This interactive exercise is intended to help you understand why glycolysis has evolved to the form that we can observe in living cells and how it is so efficient that it seems to resemble a designed process. THIS IS NOT A QUIZ - when presented with options you should choose the wrong answers to gain maximum understanding.
This page explains the formation of Acetyl Co-enzyme A which is key to the synthesis of many organic molecules in cells. An acetyl group is a simple two-carbon-atom molecule which is sufficiently reactive to make it possible to use as a building block for larger carbon skeletons.
A large number of molecules that are synthesised in cells are built from two-carbon acetyl groups. An acetyl group derives from ethanoate (acetate) and is named acetyl when it forms a group within a larger molecule. Instead of using free acetate molecules the cell 'activates' the molecule by attaching it to Coenzyme A (CoA).
The acetyl group can derive from pyruvate (and ultimately from monosaccharides if that is the main 'food' for the cell). The two processes of oxidising/decarboxylating pyruvate and attaching the resulting acetyl group to CoA are coupled.
Oxidative decarboxylation is catalyzed by the pyruvate dehydrogenase complex. It is a multimeric assembly of three kinds of enzyme that implements the process in four steps. The animation shows all four steps in sequence and data sheets follow.
Living cells can process certain sugar molecules, rearranging their atoms and this process can supply energy to the cell to power growth and other functions. This process is called glycolysis. Glycolysis evolved billions of years ago when there was no oxygen in the earth's atmosphere and it was therefore impossible for cells to gain energy from the oxidation of sugar molecules using oxygen. Later when oxygen was produced as a byproduct of photosynthesis cells evolved to utilise oxygen to oxidise the product of glycolysis and capture much more energy.
Biochemistry text books will give you the details surrounding the metabolic pathway, glycolysis. This introduction avoids the detail and the individual steps and gives an overview of what glycolysis is all about. I've tried to keep the text short and sweet and to use animations to avoid a lot of verbose explanation.
The monosaccharide browser allows you to view space filling Fischer projections of monosaccharides. You can edit the structure and discover the correct name or you can select names from the classified index to discover the structure. The structure can be edited by choosing between aldose/ketose, number of carbon atoms between 3 and 6 and by clicking on carbon atoms to alter chirality.
The Monosaccharide Browser can be used as a study aid in various ways.
•Make a random monosaccharide by clicking on the controls with the mouse but cover the name with your hand - practice naming the sugar before you reveal the correct name. •Pick the name of a monosacharide and build it by selecting the correct type of sugar and by clicking on the chiral carbon atoms. •Pick two monosaccharides from a metabolic pathway, select the name of the first sugar and then work out which structural changes you need to make to convert it into the second sugar. (E.g. D-Glucose to D-Galactose, D-Glucose to D-Fructose etc.) •Look at the cyclic structures of monosaccharides in your text book and use the Monosaccharide browser to build the straight chain form.
These activities could be more effective with a study partner.
You can browse the eleven steps of anaerobic glycolysis and view three kinds of information: reaction data (the enzyme, reaction type and thermodynamic data), equation and animation.
Glükoosi anaeroobne lagundamine etappide kaupa. Üleminekud, reaktsiooni vaheühendid, üldinfo ning lühike animatsioon molekulimudelitega. Sobib ainevahetuse käsitlemisel üldbioloogias.
You can browse the eleven steps of anaerobic glycolysis and view three kinds of information: reaction data (the enzyme, reaction type and thermodynamic data), equation and animation.
These pages show the steps of the metabolic pathway called the Tricarboxylic Acid (TCA) cycle. Otherwise known as the citric acid cycle and the Krebs cycle. Data sheets, reaction diagrams and animations are provided for each step.
Krebs cycle or the citric acid cycle or tricarboxylic acid cycle,occurs in mitochondria, is the common pathway to completely oxidize fuel molecules which mostly is acetyl CoA ,the product from the oxidative decarboxylation of pyruvate. It enters the cycle and passes ten steps of reactions that yield energy and CO2 You can browse the ten steps of reactions through three strands: fact sheet gives the name of enzyme, reaction type,mechanism and prosthetic group; reaction shows the structure of substrate and product(s) and animation presents a short movie clip showing the reaction.
No restrictions on your remixing, redistributing, or making derivative works.
Give credit to the author, as required.
Your remixing, redistributing, or making derivatives works comes with some
restrictions, including how it is shared.
Your redistributing comes with some restrictions. Do not remix or make
derivative works.
Copyrighted materials, available under Fair Use and the TEACH Act for US-based
educators, or other custom arrangements. Go to the resource provider to see
their individual restrictions.
