Most living organisms cannot survive at temperature above 45°C°. How are some microbes able to live in habitats with temperatures exceeding 100°C?
Solution and Explanation
Top Questions on Organisms and Populations
- Write the number of RNA polymerases involved in the transcription of DNA in a prokaryote and eukaryotes.
- CBSE CLASS XII - 2024
- Biology
- Organisms and Populations
- Write the specific sequence of DNA segment recognised by the restriction endonuclease EcoRI.
- CBSE CLASS XII - 2024
- Biology
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- List the attributes that populations but not individuals possess.
- CBSE CLASS XII
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- Which of the following is not true for a species ?
- Biology
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- Which one of the following pairs is mismatched ?
- Biology
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Questions Asked in CBSE CLASS XII exam
A school is organizing a debate competition with participants as speakers and judges. $ S = \{S_1, S_2, S_3, S_4\} $ where $ S = \{S_1, S_2, S_3, S_4\} $ represents the set of speakers. The judges are represented by the set: $ J = \{J_1, J_2, J_3\} $ where $ J = \{J_1, J_2, J_3\} $ represents the set of judges. Each speaker can be assigned only one judge. Let $ R $ be a relation from set $ S $ to $ J $ defined as: $ R = \{(x, y) : \text{speaker } x \text{ is judged by judge } y, x \in S, y \in J\} $.
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- Relations and Functions
Given below is a heterogeneous RNA formed during Eukaryotic transcription:
How many introns and exons respectively are present in the hnRNA?
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- Eukaryotic Transcription
- Four friends Abhay, Bina, Chhaya, and Devesh were asked to simplify \( 4 AB + 3(AB + BA) - 4 BA \), where \( A \) and \( B \) are both matrices of order \( 2 \times 2 \). It is known that \( A \neq B \) and \( A^{-1} \neq B \). Their answers are given as:
A certain reaction is 50 complete in 20 minutes at 300 K and the same reaction is 50 complete in 5 minutes at 350 K. Calculate the activation energy if it is a first order reaction. Given: \[ R = 8.314 \, \text{J K}^{-1} \, \text{mol}^{-1}, \quad \log 4 = 0.602 \]
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- Organic Reactions
- Using integration, find the area of the region bounded by the line \[ y = 5x + 2, \] the \( x \)-axis, and the ordinates \( x = -2 \) and \( x = 2 \).
- CBSE CLASS XII - 2025
- Evaluation of Definite Integrals by Substitution
Concepts Used:
Organisms and their Environments
Ecology is the branch of biology that involves the study of the interactions that takes place between an organism and its environment. Any biological organization consists of 4 levels, namely, Organisms, Populations, Biomes, and Communities.
Organisms:
An Organism is an attached living system that lives in an environment. They are able to retain specific behaviours and structure such as bacteria, fungi, plants, animals, and humans. A population is formed by the collection of all these organisms. The collection of population forms a community that helps in the operation of ecosystems.
Environment:
The study of the interaction of organisms in an area with the surrounding environment is Ecology. This interaction constitutes an overall adaptation of the organisms to their environment that also includes the continuity of species.
The environment comprises of both biotic (living things) and abiotic components (non-living things)
Food Chain:
Food Chain is the transfer of food energy from the plant source through a series of organisms that consume and are consumed.
Grass(Producer) → Deer(Herbivore) → Tiger(Carnivore), Grass(Producers) → Insect(Herbivores) → Frog(Carnivores) → Snake(Secondary Carnivore).
Food Web:
Food web is the interlocking pattern of multiple food chains in the ecosystem. In this, many food chains are interconnected and there are increased possibilities of eating and getting eaten by different organisms of various species.