cryopreservation holds sperm, eggs, embryos, pollen or tissue in liquid nitrogen at about minus 196 °C. The National Bureau of Plant Genetic Resources (NBPGR) in New Delhi runs India's national gene bank. Globally, the Svalbard Global Seed Vault, cut into a mountain on a Norwegian Arctic island and opened in 2008, keeps back-up copies of seed from gene banks worldwide.

ఇంట్లో ఆస్తి ఎంత ఉందో తెలియాలంటే లెక్కల పుస్తకం కావాలి. మొక్కల లెక్క భారత వృక్షశాస్త్ర సర్వే (1890), జంతువుల లెక్క భారత జంతుశాస్త్ర సర్వే (1916) రాస్తాయి, రెండూ కోల్‌కతాలో. చట్టం ప్రకారం మూడు అంచెలు: పైన చెన్నైలో జాతీయ సంస్థ, మధ్యలో రాష్ట్ర బోర్డు, కింద ఊరి కమిటీ, అది ఊరి మొక్కలు, జంతువులు, పెద్దల జ్ఞానం ఒక రిజిస్టర్‌లో రాస్తుంది. (→ English: Botanical Survey of India; Zoological Survey of India; National Biodiversity Authority; People's Biodiversity Register · हिन्दी: भारतीय वनस्पति सर्वेक्षण; भारतीय प्राणि सर्वेक्षण; राष्ट्रीय जैव विविधता प्राधिकरण; लोक जैव विविधता रजिस्टर)

In exam EnglishWhat India knows about its living wealth rests largely on two old survey bodies. The Botanical Survey of India, set up in 1890, explores and documents the country's plants, and the Zoological Survey of India, founded in 1916, does the same for animals; both are headquartered in Kolkata and publish the official counts of Indian flora and fauna. The Wildlife Institute of India at Dehradun, established in 1982, trains wildlife managers and conducts research. To carry out India's duties under the Convention on Biological Diversity, Parliament passed the Biological Diversity Act, 2002. It created three tiers: the National Biodiversity Authority, set up in 2003 and based in Chennai; State Biodiversity Boards; and Biodiversity Management Committees in local bodies, which prepare People's Biodiversity Registers recording local species and traditional knowledge.

మొత్తం మూడు ప్రశ్నలు: ఎందుకు కాపాడాలి (ఆహారం, మందులు, ఉచిత సేవలు, స్థిరత్వం), దేనివల్ల ప్రమాదం (ఇల్లు పోవడం, అతి వేట, బయటి జాతులు, ఒకటి పోతే మరొకటి), ఎలా కాపాడాలి (ఐయూసీఎన్ రెడ్ లిస్ట్ తో ప్రమాదం కొలవడం, ఇంట్లోనే రక్షణ, బయట బ్యాకప్). జూలో పెంచిన రాబందుకు తిరిగి వెళ్ళడానికి సురక్షితమైన ఆకాశం లేకపోతే లాభం లేదు, రెండూ కలిసి పని చేయాలి. (→ English: in situ and ex situ conservation; IUCN Red List · हिन्दी: स्वस्थाने और परस्थाने संरक्षण; आईयूसीएन रेड लिस्ट)

In exam EnglishThe part answers three linked questions. Why save biodiversity? Because it feeds and heals people, its services are worth far more than its goods, and, like rivets in an aeroplane, each species steadies the whole. What threatens it? The evil quartet, now joined by pollution and climate change, driving what many call a sixth mass extinction. How is it protected? The IUCN Red List measures the risk; in situ conservation guards species in their homes through protected areas and community traditions such as sacred groves; ex situ conservation keeps a reserve in zoos, gardens, seed and gene banks. The two approaches complement each other: a vulture bred in captivity is of little use without safe skies and carcasses free of poison to return to.

Exam traps

Jared Diamond's 'evil quartet' has four members: the loss and breaking-up of habitats, over-harvesting, alien invaders (invasive species) and CO-EXTINCTION. Pollution and climate change are serious but are not among the original four.
The rivet popper image comes from Paul EHRLICH; the long-term grassland plots of David Tilman supplied the evidence that species-rich plots are more stable in productivity.
Only CR, EN and VU are 'threatened' categories. Near Threatened, Least Concern and Data Deficient are NOT threatened.
Extinct in the Wild (EW) is not Extinct (EX): an EW species still survives in captivity or cultivation.
The IUCN Red List has NO legal force; legal protection in India comes from the Wild Life (Protection) Act, 1972. IUCN is headquartered at Gland, Switzerland, not Geneva.
IN SITU means inside the natural habitat: sacred groves, national parks, biosphere reserves. EX SITU means outside it: zoos, botanical gardens, seed and gene banks, and cryopreservation.
The largest mass extinction was the END-PERMIAN (about 252 million years ago), not the end-Cretaceous that ended the dinosaurs.
India's national gene bank is run by the NBPGR, New Delhi; the Svalbard Global Seed Vault is in NORWAY.

Recap

Direct values: food, medicine (quinine, aspirin's origin in willow, vincristine from periwinkle), fibre, timber; bioprospecting.
Ecosystem services (Millennium Ecosystem Assessment, 2005): provisioning, regulating, cultural, supporting.
Rivet popper hypothesis (Paul Ehrlich): each lost species weakens the ecosystem; Tilman showed diversity stabilises productivity.
Evil quartet (Jared Diamond): habitat loss and fragmentation, overexploitation, invasive species, co-extinction.
Five mass extinctions; the end-Permian (about 252 million years ago) was the largest; many speak of a sixth, caused by humans (IPBES 2019: about one million species at risk).
Cheetah declared extinct in India in 1952; cheetahs from Namibia released in Kuno National Park in September 2022.
IUCN (1948, Gland); Red List (1964); nine categories; CR, EN and VU are threatened; no legal force.
In situ: protected areas, sacred groves (devrai, kavu, sarna, law kyntang), Bishnoi tradition. Ex situ: zoos, gardens, captive breeding (Pinjore vultures), seed and gene banks, cryopreservation at about minus 196 °C.
NBPGR runs the national gene bank; Svalbard Global Seed Vault (Norway, 2008).
BSI (1890) and ZSI (1916), both Kolkata; WII Dehradun (1982); NBA Chennai (2003), State Biodiversity Boards, BMCs and People's Biodiversity Registers.

Practice questions

Q1. Which one of the following is NOT one of the four causes of extinction grouped by Jared Diamond as the 'evil quartet'?

Habitat loss and fragmentation
Co-extinction
Climate change
Invasive alien species

Show answer

Answer: C. Climate change

The evil quartet is habitat loss and fragmentation, overexploitation, invasive species and co-extinction, so options 1, 2 and 4 are part of it. Climate change is now a major threat but was not one of Diamond's original four.

Q2. Consider the following IUCN Red List categories:
1. Vulnerable
2. Near Threatened
3. Endangered
4. Data Deficient
Which of the above are counted as 'threatened' categories?

1 and 3 only
1, 2 and 3 only
2 and 4 only
1, 2, 3 and 4

Show answer

Answer: A. 1 and 3 only

Only Critically Endangered, Endangered and Vulnerable are threatened, so of these only 1 and 3. Near Threatened is close to, but outside, the threatened group, which rules out options 2 and 4; Data Deficient means there is too little information to place the species, which rules out options 3 and 4.

Q3. Which of the following is an example of in situ conservation?

A seed bank
A sacred grove
Cryopreservation of embryos
A botanical garden

Show answer

Answer: B. A sacred grove

A sacred grove protects species in their natural habitat, which is in situ. A seed bank, cryopreservation and a botanical garden all keep species or their genetic material outside the natural habitat, so they are ex situ.

Q4. Consider the following statements:
1. The IUCN Red List is legally binding on member countries.
2. The IUCN has both governments and non-governmental organisations as its members.
Which of the statements given above is/are correct?

1 only
2 only
Both 1 and 2
Neither 1 nor 2

Show answer

Answer: B. 2 only

Statement 1 is wrong: the Red List is a scientific assessment with no legal force, so options 1 and 3 fail. Statement 2 is right, so option 4 fails as well.

Q5. The 'rivet popper hypothesis', which compares species in an ecosystem to rivets in an aeroplane, was put forward by

Norman Myers
Paul Ehrlich
Robert Whittaker
Alexander von Humboldt

Show answer

Answer: B. Paul Ehrlich

Paul Ehrlich proposed the rivet popper hypothesis. Norman Myers proposed biodiversity hotspots, Robert Whittaker the alpha, beta and gamma measures of diversity, and Humboldt is linked with the species–area relationship.

Q6. Match List I with List II:
List I (Body) — List II (Headquarters)
A. Botanical Survey of India — 1. Chennai
B. National Biodiversity Authority — 2. Dehradun
C. Wildlife Institute of India — 3. Kolkata
Select the correct answer using the code below.

A-3, B-1, C-2
A-1, B-3, C-2
A-3, B-2, C-1
A-2, B-1, C-3

Show answer

Answer: A. A-3, B-1, C-2

BSI is in Kolkata, the NBA in Chennai and WII in Dehradun, giving A-3, B-1, C-2. Option 2 puts BSI in Chennai, option 3 swaps the NBA and WII, and option 4 puts BSI in Dehradun and WII in Kolkata.

Q7. Consider the following statements:
1. The largest of the five mass extinctions occurred at the end of the Cretaceous period.
2. The cheetah was declared extinct in India in 1952.
Which of the statements given above is/are correct?

1 only
2 only
Both 1 and 2
Neither 1 nor 2

Show answer

Answer: B. 2 only

Statement 1 is wrong: the largest was the end-Permian, about 252 million years ago; the end-Cretaceous is the best known because it ended the non-bird dinosaurs. That rules out options 1 and 3. Statement 2 is correct, which rules out option 4.

Q8. In ex situ conservation, cryopreservation of sperm, embryos or tissue is usually done in

Liquid nitrogen at about minus 196 °C
Dry ice at about minus 78 °C
An ordinary refrigerator at about 4 °C
Liquid oxygen at about minus 100 °C

Show answer

Answer: A. Liquid nitrogen at about minus 196 °C

Cryopreservation uses liquid nitrogen at about minus 196 °C. Dry ice is far less cold and used for transport, a refrigerator only slows decay for a short time, and liquid oxygen is neither used for this nor liquid at minus 100 °C.

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Sources

Ministry of Environment, Forest and Climate Change: India's national reports to the Convention on Biological Diversity and the National Biodiversity Action Plan; Botanical Survey of India and Zoological Survey of India material on India's flora, fauna and endemism — https://moef.gov.in
Convention on Biological Diversity, 1992 (text), and the Biological Diversity Act, 2002 — https://www.cbd.int/convention/text
Ministry of Environment, Forest and Climate Change: National Wildlife Action Plan and material on threatened species and the Wild Life (Protection) Act, 1972 — https://moef.gov.in
Millennium Ecosystem Assessment (2005), Ecosystems and Human Well-being: categories of ecosystem services and drivers of biodiversity change — https://www.millenniumassessment.org
IUCN Red List of Threatened Species: categories and criteria; IPBES Global Assessment Report on Biodiversity and Ecosystem Services (2019) — https://www.iucnredlist.org
ICAR-National Bureau of Plant Genetic Resources: the National Genebank, seed storage, field genebanks and cryopreservation — https://nbpgr.ernet.in