Download Road Map Biochemistry by Richard G. Macdonald and William G. Chaney
You'll never find an easier, more efficient, and more focused way to ace biochemistry and biochemistry-related questions on the USMLE and course examinations than the USMLE Road Map. Designed to provide maximum learning in minimum time, this fully updated USMLE Road Map offers a concise, creative, and well-illustrated approach to mastering biochemistry.
Free Download Essential Forensic Biology by Alan Gunn
This book is an introduction to the application of biology in legal investigations. Fully revised and updated throughout, the second edition of this highly successful textbook offers an accessible overview to the essentials of the subject providing a balanced coverage of the range of organisms used as evidence in forensic investigations; invertebrates, vertebrates, plants and microbes. The book provides an overview of the decay process and discusses the role of forensic indicators – human fluids and tissues, including blood cells, bloodstain pattern analysis, hair, teeth, bones, and wounds. It also examines the study of forensic biology in cases of suspicious death. The coverage of molecular techniques has been expanded throughout with additional material on bioterrorism and wildlife forensics now included. The use of DNA and RNA for the identification of individuals and their personal characteristics is now covered along with a discussion of the ethical issues associated with the maintenance of DNA databases.
• Fully revised and updated new edition of this highly successful textbook.
• Includes self–assessment questions at the end of each chapter and case studies.
• Now in full colour throughout.
• Includes a supplementary website ( www.wileyeurope.com/college/gunn ) covering additional material and self–test questions to reinforce student understanding.
Drawing on the highly successful first edition, this newly-revised second edition covers the many advances made in PCR technology since the first book, which has been used in more than 10,000 laboratories worldwide. As PCR technology has advanced significantly since the first edition, and has expanded its use in the clinical laboratory of physician/researchers, the scope of this book is greatly expanded to enable researchers at all levels to easily reproduce and adapt PCR experiments to their own specific requirements. The meethods selected represent worked examples from many fields that can be reproduced and adapted for use within the reader's laboratory. The authors have provided both a primer to allow the reader to gain basic experience of different PCR techniques, as well as in-depth insight into a variety of the more complex applications of PCR. This book will be essential for the labs of all biochemists, molecular biologists, geneticists and researchers utilizing the PCR techinque in their work .
Thoroughly updated for its Fifth Edition, Lippincott’s Illustrated Reviews: Biochemistry enables students to quickly review and assimilate large amounts of complex information through powerful visual resources essential to mastery of difficult biochemical concepts. Its signature outline format, full-color illustrations, end-of-chapter summaries, and USMLE-style review questions make it one of the most user-friendly books in the field. New features include expanded coverage of molecular biology.
A companion website offers fully searchable online text and additional USMLE-style questions for students and an image bank for faculty.
Need to master the concepts of biochemistry? Grab the Inkling version of Lippincott’s Illustrated Reviews: Biochemistry. Spin a molecular compound on its axis with just your fingertips, or share notes with a friend. The Inkling version also includes an additional review chapter with 450 USMLE-style questions—study buddy not included.
Table of Contents
chapter 1: Amino Acids
chapter 2: Structure of Proteins
chapter 3: Globular Proteins
chapter 4: Fibrous Proteins
chapter 5: Enzymes
chapter 6: Bioenergetics and Oxidative Phosphorylation
chapter 7: Introduction to Carbohydrates
chapter 8: Glycolysis
chapter 9: Tricarboxylic Acid Cycle
chapter 10: Gluconeogenesis
chapter 11: Glycogen Metabolism
chapter 12: Metabolism of Monosaccharides and Disaccharides
chapter 13: Pentose Phosphate Pathway and NADPH
chapter 14: Glycosaminoglycans, Proteoglycans, and Glycoproteins
chapter 15: Metabolism of Dietary Lipids
chapter 16: Fatty Acid and Triacylglycerol Metabolism
chapter 17: Complex Lipid Metabolism
chapter 18: Cholesterol and Steroid Metabolism
chapter 19: Amino Acids: Disposal of Nitrogen
chapter 20: Amino Acid Degradation and Synthesis
chapter 21: Conversion of Amino Acids to Specialized Products
chapter 22: Nucleotide Metabolism
chapter 23: Metabolic Effects of Insulin and Glucagon
chapter 24: The Feed/Fast Cycle
chapter 25: Diabetes Mellitus
chapter 26: Obesity
chapter 27: Nutrition
chapter 28: Vitamins
chapter 29: DNA Structure, Replication and Repair
chapter 30: RNA Structure, Synthesis and Processing
chapter 31: Protein Synthesis
chapter 32: Regulation of Gene Expression
chapter 33: Biotechnology and Human Disease
Lippincott’s Illustrated Reviews: Biochemistry 5th edition by Richard A. Harvey
Biochemistry plays an important role in all areas of the biological and medical sciences. With most of the research or diagnosis involved in these areas being based on biochemically obtained observations, it is essential to have a profile of well standardized protocols. This manual is a basic guide for all students, researchers and experts in biochemistry, designed to help readers in directly starting off their experiments without prior knowledge of the protocol. The book dwells on the concepts used in designing the methodologies, thereby giving ample room for researchers to modify them according to their research requirements.
Contents:
Protein Purification
Protein Analysis
Lipid Analysis
Mammalian Cell Culture
Microscopy
Assays
Autoradiography
Microbial physiology, biochemistry, and genetics allowed the formulation of concepts that turned out to be important in the study of higher organisms. In the first section, the principles of bacterial growth are given, as well as the description of the different layers that enclose the bacterial cytoplasm, and their role in obtaining nutrients from the outside media through different permeability mechanism described in detail. A chapter is devoted to allostery and is indispensable for the comprehension of many regulatory mechanisms described throughout the book. Another section analyses the mechanisms by which cells obtain the energy necessary for their growth, glycolysis, the pentose phosphate pathway, the tricarboxylic and the anaplerotic cycles. Two chapters are devoted to classes of microorganisms rarely dealt with in textbooks, namely the Archaea, mainly the methanogenic bacteria, and the methylotrophs. Eight chapters describe the principles of the regulations at the transcriptional level, with the necessary knowledge of the machineries of transcription and translation. The next fifteen chapters deal with the biosynthesis of the cell building blocks, amino acids, purine and pyrimidine nucleotides and deoxynucleotides, water-soluble vitamins and coenzymes, isoprene and tetrapyrrole derivatives and vitamin B12. The two last chapters are devoted to the study of protein-DNA interactions and to the evolution of biosynthetic pathways. The considerable advances made in the last thirty years in the field by the introduction of gene cloning and sequencing and by the exponential development of physical methods such as X-ray crystallography or nuclear magnetic resonance have helped presenting metabolism under a multidisciplinary attractive angle. The level of readership presupposes some knowledge of chemistry and genetics at the undergraduate level. The target group is graduate students, researchers in academia and industry.
Biochemistry: The Molecular Basis of Life is the ideal text for students who do not specialize in biochemistry but who require a strong grasp of biochemical principles. The goal of this edition has been to enrich the coverage of chemistry while better highlighting the biological context. Once concepts and problem-solving skills have been mastered, students are prepared to tackle the complexities of science, modern life, and their chosen professions.
DISTINCTIVE FEATURES
A Review of Basic Principles. To ensure that all students are sufficiently prepared for acquiring a meaningful understanding of biochemistry, the first four chapters–now streamlined for easier coverage and self-study assessment–review the principles of relevant topics such as organic functional groups, noncovalent bonding, thermodynamics, and cell structure.
Chemical and Biological Principles in Balance. Comprehensive coverage offers each instructor the flexibility to decide how much chemistry or biology he/she would like to present. Chemical mechanisms are always presented within the physiological context of the organism.
Real-World Relevance. Because students who take the survey of biochemistry course come from a range of backgrounds and have diverse career goals, the updated fifth edition consistently demonstrates the fascinating connections between biochemical principles and the fields of medicine, nutrition, agriculture, bioengineering, and forensics.
The Most Robust Problem-Solving Program Available.
* In-chapter “Worked Problems” illustrate how quantitative problems are solved and provide students with opportunities to put their knowledge into action right when new concepts are introduced.
* Dozens of “Questions” are interspersed throughout the chapters, getting students critically thinking about high-interest topics.
* Finally, hundreds of multiple-choice and short-answer questions at the end of the chapters test students’ knowledge, develop their conceptual understanding, and encourage them to apply what they have learned.
Simple, Clear Illustrations. Biochemical concepts often require a high degree of visualization, and the McKee and McKee art program brings complex processes to life. The book includes 700+ full-color figures, many newly enhanced for a more vivid presentation in three dimensions and consistent scale and color for chemical structures.
Click here to Download (DepositeFiles Link) Note: Use Regular Download in Depositefiles
Books Description
Cyanobacteria, also known as blue-green algae, blue-green bacteria or cyanophyta, is a phylum of bacteria that obtain their energy through photosynthesis. They are a significant component of the marine nitrogen cycle and an important primary producer in many areas of the ocean, but are also found in habitats other than the marine environment; in particular, cyanobacteria are known to occur in both freshwater and hypersaline inland lakes. They are found in almost every conceivable environment, from oceans to fresh water to bare rock to soil.
Cyanobacteria are the only group of organisms that are able to reduce nitrogen and carbon in aerobic conditions, a fact that may be responsible for their evolutionary and ecological success. Certain cyanobacteria also produce cyanotoxins. This new book presents a broad variety of international research on this important organism.
Handbook on Cyanobacteria: Biochemistry, Biotechnology and Applications
Click here to Download (DepositeFiles Link) Note: Use Regular Download in Depositefiles
Books Description
Cyanobacteria, also known as blue-green algae, blue-green bacteria or cyanophyta, is a phylum of bacteria that obtain their energy through photosynthesis. They are a significant component of the marine nitrogen cycle and an important primary producer in many areas of the ocean, but are also found in habitats other than the marine environment; in particular, cyanobacteria are known to occur in both freshwater and hypersaline inland lakes. They are found in almost every conceivable environment, from oceans to fresh water to bare rock to soil.
Cyanobacteria are the only group of organisms that are able to reduce nitrogen and carbon in aerobic conditions, a fact that may be responsible for their evolutionary and ecological success. Certain cyanobacteria also produce cyanotoxins. This new book presents a broad variety of international research on this important organism.
Handbook on Cyanobacteria: Biochemistry, Biotechnology and Applications
Thoroughly updated for its Fifth Edition, Lippincott’s Illustrated Reviews: Biochemistry enables students to quickly review and assimilate large amounts of complex information through powerful visual resources essential to mastery of difficult biochemical concepts. Its signature outline format, full-color illustrations, end-of-chapter summaries, and USMLE-style review questions make it one of the most user-friendly books in the field. New features include expanded coverage of molecular biology.
A companion website offers fully searchable online text and additional USMLE-style questions for students and an image bank for faculty.
Need to master the concepts of biochemistry? Grab the Inkling version of Lippincott’s Illustrated Reviews: Biochemistry. Spin a molecular compound on its axis with just your fingertips, or share notes with a friend. The Inkling version also includes an additional review chapter with 450 USMLE-style questions—study buddy not included.
Table of Contents
chapter 1: Amino Acids
chapter 2: Structure of Proteins
chapter 3: Globular Proteins
chapter 4: Fibrous Proteins
chapter 5: Enzymes
chapter 6: Bioenergetics and Oxidative Phosphorylation
chapter 7: Introduction to Carbohydrates
chapter 8: Glycolysis
chapter 9: Tricarboxylic Acid Cycle
chapter 10: Gluconeogenesis
chapter 11: Glycogen Metabolism
chapter 12: Metabolism of Monosaccharides and Disaccharides
chapter 13: Pentose Phosphate Pathway and NADPH
chapter 14: Glycosaminoglycans, Proteoglycans, and Glycoproteins
chapter 15: Metabolism of Dietary Lipids
chapter 16: Fatty Acid and Triacylglycerol Metabolism
chapter 17: Complex Lipid Metabolism
chapter 18: Cholesterol and Steroid Metabolism
chapter 19: Amino Acids: Disposal of Nitrogen
chapter 20: Amino Acid Degradation and Synthesis
chapter 21: Conversion of Amino Acids to Specialized Products
chapter 22: Nucleotide Metabolism
chapter 23: Metabolic Effects of Insulin and Glucagon
chapter 24: The Feed/Fast Cycle
chapter 25: Diabetes Mellitus
chapter 26: Obesity
chapter 27: Nutrition
chapter 28: Vitamins
chapter 29: DNA Structure, Replication and Repair
chapter 30: RNA Structure, Synthesis and Processing
chapter 31: Protein Synthesis
chapter 32: Regulation of Gene Expression
chapter 33: Biotechnology and Human Disease
Lippincott’s Illustrated Reviews: Biochemistry 5th edition by Richard A. Harvey
Glycolysis (from glycose, an older term for glucose + -lysis degradation) is the metabolic pathway that converts glucose C6H12O6, into pyruvate, CH3COCOO− + H+. The free energy released in this process is used to form the high-energy compounds ATP (adenosine triphosphate) and NADH (reduced nicotinamide adenine dinucleotide).
Glycolysis is a determined sequence of ten enzyme-catalyzed reactions. The intermediates provide entry points to glycolysis. For example, most monosaccharides, such as fructose and galactose, can be converted to one of these intermediates. The intermediates may also be directly useful. For example, the intermediate dihydroxyacetone phosphate (DHAP) is a source of the glycerol that combines with fatty acids to form fat.
Glycolysis occurs, with variations, in nearly all organisms, both aerobic and anaerobic. The wide occurrence of glycolysis indicates that it is one of the most ancient known metabolic pathways. Indeed, the reactions that constitute glycolysis and its parallel pathway, the pentose phosphate pathway, occur metal-catalyzed under conditions of the Archean ocean also in the absence of enzymes. Glycolysis could thus have originated from chemical constraints of the prebiotic world.
Glycolysis occurs in most organisms in the cytosol of the cell. The most common type of glycolysis is the Embden–Meyerhof–Parnas (EMP pathway), which was discovered by Gustav Embden, Otto Meyerhof, and Jakub Karol Parnas. Glycolysis also refers to other pathways, such as the Entner–Doudoroff pathway and various heterofermentative and homofermentative pathways. However, the discussion here will be limited to the Embden–Meyerhof–Parnas pathway.
The entire glycolysis pathway can be separated into two phases:
The Preparatory Phase – in which ATP is consumed and is hence also known as the investment phase
The Pay Off Phase – in which ATP is produced.
DNA replication is the process of producing two identical replicas from one original DNA molecule. This biological process occurs in all living organisms and is the basis for biological inheritance. DNA is made up of two strands and each strand of the original DNA molecule serves as template for the production of the complementary strand, a process referred to as semiconservative replication. Cellular proofreading and error-checking mechanisms ensure near perfect fidelity for DNA replication.
In a cell, DNA replication begins at specific locations, or origins of replication, in the genome.Unwinding of DNA at the origin and synthesis of new strands results in replication forks growing bidirectional from the origin. A number of proteins are associated with the replication fork which helps in terms of the initiation and continuation of DNA synthesis. Most prominently, DNA polymerase synthesizes the new DNA by adding complementary nucleotides to the template strand.
DNA replication can also be performed in vitro (artificially, outside a cell). DNA polymerases isolated from cells and artificial DNA primers can be used to initiate DNA synthesis at known sequences in a template DNA molecule. The polymerase chain reaction (PCR), a common laboratory technique, cyclically applies such artificial synthesis to amplify a specific target DNA fragment from a pool of DNA.
A spliceosome is a large and complex molecular machine found primarily within the splicing speckles of the cell nucleus of eukaryotic cells. The spliceosome is assembled from snRNPs and protein complexes. The spliceosome removes introns from a transcribed pre-mRNA, a kind of primary transcript. This process is generally referred to as splicing. Only eukaryotes have spliceosomes and metazoans have a second spliceosome, the minor spliceosome.
The citric acid cycle – also known as the tricarboxylic acid cycle (TCA cycle), or the Krebs cycle, – is a series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetate derived from carbohydrates, fats and proteins into carbon dioxide and chemical energy in the form of adenosine triphosphate (ATP). In addition, the cycle provides precursors of certain amino acids as well as the reducing agent NADH that is used in numerous other biochemical reactions. Its central importance to many biochemical pathways suggests that it was one of the earliest established components of cellular metabolism and may have originated abiogenically.
The name of this metabolic pathway is derived from citric acid (a type of tricarboxylic acid) that is consumed and then regenerated by this sequence of reactions to complete the cycle. In addition, the cycle consumes acetate (in the form of acetyl-CoA) and water, reduces NAD+ to NADH, and produces carbon dioxide as a waste byproduct. The NADH generated by the TCA cycle is fed into the oxidative phosphorylation (electron transport) pathway. The net result of these two closely linked pathways is the oxidation of nutrients to produce usable chemical energy in the form of ATP.
In eukaryotic cells, the citric acid cycle occurs in the matrix of the mitochondrion. In prokaryotic cells, such as bacteria which lack mitochondria, the TCA reaction sequence is performed in the cytosol with the proton gradient for ATP production being across the cell's surface (plasma membrane) rather than the inner membrane of the mitochondrion.
How the NAD+ Works
Nicotinamide adenine dinucleotide, abbreviated NAD+, is a coenzyme found in all living cells. The compound is a dinucleotide, since it consists of two nucleotides joined through their phosphate groups: with one nucleotide containing an adenosine ring, and the other containing nicotinamide.
In metabolism, NAD+ is involved in redox reactions, carrying electrons from one reaction to another. The coenzyme is therefore found in two forms in cells: NAD+ is an oxidizing agent – it accepts electrons from other molecules and becomes reduced, this reaction forms NADH, which can then be used as a reducing agent to donate electrons. These electron transfer reactions are the main function of NAD+. However, it is also used in other cellular processes, notably as a substrate of enzymes that add or remove chemical groups from proteins, in posttranslational modifications. Due to the importance of these functions, the enzymes involved in NAD+ metabolism are targets for drug discovery.
In organisms, NAD+ can be synthesized from scratch (de novo) from the amino acids tryptophan or aspartic acid. Alternatively, components of the coenzymes are taken up from food as the vitamin called niacin. Similar compounds are released by reactions that break down the structure of NAD+. These preformed components then pass through a salvage pathway that recycles them back into the active form. Some NAD+ is also converted into nicotinamide adenine dinucleotide phosphate (NADP+); the chemistry of this related coenzyme is similar to that of NAD+, but it has different roles in metabolism.
Nicotinamide adenine dinucleotide is a dinucleotide since it consists of two nucleotides joined by a pair of bridging phosphate groups. The nucleotides consist of ribose rings, one with adenine attached to the first carbon atom (the 1' position) and the other with nicotinamide at this position. The nicotinamide group can be attached in two orientations to this anomeric carbon atom, due to these two possible structures, the compound exists as two diastereomers. It is the β-nicotinamide diastereomer of NAD+ which is found in organisms. These nucleotides are joined together by a bridge of two phosphate groups through the 5' carbons. In metabolism the compound accepts or donates electrons in redox reactions.Such reactions (summarized in formula below) involve the removal of two hydrogen atoms from the reactant (R), in the form of a hydride ion, and a proton (H+). The proton is released into solution, while the reductant RH2 is oxidized and NAD+ reduced to NADH by transfer of the hydride to the nicotinamide ring. RH2 + NAD+ → NADH + H+ + R From the hydride electron pair, one electron is transferred to the positively-charged nitrogen of the nicotinamide ring of NAD+, and the second hydrogen atom transferred to the C4 carbon atom opposite this nitrogen. The midpoint potential of the NAD+/NADH redox pair is −0.32 volts, which makes NADH a strong reducing agent. The reaction is easily reversible, when NADH reduces another molecule and is re-oxidized to NAD+. This means the coenzyme can continuously cycle between the NAD+ and NADH forms without being consumed. In appearance, all forms of this coenzyme are white amorphous powders that are hygroscopic and highly water-soluble. The solids are stable if stored dry and in the dark. Solutions of NAD+ are colorless and stable for about a week at 4 °C and neutral pH, but decompose rapidly in acids or alkalis. Upon decomposition, they form products that are enzyme inhibitors. Both NAD+ and NADH absorb strongly in the ultraviolet due to the adenine base. For example, peak absorption of NAD+ is at a wavelength of 259 nanometers (nm), with an extinction coefficient of 16,900 M-1cm-1. NADH also absorbs at higher wavelengths, with a second peak in UV absorption at 339 nm with an extinction coefficient of 6,220 M-1cm-1. This difference in the ultraviolet absorption spectra between the oxidized and reduced forms of the coenzymes at higher wavelengths makes it simple to measure the conversion of one to another in enzyme assays – by measuring the amount of UV absorption at 340 nm using a spectrophotometer. NAD+ and NADH also differ in their fluorescence. NADH in solution has an emission peak at 460 nm and a fluorescence lifetime of 0.4 nanoseconds, while the oxidized form of the coenzyme does not fluoresce. The properties of the fluorescence signal changes when NADH binds to proteins, so these changes can be used to measure dissociation constants, which are useful in the study of enzyme kinetics. These changes in fluorescence are also used to measure changes in the redox state of living cells, through fluorescence microscopy.
A DNA microarray (also commonly known as DNA chip or biochip) is a collection of microscopic DNA spots attached to a solid surface. Scientists use DNA microarrays to measure the expression levels of large numbers of genes simultaneously or to genotype multiple regions of a genome. Each DNA spot contains picomoles (10−12 moles) of a specific DNA sequence, known as probes (or reporters or oligos). These can be a short section of a gene or other DNA element that are used to hybridize a cDNA or cRNA (also called anti-sense RNA) sample (called target) under high-stringency conditions. Probe-target hybridization is usually detected and quantified by detection of fluorophore-, silver-, or chemiluminescence-labeled targets to determine relative abundance of nucleic acid sequences in the target.
Messenger RNA (mRNA) is a large family of RNA molecules that convey genetic information from DNA to the ribosome, where they specify the amino acid sequence of the protein products of gene expression. The existence of mRNA was first suggested by Jacques Monod and François Jacob. Following transcription of primary transcript mRNA (known as pre-mRNA) by RNA polymerase, processed, mature mRNA is translated into a polymer of amino acids: a protein, as summarized in the central dogma of molecular biology.
As in DNA, mRNA genetic information is in the sequence of nucleotides, which are arranged into codons consisting of three bases each. Each codon encodes for a specific amino acid, except the stop codons, which terminate protein synthesis. This process of translation of codons into amino acids requires two other types of RNA: Transfer RNA (tRNA), that mediates recognition of the codon and provides the corresponding amino acid, and ribosomal RNA (rRNA), that is the central component of the ribosome's protein-manufacturing machinery.
The light-dependent reactions take place on the thylakoid membranes. The inside of the thylakoid membrane is called the lumen, and outside the thylakoid membrane is the stroma, where the light-independent reactions take place. The thylakoid membrane contains some integral membrane protein complexes that catalyze the light reactions. There are four major protein complexes in the thylakoid membrane: Photosystem II (PSII), Cytochrome b6f complex, Photosystem I (PSI), and ATP synthase. These four complexes work together to ultimately create the products ATP and NADPH.
The two photosystems absorb light energy through pigments - primarily the chlorophylls, which are responsible for the green color of leaves. The light-dependent reactions begin in photosystem II. When a chlorophyll a molecule within the reaction center of PSII absorbs a photon, an electron in this molecule attains a higher energy level. Because this state of an electron is very unstable, the electron is transferred from one to another molecule creating a chain of redox reactions, called an electron transport chain (ETC). The electron flow goes from PSII to cytochrome b6f to PSI. In PSI, the electron gets the energy from another photon. The final electron acceptor is NADP. In oxygenic photosynthesis, the first electron donor is water, creating oxygen as a waste product. In anoxygenic photosynthesis various electron donors are used.
Cytochrome b6f and ATP synthase work together to create ATP. This process is called photophosphorylation, which occurs in two different ways. In non-cyclic photophosphorylation, cytochrome b6f uses the energy of electrons from PSII to pump protons from the stroma to the lumen. The proton gradient across the thylakoid membrane creates a proton-motive force, used by ATP synthase to form ATP. In cyclic photophosphorylation, cytochrome b6f uses the energy of electrons from not only PSII but also PSI to create more ATP and to stop the production of NADPH. Cyclic phosphorylation is important to create ATP and maintain NADPH in the right proportion for the light-independent reactions.
The net-reaction of all light-dependent reactions in oxygenic photosynthesis is:
2H
2O + 2NADP+
+ 3ADP + 3Pi → O
2 + 2NADPH + 3ATP
The two photosystems are protein complexes that absorb photons and are able to use this energy to create an electron transport chain. Photosystem I and II are very similar in structure and function. They use special proteins, called light-harvesting complexes, to absorb the photons with very high effectiveness. If a special pigment molecule in a photosynthetic reaction center absorbs a photon, an electron in this pigment attains the excited state and then is transferred to another molecule in the reaction center. This reaction, called photoinduced charge separation, is the start of the electron flow and is unique because it transforms light energy into chemical forms.
The light-independent reactions of photosynthesis are chemical reactions that convert carbon dioxide and other compounds into glucose. These reactions occur in the stroma, the fluid-filled area of a chloroplast outside of the thylakoid membranes. These reactions take the products(ATP and NADPH)of light-dependent reactions and perform further chemical processes on them. There are three phases to the light-independent reactions, collectively called the Calvin cycle: carbon fixation, reduction reactions, and ribulose 1,5-bisphosphate (RuBP) regeneration.
Despite its name, this process occurs only when light is available. Plants do not carry out the Calvin cycle by night. They, instead, release sucrose into the phloem from their starch reserves. This process happens when light is available independent of the kind of photosynthesis (C3 carbon fixation, C4 carbon fixation, and Crassulacean Acid Metabolism); CAM plants store malic acid in their vacuoles every night and release it by day in order to make this process work.
