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Structure and function of biological molecules and their metabolic pathways.
Biochemistry is the study of the chemical processes that occur within living organisms, including the structure and function of biological molecules and their metabolic pathways.
Biological molecules, such as carbohydrates, proteins, and nucleic acids, are composed of atoms bonded together by covalent chemical bonds. Carbohydrates consist of carbon, hydrogen, and oxygen atoms, while proteins contain carbon, hydrogen, oxygen, nitrogen, and sulfur atoms. Nucleic acids, including DNA and RNA, are made up of carbon, hydrogen, oxygen, nitrogen, and phosphorus atoms. The unique arrangement of these atoms determines the function and properties of each biological molecule.
Metabolic pathways are series of chemical reactions that occur within cells to convert one molecule into another. These pathways involve enzymes, which are biological molecules that speed up chemical reactions without being consumed by the reaction. Glycolysis is a metabolic pathway that breaks down glucose into pyruvate, while the citric acid cycle and electron transport chain generate energy from pyruvate.
Enzymes are biological molecules that catalyze chemical reactions by lowering the activation energy required for the reaction to occur. Enzyme activity is regulated through various mechanisms, including substrate concentration, temperature, pH, and allosteric effectors. Feedback inhibition, where the end product of a metabolic pathway inhibits an earlier step in the pathway, is another mechanism of enzyme regulation.
Cells produce energy through cellular respiration, which involves glycolysis, the citric acid cycle, and oxidative phosphorylation. Energy is stored in the form of ATP, NADH, and FADH2 molecules. The electron transport chain generates a proton gradient across the mitochondrial membrane, driving ATP synthesis.
DNA contains genetic information encoded in its sequence of nucleotides. Transcription involves the synthesis of RNA from DNA, while translation is the process by which amino acids are assembled into proteins based on mRNA sequences. Gene regulation occurs through transcription factors, enhancers, and promoters.
Chemical reactions in biochemistry often involve equilibrium states, where the rates of forward and reverse reactions are equal. Le Chatelier's principle states that a change in concentration or temperature will shift the equilibrium position. Biochemical reactions can be classified as reversible or irreversible.
Biochemistry has numerous applications in medicine, agriculture, and industry. For example, enzymes are used in laundry detergents to break down protein-based stains, while insulin is a hormone produced through biochemically engineered bacteria. Gene therapy involves the use of biochemistry to treat genetic disorders.
Various biochemical techniques and methods are used to analyze biological molecules and reactions. These include chromatography, electrophoresis, spectroscopy, and enzyme assays. PCR (polymerase chain reaction) is a technique used to amplify specific DNA sequences.
What is the primary function of enzymes in biochemical reactions?
Which of the following is NOT a type of biomolecule?
What is the process by which cells generate energy from glucose called?
Which of the following is a type of metabolic pathway?
What is the process by which plants convert light energy into chemical energy called?
What contains genetic information and is responsible for passing traits from one generation to the next?
Which of the following is a type of biochemical reaction?
What is the process by which cells convert energy from food into a form that can be used to power cellular activities called?
What is the primary function of nucleic acids in biochemical reactions?
What is the process by which cells generate energy through glycolysis, the citric acid cycle, and oxidative phosphorylation called?
Discuss the importance of biochemistry in understanding cellular processes. (20 marks)
Explain how biochemistry has practical applications in everyday life. (20 marks)