Erratum to: A Systematic Review a Day, Keeps the Reader Away!
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Overview
Synthesis of new DNA molecules starts when DNA polymerase links nucleotides together in a sequence that is complementary to the template DNA strand. DNA polymerase has a higher affinity for the correct base to ensure fidelity in DNA replication. The DNA polymerase furthermore proofreads during replication, using an exonuclease domain that cuts off incorrect nucleotides from the nascent DNA strand.
Errors during Replication Are Corrected by the DNA Polymerase Enzyme
Genomic DNA is...
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Biochemical reactions are occurring constantly in cells, converting starting substances to different products, usually with the help of enzymes that speed the reactions. Without enzymes, it would take far too long for most reactions to occur to be useful to the cell!
Since enzymes help control the rate of reactions, their activity is regulated so that appropriate amounts of starting materials, intermediate metabolites, and products are maintained in the cell. Excessive build-up or depletion of...
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In most cases, excessive hormone production is prevented by negative feedback—a loop that starts with a stimulus inducing the release of a particular substance, like a hormone, to maintain a certain level before triggering a signal that results in a decrease in further release of the hormone.
Blood-sugar Levels
For example, an increase in blood glucose levels releases the hormone insulin from beta cells of the pancreas into the bloodstream, delivering insulin to cells throughout the...
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The scientific method is a detailed, empirical problem-solving process used by biologists and other scientists. This iterative approach involves formulating a question based on observation, developing a testable potential explanation for the observation (called a hypothesis), making and testing predictions based on the hypothesis, and using the findings to create new hypotheses and predictions.
Generally, predictions are tested using carefully-designed experiments. Based on the outcome of these...
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The Problem-Oriented Medical Record (POMR) revolutionized medical record-keeping by introducing a systematic approach focusing on the patient's problems rather than merely listing symptoms. Dr. Lawrence Weed's introduction of this method in the 1960s marked a significant advancement in medical documentation. The POMR framework consists of four key components: the database, problem list, plan of care, and progress notes.
Database: This section documents crucial medical information...
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Animals have evolved different strategies for excretion, the removal of waste from the body. Most waste must be dissolved in water to be excreted, so an animal’s excretory strategy directly affects its water balance.
Nitrogenous wastes are some of the most significant forms of animal waste. Nitrogen is released when proteins and nucleic acids are broken down for energy or conversion into carbohydrates and fats. Proteins are broken down into amino acids and nucleic acids into nitrogenous...