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Structure of m RNA

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  Structure of mRNA (Messenger RNA) mRNA is a single-stranded RNA molecule that carries genetic information from DNA to ribosomes for protein synthesis. 1. General Features Composed of ribonucleotides (A, U, G, C) Single-stranded and linear Has 5′ → 3′ polarity Sequence is complementary to the DNA template strand 2. Structural Components of Eukaryotic mRNA 1. 5′ Cap Modified 7-methyl guanosine (m⁷G) added to the 5′ end Functions: Protects mRNA from degradation Helps ribosome binding Required for nuclear export 2. 5′ Untranslated Region (5′ UTR) Lies between the 5′ cap and start codon Regulates translation initiation 3. Coding Region Begins with start codon (AUG) Ends with a stop codon (UAA, UAG, or UGA) Contains codons that specify amino acids 4. 3′ Untranslated Region (3′ UTR) Located after the stop codon Involved in: mRNA stability Regulation of translation 5. Poly-A Tail A stretch of adenine nucleotides (≈50–250 A’s) at the 3′ end Functions: Prevents degradation Enhances t...
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Explain the role of decomposers in nutrients cycling in an ecosystem

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      Decomposers play an indispensable role in nutrient cycling within an ecosystem by breaking down dead organic matter and returning essential elements to the environment. This process is crucial for sustaining life and maintaining ecosystem health. Here's a breakdown of their role: Definition of Decomposers  Decomposers are organisms, primarily bacteria and fungi, along with certain invertebrates such as earthworms and insects, that obtain nutrients and energy by breaking down dead organisms and animal wastes. They are also referred to as saprophytic organisms or detritivores. Process of Decomposition  Decomposers facilitate the process of decomposition, which involves the breakdown of complex organic compounds into simpler inorganic substances. They use specialized enzymes to transform complex materials like carbohydrates, proteins, and fats into smaller, usable nutrients. Fungi, for instance, are particularly effective at breaking down tough materials like...
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ECOLOGICAL SUCCESSION

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  Ecological succession is the process by which the species composition of an ecosystem changes over time. It involves a predictable sequence of community replacements, leading to a stable, mature ecosystem known as the climax community. Two primary types of ecological succession are   primary succession   and   secondary succession , with additional classifications like autogenic, allogenic, progressive, and retrogressive succession. Primary Succession Primary succession occurs in lifeless areas devoid of soil. These areas include newly formed volcanic rock, sand dunes, or exposed glacial deposits. The process begins with  pioneer species  such as lichens and mosses, which can survive in harsh conditions and start to break down the substrate. Over time, these organisms contribute to soil formation through decomposition. As the soil develops, it supports more complex plants like grasses, shrubs, and eventually trees. This process can take hundreds to thousa...
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Diabetes

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  Diabetes mellitus, commonly known as diabetes, is a group of chronic endocrine diseases characterized by persistently high blood sugar (glucose) levels. This occurs either because the pancreas does not produce enough insulin, or because the body's cells become unresponsive to the insulin that is produced. Insulin is a hormone vital for helping glucose enter cells to be used for energy. Without sufficient insulin action, glucose accumulates in the bloodstream, leading to various health complications over time. Types of Diabetes The main types of diabetes include: Type 1 Diabetes  An autoimmune condition where the body's immune system mistakenly attacks and destroys the insulin-producing beta cells in the pancreas, leading to little or no insulin production. It is often diagnosed in childhood but can occur at any age. Type 2 Diabetes  The most common type, occurring when the body becomes resistant to insulin's effects or the pancreas doesn't produce enough insulin to ma...
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