What Is DNA Fingerprinting? Mention Its Applications DNA fingerprinting , also known as DNA profiling , is a technique used to identify an individual by analysing specific regions of their DNA that show variation among individuals. What Is DNA Fingerprinting? DNA fingerprinting is based on DNA polymorphism , particularly variation in repetitive DNA sequences. In the classical technique described in NCERT, Variable Number Tandem Repeats (VNTRs) are important markers. VNTRs are repetitive DNA sequences in which the number of repeat units varies among individuals. Analysis of these variable regions produces a DNA profile that can be compared between biological samples. Principle of DNA Fingerprinting The basic principle is that certain repetitive regions of DNA differ considerably among individuals. By analysing these variable regions, a characteristic DNA pattern can be obtained. Therefore: DNA polymorphism → Variable repetitive DNA sequences → D...

Which Aspect Forms the Basis of DNA Fingerprinting? Question: Which aspect forms the basis of DNA fingerprinting? Answer The basis of DNA fingerprinting is the variation in repetitive DNA sequences, particularly Variable Number Tandem Repeats (VNTRs). DNA fingerprinting, also called DNA profiling , is based on the fact that certain regions of DNA show considerable variation among individuals. These variable repetitive sequences can be used to distinguish one individual from another. What Are VNTRs? VNTRs (Variable Number Tandem Repeats) are repetitive DNA sequences in which the number of repeated units varies among individuals. Because the number and arrangement of these repetitive sequences differ between individuals, they produce different DNA profiles. Why Is DNA Fingerprinting Individual-Specific? Most of the DNA sequence is similar among humans, but certain repetitive regions are highly variable. The differences in these regions cr...

Which of the Following Constitutes a Food Chain? Question: Which of the following constitutes a food chain? Answer Grass → Grasshopper → Frog → Snake → Hawk This sequence constitutes a food chain because each organism is eaten by the organism that follows it. It represents the transfer of food and energy through successive trophic levels. Explanation Grass – Producer (1st trophic level) Grasshopper – Primary consumer (2nd trophic level) Frog – Secondary consumer (3rd trophic level) Snake – Tertiary consumer (4th trophic level) Hawk – Higher-level consumer What Is a Food Chain? A food chain is a sequence of organisms in which each organism serves as food for the next organism. It shows the movement of food and the transfer of energy from one trophic level to another. A simple grazing food chain can be represented as: Producer → Herbivore → Carnivore → Higher-level consumer More Examples of Food C...

Which of the Following Constitutes a Food Chain? A food chain is a sequence of organisms through which food, energy, and nutrients pass as one organism eats another. A correct food chain generally begins with a producer and proceeds through different levels of consumers. Which of the Following Constitutes a Food Chain? Example of a correct food chain: Grass → Grasshopper → Frog → Snake → Hawk This sequence constitutes a food chain because each organism serves as a source of food for the organism at the next trophic level. Understanding the Food Chain In the above example: Grass – Producer Grasshopper – Primary consumer Frog – Secondary consumer Snake – Higher-level consumer Hawk – Top consumer Energy therefore moves from the producer to successive consumers. What Is a Food Chain? According to ecological principles, organisms in an ecosystem are linked through feeding relationships. The transfer of food and energy from one organism to another form...

What Is Ozone and How Does It Affect an Ecosystem? Ozone (O 3 ) is a molecule made up of three oxygen atoms. It is an important component of the atmosphere and plays different roles depending on where it is present. Ozone in the stratosphere protects life from harmful ultraviolet (UV) radiation, while ozone near the Earth's surface can act as an air pollutant and harm living organisms. 📚 NEET Biology Study Hub Looking for more NCERT-focused Biology notes, diagrams, MCQs and NEET preparation resources? Explore NEET Biology →    What Is Ozone? Ozone is a highly reactive form of oxygen. Unlike the oxygen we normally breathe, which contains two oxygen atoms (O 2 ), ozone contains three oxygen atoms (O 3 ). Most atmospheric ozone is found in the stratosphere , where it forms the ozone layer. This layer absorbs a large portion of the Sun's harmful ultraviolet radiation. How Does Ozone Protect an Ecosystem? The ozone layer acts as ...

What Is the Role of Decomposers in an Ecosystem? Decomposers play a vital role in an ecosystem by breaking down dead plants, animals, and organic matter into simpler substances. They help recycle nutrients and make them available again to plants. 📚 NEET Biology Study Hub Looking for more NCERT-focused Biology notes, diagrams, MCQs and NEET preparation resources? Explore NEET Biology →    What Are Decomposers? Decomposers are organisms that obtain their nutrition by breaking down dead and decaying organic matter. The major decomposers in an ecosystem are bacteria and fungi . They secrete digestive enzymes onto the dead organic matter and break complex organic substances into simpler substances. Role of Decomposers in an Ecosystem 1. Decomposition of Dead Organic Matter Decomposers break down the dead remains of plants and animals and other organic wastes. This prevents the continuous accumulation of dead organic matter in t...

What Is the Role of Decomposers in the Ecosystem? Decomposers are organisms that break down dead plants, animals, and organic wastes into simpler substances. They play a vital role in maintaining the balance of an ecosystem by recycling nutrients back into the environment. 📚 NEET Biology Study Hub Looking for more NCERT-focused Biology notes, diagrams, MCQs and NEET preparation resources? Explore NEET Biology →    What Are Decomposers? Decomposers are mainly bacteria and fungi . They obtain their nutrition from dead and decaying organic matter and convert complex organic substances into simpler inorganic substances. Examples include: Bacteria Fungi Major Roles of Decomposers in an Ecosystem 1. Decomposition of Dead Organisms Decomposers break down the remains of dead plants and animals into simpler substances. This process prevents the accumulation of dead organic matter in the ecosystem. 2. Recycling ...