 | Cellular Metabolism, Pathways & Feedback Cellular Metabolism, Pathways & Feedback The sum of all chemical changes that take place in a cell through which energy and basic components are provided for essential processes, including the synthesis of new molecules and the breakdown and removal of others. |
 | The Calvin Cycle or "Dark" Reactions (Photosynthesis) Watch Carbon Dioxide become sugar! Overview During photosynthesis, light energy is used to generate chemical free energy, stored in glucose. The light-independent Calvin cycle, also (misleadingly) known as the "dark reaction" or "dark stage", uses the energy from short-lived electronically-excited carriers to convert carbon dioxide and water into organic compounds that can be used by the organism (and by animals which feed on it). This set of reactions is also called carbon fixation. The key enzyme of the cycle is called RuBisCO. In the following equations, the chemical species (phosphates and carboxylic acids) exist in equilibria among their various ionized states as governed by the pH. The enzymes in the Calvin cycle are functionally equivalent to many enzymes used in other metabolic pathways such as gluconeogenesis and the pentose phosphate pathway, but they are to be found in the chloroplast stroma instead of the cell cytoplasm, separating the reactions. They are activated in the light (which is why the name "dark reaction" is misleading), and also by products of the light-dependent reaction. These regulatory functions prevent the Calvin cycle from operating in reverse to respiration, which would create a continuous cycle of carbon dioxide being reduced to carbohydrates, and carbohydrates being respired to carbon dioxide. Energy (in the form of ATP) would be wasted in carrying out these reactions that have no net productivity. The sum of reactions in the Calvin cycle is the following: 3 CO2 + 6 NADPH + 5 H2O + 9 ATP → C3H5O3-PO32- + 2 H+ + 6 NADP+ + 9 ADP + 8 Pi OR 3 CO2 + 6 C21H29N7O17P3 + 5 H2O + 9 C10H16N5O13P3 → C3H5O3-PO32- + 2 H+ + 6 NADP+ + 9 C10H15N5O10P2 + 8 Pi It should be noted that hexose (six carbon) sugars are not a product of the Calvin cycle. Although many texts list a product of photosynthesis as C6H12O6, this is mainly a convenience to counter the equation of respiration, where six-carbon sugars are oxidized in mitochondria. The carbohydrate products of the Calvin Cycle are three-carbon sugar phosphate molecules, or "triose phosphates," specifically, glyceraldehyde-3-phosphate. |
 | The Matrix debunking evolution 3/8 An April 2008 article in Science News magazine adds: "To make sense of the genome, systems biologists think in terms of networks. If two kinds of proteins or other biological molecules interact, they are connected on the network." "These network diagrams... show how individual pathways crisscross to form a tangled web. Each protein in a pathway can interact with molecules in other pathways, sometimes dozens of them." Additionally, "systems biologists produce complex maps of how genes and proteins interact, and these maps help scientists analyze results from drug screening." "Cells 'talk' to each other by passing chemical signals back and forth. They also sense their physical surroundings through proteins on their surfaces called integrins. All these cues serve to orient the cells in the body and inform them about how to behave so that they cooperate with the rest of the cells in the tissue." "The cells are not complete by themselves. They need signals from outside," says Mina J. Bissell of Lawrence Berkeley National Laboratory. "The unit of function literally is the tissue."-- Patrick Barry. April 5, 2008. You, in a dish: cultured human cells could put lab animals out of work for chemical and drug testing. Science News, Vol. 173, No. 14, pp. 218-220. Only a small portion of a creature's DNA codes for proteins (around 1.5% in humans). In the 1970s, evolutionists began calling the rest of it "junk DNA", saying this collection of useless evolutionary debris showed there was no intelligent design involved. Decades later, researchers are finding that different parts of the "junk" do vital work. Some of this DNA plays a role in turning genes on and off at the right moments in a developing embryo7. Other bits separate coding and regulating sections, like punctuation marks in writing, so that DNA is not a long run-on sentence8. Other bits called Alu elements, found only in primates, can be spliced in or out during RNA processing to make different versions of the same gene. This "alternative splicing" may explain why the approximately 25,000 genes in the human genome produce about 90,000 proteins9. The number of protein-coding genes in organisms ranging from plants to flies to humans is fairly similar. The largest differences in their genomes are the amounts of the other DNA they have. The "junk" label discouraged research into this part of the genome for many years; who would want to waste their time studying it? Consequently, much remains to be discovered about this DNA. Yet already we know that a lot of it is not the junk evolutionists were counting on. |
 | Chandrayaan-1, India's first mission to Moon (Part 1/3) Courtesy ISRO: "THE MOON" with the history of the early solar system etched on it beckons mankind from time immemorial to admire its marvels and discover its secrets. Understanding the moon provides a pathway to unravel the early evolution of the solar system and that of the planet earth. Through the ages, the Moon, our closest celestial body has aroused curiosity in our mind much more than any other objects in the sky. Scientific Objectives: - The Chandrayaan-1 mission is aimed at high-resolution remote sensing of the moon in visible, near infrared(NIR), low energy X-rays and high-energy X-ray regions. Specifically the objectives will be - To prepare a three-dimensional atlas (with a high spatial and altitude resolution of 5-10m) of both near and far side of the moon. - To conduct chemical and mineralogical mapping of the entire lunar surface for distribution of elements such as Magnesium, Aluminum, Silicon, Calcium, Iron and Titanium with a spatial resolution of about 25 km and high atomic number elements such as Radon, Uranium & Thorium with a spatial resolution of about 20 km. - Simultaneous photo geological and chemical mapping will enable identification of different geological units, which will test the early evolutionary history of the moon and help in determining the nature and stratigraphy of the lunar crust. Mission Objectives: - To realise the mission goal of harnessing the science payloads, lunar craft and the launch vehicle with suitable ground support systems including DSN station. - To realise the integration and testing, launching and achieving lunar polar orbit of about 100 km, in-orbit operation of experiments, communication/ telecommand, telemetry data reception, quick look data and archival for scientific utilization by identified group of scientists. GROUND SEGMENT FOR CHANDRAYAAN-1 MISSION, comprises of three major elements: The Ground Station Network including the Indian Deep Space Network (IDSN), Mission Operations Complex (MOX)and Indian Space Science Data Centre (ISSDC). This trio of ground facility ensures the success of the mission by providing to and fro conduit of communication, securing good health of the spacecraft, maintaining the orbit and attitude to the requirements of the mission and conducting payload operations. The ground segment is also responsible for making the science data available for the Payload Scientists along with auxiliary information, in addition to archiving of payload and spacecraft data. Payload Operation Centres (POCs) also form a part of the Ground Segment. |
 | Chandrayaan-1, India's first mission to Moon (Part 2/3) Courtesy ISRO: "THE MOON" with the history of the early solar system etched on it beckons mankind from time immemorial to admire its marvels and discover its secrets. Understanding the moon provides a pathway to unravel the early evolution of the solar system and that of the planet earth. Through the ages, the Moon, our closest celestial body has aroused curiosity in our mind much more than any other objects in the sky. Scientific Objectives: - The Chandrayaan-1 mission is aimed at high-resolution remote sensing of the moon in visible, near infrared(NIR), low energy X-rays and high-energy X-ray regions. Specifically the objectives will be - To prepare a three-dimensional atlas (with a high spatial and altitude resolution of 5-10m) of both near and far side of the moon. - To conduct chemical and mineralogical mapping of the entire lunar surface for distribution of elements such as Magnesium, Aluminum, Silicon, Calcium, Iron and Titanium with a spatial resolution of about 25 km and high atomic number elements such as Radon, Uranium & Thorium with a spatial resolution of about 20 km. - Simultaneous photo geological and chemical mapping will enable identification of different geological units, which will test the early evolutionary history of the moon and help in determining the nature and stratigraphy of the lunar crust. Mission Objectives: - To realise the mission goal of harnessing the science payloads, lunar craft and the launch vehicle with suitable ground support systems including DSN station. - To realise the integration and testing, launching and achieving lunar polar orbit of about 100 km, in-orbit operation of experiments, communication/ telecommand, telemetry data reception, quick look data and archival for scientific utilization by identified group of scientists. GROUND SEGMENT FOR CHANDRAYAAN-1 MISSION, comprises of three major elements: The Ground Station Network including the Indian Deep Space Network (IDSN), Mission Operations Complex (MOX)and Indian Space Science Data Centre (ISSDC). This trio of ground facility ensures the success of the mission by providing to and fro conduit of communication, securing good health of the spacecraft, maintaining the orbit and attitude to the requirements of the mission and conducting payload operations. The ground segment is also responsible for making the science data available for the Payload Scientists along with auxiliary information, in addition to archiving of payload and spacecraft data. Payload Operation Centres (POCs) also form a part of the Ground Segment. |
 | Chandrayaan-1, India's first mission to Moon (Part 3/3) Courtesy ISRO: "THE MOON" with the history of the early solar system etched on it beckons mankind from time immemorial to admire its marvels and discover its secrets. Understanding the moon provides a pathway to unravel the early evolution of the solar system and that of the planet earth. Through the ages, the Moon, our closest celestial body has aroused curiosity in our mind much more than any other objects in the sky. Scientific Objectives: - The Chandrayaan-1 mission is aimed at high-resolution remote sensing of the moon in visible, near infrared(NIR), low energy X-rays and high-energy X-ray regions. Specifically the objectives will be - To prepare a three-dimensional atlas (with a high spatial and altitude resolution of 5-10m) of both near and far side of the moon. - To conduct chemical and mineralogical mapping of the entire lunar surface for distribution of elements such as Magnesium, Aluminum, Silicon, Calcium, Iron and Titanium with a spatial resolution of about 25 km and high atomic number elements such as Radon, Uranium & Thorium with a spatial resolution of about 20 km. - Simultaneous photo geological and chemical mapping will enable identification of different geological units, which will test the early evolutionary history of the moon and help in determining the nature and stratigraphy of the lunar crust. Mission Objectives: - To realise the mission goal of harnessing the science payloads, lunar craft and the launch vehicle with suitable ground support systems including DSN station. - To realise the integration and testing, launching and achieving lunar polar orbit of about 100 km, in-orbit operation of experiments, communication/ telecommand, telemetry data reception, quick look data and archival for scientific utilization by identified group of scientists. GROUND SEGMENT FOR CHANDRAYAAN-1 MISSION, comprises of three major elements: The Ground Station Network including the Indian Deep Space Network (IDSN), Mission Operations Complex (MOX)and Indian Space Science Data Centre (ISSDC). This trio of ground facility ensures the success of the mission by providing to and fro conduit of communication, securing good health of the spacecraft, maintaining the orbit and attitude to the requirements of the mission and conducting payload operations. The ground segment is also responsible for making the science data available for the Payload Scientists along with auxiliary information, in addition to archiving of payload and spacecraft data. Payload Operation Centres (POCs) also form a part of the Ground Segment. |
 | Is Depleted Uranium As Safe As The Military Claims? DU Video Depleted Uranium (DU) General Awarness Training. Potential health effects of exposure to depleted uranium. In the kidneys, the proximal tubules (the main filtering component of the kidney) are considered to be the main site of potential damage from chemical toxicity of uranium. There is limited information from human studies indicating that the severity of effects on kidney function and the time taken for renal function to return to normal both increase with the level of uranium exposure. In a number of studies on uranium miners, an increased risk of lung cancer was demonstrated, but this has been attributed to exposure from radon decay products. Lung tissue damage is possible leading to a risk of lung cancer that increases with increasing radiation dose. However, because DU is only weakly radioactive, very large amounts of dust (on the order of grams) would have to be inhaled for the additional risk of lung cancer to be detectable in an exposed group. Risks for other radiation-induced cancers, including leukaemia, are considered to be very much lower than for lung cancer. Erythema (superficial inflammation of the skin) or other effects on the skin are unlikely to occur even if DU is held against the skin for long periods (weeks). No consistent or confirmed adverse chemical effects of uranium have been reported for the skeleton or liver. No reproductive or developmental effects have been reported in humans. Although uranium released from embedded fragments may accumulate in the central nervous system (CNS) tissue, and some animal and human studies are suggestive of effects on CNS function, it is difficult to draw firm conclusions from the few studies reported. Maximum radiation exposure limits and their limited application to uranium and depleted uranium. The International Basic Safety Standards, agreed by all applicable UN agencies in 1996, provide for radiation dose limits above normal background exposure levels. The general public should not receive a dose of more than 1 millisievert (mSv) in a year. In special circumstances, an effective dose of up to 5 mSv in a single year is permitted provided that the average dose over five consecutive years does not exceed 1 mSv per year. An equivalent dose to the skin should not exceed 50 mSv in a year. Occupational exposure should not exceed an effective dose of 20 mSv per year averaged over five consecutive years or an effective dose of 50 mSv in any single year. An equivalent dose to the extremities (hands and feet) or the skin should not surpass 500 mSv in a year. In case of uranium or DU intake, the radiation dose limits are applied to inhaled insoluble uranium-compounds only. For all other exposure pathways and the soluble uranium-compounds, chemical toxicity is the factor that limits exposure. About 98% of uranium entering the body via ingestion is not absorbed, but is eliminated via the faeces. Typical gut absorption rates for uranium in food and water are about 2% for soluble and about 0.2% for insoluble uranium compounds. The fraction of uranium absorbed into the blood is generally greater following inhalation than following ingestion of the same chemical form. The fraction will also depend on the particle size distribution. For some soluble forms, more than 20% of the inhaled material could be absorbed into blood. Of the uranium that is absorbed into the blood, approximately 70% will be filtered by the kidney and excreted in the urine within 24 hours; this amount increases to 90% within a few days. Creative Commons license: Attribution-NonCommercial-NoDerivs |
 | G Protein Receptor This animation describes what takes place with a G protein receptor. G Protein Coupled Receptors (GPCRs) are proteins embedded in the surface of cells. GPCRs comprise the largest superfamily of proteins in the body. More than 1,000 different GPCRs have been identified since the first receptors were cloned. These proteins receive chemical signals from outside the cell and pass the signal into the cell, so that the cell can respond to the signal. The structures of the endogenous ligands for GPCRs are exceptionally diverse. They include biogenic amines such as norephnephrine and serotonine, peptides, glycoproteins, lipids, nucleotides, ions, and proteases. The sensation of exogenous stimuli, such as light, odors, and taste, is also mediated by this class of receptors. Activation of the receptor causes an effector inside the cell to produce a second signal chemical, which eventually triggers the cell to react to the original external chemical signal. Andrea and Richard animated the signal process in this clip. A ligand, in this case Norepinepherine (NE), binds to the receptor and induces a conformational change. This conformational change activates the a/b complex. The complex is bound to GDP while it is inactive. GTP replaces GDP, thus activating the Alpha subunit. The activated Alpha subunit undergoes a conformational change and activates Adenylate Cyclase. Once the Adenylate Cyclase is activated, it is then able to convert ATP. The products of ATP conversion are c-AMP and two phosphate molecules. c-AMP is a second messenger used in many processes required for cell survival and growth. Future plans are to expand this animation to show the second messenger pathways, and further explain intracellular signaling in a variety of living processes. Created by: Andrea Dichele - Biomedical and Pharmaceutical Sciences StudentAndrea Dichele Class of 2006 Pharmacy Richard Wallace - Biomedical and Pharmaceutical Sciences StudentRichard Wallace Class of 2006 Pharmacy Doctor Rodgers - Biomedical and Pharmaceutical SciencesDr. Robert Rodgers Professor of Biomedical and Pharmaceutical Sciences Biomedical and Pharmaceutical Sciences College of Pharmacy Doctor Babson - Biomedical and Pharmaceutical SciencesDr. John Babson Associate Professor of Biomedical and Pharmaceutical Sciences College of Pharmacy |
 | Xtreme Hammer In this video, we discussed several important topics: carbohydrates, lipids, aqueous environment, photosynthesis, and Peter Mitchell. Carbohydrates, when broken down into glucose, provides energy for organisms. Lipids, commonly called fats, can be saturated(sold and room temperature) or unsaturated(liquid at room temperature). Organisms are composed of water, thus the systems and functions of all organisms are based on an aqueous environment. Photosynthesis is extremely important because it is the only energy forming pathway that can turn light energy into chemical energy. One of the most important scientific discoveries was done by Peter Mitchell. He discovered the chemiosmotic gradient, which is found in both the chloroplast and the mitochondrion and used to phosphorylate ADP + P into ATP. Though all of these elements may seem independent, when they are regarded as part of a whole biological system, they join together seamlessly to thoroughly explain how life really works. The Xtreme Hammer doll will be availiable to the highest bidder as a voodoo doll or a stress reliever during exam time. |
 | Get to Grips with Biochemistry (Glycolysis) http://get2grips.50webs.com Video based on the ebook Get to Grips with Biochemistry. Some FREE chapters can be downloaded from http://get2grips.50webs.com. 50 short chapters with short questions and answers taking you step by step through important biochemical pathways and chemical structures that you need to know to help you understand biochemistry and pass your exams ! |
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