Answer:
Introduction:
Hot spots are regions that have a high concentration of biodiversity and are under threat from human activities. India is known for its rich biodiversity, and it is important to protect these regions to preserve the unique flora and fauna.

To determine the number of hot spots covering India's high biodiversity regions, we need to consider the available options.
Options:
A: 25
B: 3
C: 34
D: 2
Explanation:
The correct answer is option B: 3. There are three hot spots that cover India's high biodiversity regions. These hot spots are:
1. Western Ghats: The Western Ghats is a mountain range along the western coast of India, known for its high biological diversity. It is considered one of the eight hottest hot spots in the world.
2. Eastern Himalayas: The Eastern Himalayas is another hot spot in India. This region is home to a wide range of plant and animal species, including many endemic species.
3. Indo-Burma region: The Indo-Burma region, which includes parts of northeastern India, is also considered a hot spot due to its high biodiversity.
These three hot spots cover India's high biodiversity regions and are crucial for the conservation of its unique ecosystems.
Conclusion:
In conclusion, India has three hot spots that cover its high biodiversity regions. These hot spots are the Western Ghats, Eastern Himalayas, and Indo-Burma region. Protecting these areas is essential for the preservation of India's rich flora and fauna.

Explanation:
The correct answer is D, both (1) and (3). Here is a detailed explanation:
Steller's cow:
- Steller's cow, also known as the Steller's sea cow, was a large marine mammal that inhabited the North Pacific Ocean.
- It was discovered by explorers in the 18th century, but due to overhunting for its meat and hide, it became extinct by the end of the 18th century.
- This overexploitation by humans led to the extinction of Steller's cow.
Passenger pigeon:
- The passenger pigeon was once one of the most abundant bird species in North America.
- However, due to overhunting and habitat destruction, its population declined rapidly in the late 19th century.
- The last known passenger pigeon died in captivity in 1914, making it extinct.
- Overexploitation by humans played a significant role in the extinction of the passenger pigeon.
Lantana:
- Lantana is a genus of flowering plants that is native to tropical regions.
- While Lantana itself is not extinct, overexploitation and habitat destruction have led to the extinction of certain species within the genus.
- However, the question does not specifically mention any species of Lantana being extinct.
Therefore, the correct answer is D, both (1) and (3), as both Steller's cow and the passenger pigeon have become extinct due to overexploitation by humans.

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 evenness of species abundances and it varies from region to region and mainly depends on rainfall apart from other other factors like temperature, light intensity etc. 

The 'Red Data Book 'is the state document which is established for documenting rare and endangered species of animals, plants and fungi as well as some local subspecies that exist within the territory of the state or country. This book provides essential information for studies and monitoring programmes on rare and endangered species and their habits. 

Answer:
The Green book contains suggestions for sustainable development. Here is a detailed explanation:
List of Contents:
- The list of endangered plants
- The list of extinct plants
- Suggestions for sustainable development
- Flora of a certain area
Explanation:
- The list of endangered plants: The Green book may include information about plants that are at risk of extinction or are currently classified as endangered. This list helps raise awareness about the importance of preserving these plants and taking measures to protect them.
- The list of extinct plants: The Green book may also provide information on plants that have become extinct. This list serves as a reminder of the consequences of not preserving our natural resources and highlights the importance of conservation efforts.
- Suggestions for sustainable development: One of the main purposes of the Green book is to provide suggestions and guidelines for sustainable development. It may include strategies and practices that individuals, communities, and organizations can adopt to promote environmental sustainability while meeting their developmental needs.
- Flora of a certain area: The Green book may contain detailed information about the flora of a specific region or area. It may include descriptions, photographs, and other relevant information about the plants found in that particular area.
In conclusion, the Green book primarily focuses on providing suggestions for sustainable development. However, it may also include information about endangered and extinct plants as well as the flora of a certain area.

Dioscorea is considered an endangered plant due to overexploitation.  This is a medicinal plant from the Himalayan region and it produces bulbil and rhizome and it is rich in steroidal compounds . Maize, Wheat, and rice are not used for medicinal purposes.

Plant species of medicinal value that is endangered:

1. Butea frondosa: This plant species is not mentioned in the given options, so it is not the correct answer.


2. Rauwolfia serpentina: This plant species is mentioned in option B. It is commonly known as Indian snakeroot and is used in traditional medicine for treating various ailments. Due to extensive harvesting and habitat loss, Rauwolfia serpentina is now considered endangered.


3. Cocus nucifera: This plant species is mentioned in option C. It is commonly known as the coconut tree and is not considered endangered. It is widely cultivated for its fruit and other uses.


4. Mangifera land slides: This plant species is mentioned in option D. However, the name seems to be incorrect or misspelled. It is not a recognized plant species, so it is not the correct answer.


 

Ex situ conservation refers to the conservation of endangered plant species outside of their natural habitat, typically in a botanical garden or in controlled circumstances. Here is a detailed explanation of ex situ conservation and why it is an effective method for conserving endangered plant species:
What is Ex Situ Conservation?
Ex situ conservation involves the removal and relocation of endangered plant species from their natural habitats to a controlled environment. This can be done in botanical gardens, seed banks, or other dedicated facilities. The goal is to ensure the survival and reproduction of these plants while protecting them from threats they may face in the wild.
Advantages of Ex Situ Conservation:
1. Protection from threats: By bringing endangered plant species into controlled environments, they are protected from various threats such as habitat destruction, climate change, and invasive species.
2. Research and education: Ex situ conservation allows scientists and researchers to study and understand endangered plant species better. It also provides educational opportunities for the public to learn about the importance of biodiversity and conservation.
3. Species recovery: In some cases, ex situ conservation can help in the recovery and reintroduction of endangered plant species back into their natural habitats. This can contribute to the restoration of ecosystems and the overall conservation of biodiversity.
4. Genetic diversity preservation: Ex situ conservation often involves the collection and preservation of seeds, tissue samples, or living plants. This helps preserve the genetic diversity of endangered plant species, which is crucial for their long-term survival and adaptation to changing environments.
Methods of Ex Situ Conservation:
1. Botanical gardens: These are dedicated facilities where endangered plant species are grown and maintained under controlled conditions. They provide a suitable environment for the plants to thrive and reproduce.
2. Seed banks: Seed banks collect, store, and preserve seeds of endangered plant species. These seeds can be used for future research, restoration projects, or reintroduction efforts.
3. Tissue culture: Tissue culture involves the growth of plant cells or tissues in a laboratory setting. This method allows for rapid multiplication of endangered plant species and can be used to produce large numbers of plants for conservation purposes.
4. Cryopreservation: Cryopreservation involves the freezing and storage of plant seeds, embryos, or tissues at extremely low temperatures. This method allows for long-term preservation of genetic material and is particularly useful for species with recalcitrant seeds or for long-term storage.
In conclusion, ex situ conservation is an effective method for conserving endangered plant species. It provides protection, research opportunities, and the potential for species recovery. Various methods such as botanical gardens, seed banks, tissue culture, and cryopreservation are employed to ensure the survival and future of these plant species.

Extinction is the end of an organism or of a group of organisms, normally a species. Humans cause extinction of a species through over harvesting, pollution, habitat destruction, invasion of invasive species, over hunting and other influences. Although, earthquakes and diseases are the results of human activities but it does not cause any extinction of plant species. 

Therefore, the correct answer is option B.

The main aim of plant conservation is:
There are two main aims of plant conservation:
A: To conserve the necessary ecological activities and life supporting systems
- Plant conservation plays a crucial role in maintaining the balance of ecosystems and the overall health of the environment.
- Plants are essential for providing oxygen, regulating climate, purifying water, and supporting various animal species.
- By conserving plants, we ensure the preservation of these ecological activities and the sustainability of life supporting systems.
B: To conserve species diversity and range of genetic material
- Plant conservation aims to protect the diverse range of plant species that exist on our planet.
- Each plant species has its unique genetic material, which is essential for the adaptation and evolution of plants.
- Conserving plant species diversity ensures the preservation of valuable genetic resources that can be utilized for various purposes, such as crop improvement, medicine, and ecological restoration.
- It also helps to safeguard against the loss of plant species due to habitat destruction, climate change, and other threats.
C: Both the above
- The main aim of plant conservation is a combination of conserving the necessary ecological activities and life supporting systems, as well as preserving species diversity and range of genetic material.
- These two aims are interconnected and mutually dependent on each other.
- By achieving both aims, we can ensure the long-term sustainability of ecosystems, protect biodiversity, and maintain the overall health of the planet.
D: None of the above
- This option is not the correct answer as both A and B accurately reflect the main aims of plant conservation.