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Which organelle contains enzymes for cellular respiration?

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Cellular respiration is a complex process by which cells convert nutrients, primarily glucose, into energy in the form of adenosine triphosphate (ATP). This process occurs in both the cytoplasm and mitochondria of cells and involves three main stages: glycolysis, the Krebs cycle (citric acid cycle), and the electron transport chain (ETC).  Note : Cellular respiration is typically described as a three-stage process, although some explanations break it down into four stages for clarity. Four stages: glycolysis, Pyruvate Oxidation, the Krebs cycle (citric acid cycle), and the electron transport chain (ETC).  01. Glycolysis Location: Cytoplasm Process:  Glycolysis is the first step in cellular respiration and occurs in the cytoplasm. It involves the breakdown of one molecule of glucose (a six-carbon sugar) into two molecules of pyruvate (each containing three carbons). This process consists of ten enzymatic steps that convert glucose into pyruvate, producing a net gain of energy-rich mol
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Why the mitochondria is called the "powerhouse" of the cell?

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Mitochondria are double membrane-bound organelles found in the cytoplasm of nearly all eukaryotic cells. They are often described as the "powerhouses" of the cell due to their primary role in generating adenosine triphosphate (ATP), the main energy currency of the cell. Mitochondria (singular = mitochondrion) were first discovered by Albert vonkollicker in 1850 from striated muscle tissue of insects and the term "mitochondrion" (In Greek, Mito = "thread" + chondrion = "granule") was coined by Carl Benda because of the thread like appearance of these granules when examined under light microscope. Structure of Mitochondria Mitochondria occupy up to 25% volume of the cytoplasm. A mitochondrion is enclosed by a double membrane. Outer Membrane: Permeable barrier with porins for metabolite exchange. Outer membrane is constituted by 50% lipids and 50% proteins along with porin protein (conferring permeability to molecules with molecular weight as hig
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Vitamin A

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Vitamin A is a fat-soluble vitamin essential for many physiological functions in the body.  Chemical name - Retinol Retinol or All-Trans-Retinol and Beta-carotene Retinol and beta-carotene are both related to vitamin A but differ in several significant ways: Retinol: Retinol is a form of preformed vitamin A. It is found in animal-based foods such as liver, fish oils, milk, eggs, and some fortified foods. Retinol is directly usable by the body. It plays a crucial role in vision, immune function, and skin health. It does not require conversion to be utilized by the body. Retinol is more potent than beta-carotene, meaning it is more effective in smaller amounts. Molecular formula - C₂₀H₃₀O Molecular weight - 286.46 g/mol Beta-Carotene: Beta-carotene is a provitamin A carotenoid. It is found in plant-based foods such as carrots, sweet potatoes, spinach, and other leafy green vegetables. Beta-carotene is an antioxidant and a precursor to vitamin A. The body converts beta-carotene into reti
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Regulating Act 1773

Regulating Act, 1773 passed by the British parliament to control the affairs of East India company in India. For the first time it recognised the political and administrative functions of the company and laid the foundation of the central administration in India. This Act was passed by the Parliament of Great Britain and aimed to regulate the affairs of the British East India Company, which had established a strong presence in India. The Act was the first attempt by the British government to establish centralized control over the Company’s operations and its relations with Indian territories. The act elevated Governor of Bengal Warren Hastings to Governor-General of Bengal and submitted the presidencies of Madras and Bombay under the Bengal’s control. The Act established a Governor’s Council in each presidency (Bengal, Madras, and Bombay), comprising the Governor and four councillors. These councillors were commonly known as Council of Four. Supreme court was established in 1774 at
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Explain the fluid mosaic model of the plasma membrane

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The fluid mosaic model of plasma membrane was proposed by the S.J. Singer and Garth L. Nicolson in 1972. The fluid mosaic model of plasma membrane describes the structure of the plasma membrane. Plasma membrane (also called cell membrane or plasmalemma) is a thin, elastic, semifluid, living protective membrane which separate the internal contents (cytoplasm and cytoplasmic organelles) from the external surroundings. The plasma membrane control the passage of materials, such as organic molecules, ions and water between the cells and its surrounding. It also prevents the passage of some substances to cell exterior to maintain the ionic concentration gradient between the cytoplasm and the surroundings.   The plasma membrane is made up of proteins and lipids. Several models were proposed to explain the arrangement of proteins and lipids is the membrane; however, the fluid-mosaic model proposed by the S.J. Singer and Garth L. Nicolson in 1972 is the most widely accepted model.  Accordi
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Which organelles are involved in photosynthesis?

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The primary organelles involved in photosynthesis are the chloroplasts. Chloroplasts Except for vacuoles, chloroplast, the double-mebraned organelle, are the largest and the most characteristic organelles in plant cell. These are specialized organelles found in the cells of plants and algae. Chloroplasts contain the pigment chlorophyll, which captures light energy for photosynthesis. Like mitochondria, chloroplasts have their own genome and contain 70s ribosomes, DNA and enzymes involve in protein synthesis. The chloroplast belongs to a group of related organelles in plants called plastids. Plastids differ in structure, carry out diverse functions, and are classified according to the kinds of pigments they contain.  Chloroplasts contain chlorophyll while chromoplasts are lycopene-containing plastids and are responsible for yellow, orange and red colors of some flowers and fruits. Leucoplasts are non-pigmented plastids, and amyloplasts are starch-storing plastids of potato tubers. All
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Introduction to Cell Biology

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Cell biology, also known as cellular biology or cytology, is the branch of biology that studies cells—the fundamental units of life. This field explores the structure, function, and behavior of cells, encompassing a wide range of topics that are essential for understanding life at its most basic level. Cell biology encompasses both prokaryotic and eukaryotic cells and has many subtopics which may include the study of cell metabolism, cell communication, cell cycle, biochemistry, and cell composition. The study of cells is performed using several microscopy techniques, cell culture, and cell fractionation. These have allowed for and are currently being used for discoveries and research pertaining to how cells function, ultimately giving insight into understanding larger organisms. Historical Perspective The study of cells dates back to the 17th century when the invention of the microscope enabled scientists to observe structures that were previously invisible to the naked eye. In 1665,
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Introduction to Cell Biology - MCQ Practice Set

01. What significant cellular component did Robert Brown discover in 1831? A) Mitochondria B) Nucleus C) Endoplasmic reticulum D) Golgi apparatus Answer: B) Nucleus Explanation: Robert Brown discovered the nucleus in 1831, identifying it as a key organelle within cells. The nucleus houses genetic material (DNA) and regulates various cellular activities, including gene expression, DNA replication, and interaction with other organelles. This discovery was crucial for understanding cell structure and function. 02. Who first coined the term "cell" while examining cork tissue under a microscope? A) Anton Van Leeuwenhoek B) Robert Hooke C) Matthias Schleiden D) Theodor Schwann Answer: B) Robert Hooke Explanation: Robert Hooke coined the term "cell" in 1665 when he observed cork tissue under a simple microscope. He noticed small, box-like compartments that reminded him of the cells in a monastery, leading to the use of the term "cell" in biological contexts. His
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International Day for the Eradication of Poverty

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International Day for the Eradication of Poverty is celebrated every year on 17 October. The day is dedicated to create awareness and promote global measures for the prevention of poverty. One of the major challenges in the world that needs to be addressed for the betterment of society is Poverty. The International Poverty Eradication Day is an opportunity to highlight the problems faced by underprivileged people in their day-to-day lives, and provide necessary support to them. Poor people struggle to live a normal life and are deprived from basic human rights like education, health, and employment. Eradicating poverty is a chance for the world to promote equality, and allow people from all sectors to live with honour and dignity. International Day for the Eradication of Poverty serves as a platform to foster economic stability on a global level and encourage social inclusion. The International Day for the Eradication of Poverty traces its origins back to October 17, 1987, when over a
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World Osteoporosis Day

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World Osteoporosis Day, observed on 20 October annually, is a global awareness campaign aimed at highlighting the importance of bone health and raising awareness about osteoporosis, a common but often overlooked condition that weakens bones, making them fragile and more susceptible to fractures.  Note - "Osteoporosis is a medical condition characterized by weakened bones, making them fragile and susceptible to fractures or breaks. It occurs when the body loses too much bone mass or doesn't produce enough new bone, leading to a reduction in bone density. This disease often progresses silently, with no symptoms until a fracture occurs. Common areas for fractures include the hips, spine, and wrists. Factors like aging, hormonal changes, inadequate calcium and vitamin D intake, a sedentary lifestyle, and certain medications can increase the risk of developing osteoporosis. Prevention involves a balanced diet, regular exercise, and bone density screenings." This day serves as
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