Solutions to 7.014 Problem Set 1
... Prebiotic earth had an atmosphere that lacked oxygen, but was rich in H2, N2, CO2, H2O, and sulfurous gases. In the absence of O2 and O3, the UV light penetrated in far greater strength than it does now. Today, we have an atmosphere rich in oxygen and an ozone that protects us from the sun’s UV ligh ...
... Prebiotic earth had an atmosphere that lacked oxygen, but was rich in H2, N2, CO2, H2O, and sulfurous gases. In the absence of O2 and O3, the UV light penetrated in far greater strength than it does now. Today, we have an atmosphere rich in oxygen and an ozone that protects us from the sun’s UV ligh ...
Microbiology
... microbial carnitine metabolism was not described until more than 50 years later (Fraenkel & Friedman, 1957). In the intervening years, microbiologists have described the roles for carnitine in bacteria, where it can be used as a final electron acceptor, a compatible solute, or as a sole carbon, nitr ...
... microbial carnitine metabolism was not described until more than 50 years later (Fraenkel & Friedman, 1957). In the intervening years, microbiologists have described the roles for carnitine in bacteria, where it can be used as a final electron acceptor, a compatible solute, or as a sole carbon, nitr ...
7.013 Spring 2005 Problem Set 1Solutions
... You have identified a new, rapidly reproducing species of dog that you have named the “mitbull”. The mitbull is diploid and two autosomal chromosomes are shown. One chromosome carries gene A with two alleles designated A and a. The other chromosome carries gene B with two alleles designated B and b. ...
... You have identified a new, rapidly reproducing species of dog that you have named the “mitbull”. The mitbull is diploid and two autosomal chromosomes are shown. One chromosome carries gene A with two alleles designated A and a. The other chromosome carries gene B with two alleles designated B and b. ...
Glycerol transport and phosphoenolpyruvate
... play an important role in the regulation of glycerol metabolism in numerous bacteria. The mechanisms involved in this regulation are different in Gram-positive and Gram-negative bacteria, but they are both mediated via glycerol kinase. In Gram-negative bacteria such as Escherichia coli or Salmonella ...
... play an important role in the regulation of glycerol metabolism in numerous bacteria. The mechanisms involved in this regulation are different in Gram-positive and Gram-negative bacteria, but they are both mediated via glycerol kinase. In Gram-negative bacteria such as Escherichia coli or Salmonella ...
Problem Set
... organic chemistry. In 1858 he showed that carbon is tetravalent and could form long chains. "One night in 1865 Kekule dreamed of the benzene molecule as a snake biting its tail while in whirling motion. From that vision his concept of the six-carbon benzene ring was born". Factual dream or not, Keku ...
... organic chemistry. In 1858 he showed that carbon is tetravalent and could form long chains. "One night in 1865 Kekule dreamed of the benzene molecule as a snake biting its tail while in whirling motion. From that vision his concept of the six-carbon benzene ring was born". Factual dream or not, Keku ...
No Slide Title
... irreversible deamination of AMP to IMP (inosine monophosphate), a precursor of uric acid. – depletion of tissue ATP occurs through massive degradation to uric acid, and the impairment of regeneration by oxidative phosphorylation in the mitochondria because of inorganic phosphate depletion (lost to p ...
... irreversible deamination of AMP to IMP (inosine monophosphate), a precursor of uric acid. – depletion of tissue ATP occurs through massive degradation to uric acid, and the impairment of regeneration by oxidative phosphorylation in the mitochondria because of inorganic phosphate depletion (lost to p ...
Thiamine: an overview
... Thiamine is released by the action of phosphates and pyrophosphates in the upper small intestine. At low concentrations the process is carrier mediated and at higher concentrations, absorption occurs via passive diffusion. Active transport is greatest in the jejunum and ileum (it is inhibited by alc ...
... Thiamine is released by the action of phosphates and pyrophosphates in the upper small intestine. At low concentrations the process is carrier mediated and at higher concentrations, absorption occurs via passive diffusion. Active transport is greatest in the jejunum and ileum (it is inhibited by alc ...
EFFECTS OF BIOREACTOR OPERATION PARAMETERS ON
... oxygen uptake rates and the liquid phase mass transfer coefficient values were determined. The highest β-lactamase activity was obtained at 0.5 vvm 500 min-1 and at 0.2 vvm 500 min-1 conditions as ca. A=90 U cm-3 while the highest cell concentration was obtained as Cx=0.67 kg m-3 at 0.5 vvm 750 min ...
... oxygen uptake rates and the liquid phase mass transfer coefficient values were determined. The highest β-lactamase activity was obtained at 0.5 vvm 500 min-1 and at 0.2 vvm 500 min-1 conditions as ca. A=90 U cm-3 while the highest cell concentration was obtained as Cx=0.67 kg m-3 at 0.5 vvm 750 min ...
Carnitine-Metabolism and Functions
... ascorbic acid most likely protects the ferrous ions and enzyme sulfhydryl (-SH) groups from oxidation. An activating effect of catalase (EC 1.11.1.6) in vitro is probably explained by the removal of inactivating hydrogen peroxide formed by spontaneous oxidation of ascorbic acid and ferrous ions (243 ...
... ascorbic acid most likely protects the ferrous ions and enzyme sulfhydryl (-SH) groups from oxidation. An activating effect of catalase (EC 1.11.1.6) in vitro is probably explained by the removal of inactivating hydrogen peroxide formed by spontaneous oxidation of ascorbic acid and ferrous ions (243 ...
What is Cholesterol?......cont. - Home
... - Cholesterol consists of four rings. These rings are identified by the first four letters of the alphabet. - The carbons of cholesterol which are 27 are numbered in the sequence shown in figure 1 . ...
... - Cholesterol consists of four rings. These rings are identified by the first four letters of the alphabet. - The carbons of cholesterol which are 27 are numbered in the sequence shown in figure 1 . ...
Polynucleotide Phosphorylase and Mitochondrial
... enzymes do not directly reduce AsV to AsIII, but rather they convert AsV into an arsenylated metabolite (i.e., an AsV ester or anhydride), in which the pentavalent arsenic is much more reducible by thiol compounds than in the inorganic form (Gregus et al., 2009; Németi and Gregus, 2009b). Isolated ...
... enzymes do not directly reduce AsV to AsIII, but rather they convert AsV into an arsenylated metabolite (i.e., an AsV ester or anhydride), in which the pentavalent arsenic is much more reducible by thiol compounds than in the inorganic form (Gregus et al., 2009; Németi and Gregus, 2009b). Isolated ...
Chapter 1 - York University
... reasons which will described later (Section 3.5) and ‘CH2O’ is put into italics to emphasize that it is not a real compound but something with the same general structure as a carbohydrate. Sometimes the whole equation is multiplied by 6 so that the non-existent CH2O becomes C6H12O6. This has the adv ...
... reasons which will described later (Section 3.5) and ‘CH2O’ is put into italics to emphasize that it is not a real compound but something with the same general structure as a carbohydrate. Sometimes the whole equation is multiplied by 6 so that the non-existent CH2O becomes C6H12O6. This has the adv ...
Structure and Function of Thymosin β4
... digestion gave two peptides which lacked a free α-amino group. These two peptides were deduced to be a part of the N-terminus region. The tryptic digestion also produced a peptide which lacks a lysine residue and was therefore placed in the C-terminus region. The side chains were assigned their posi ...
... digestion gave two peptides which lacked a free α-amino group. These two peptides were deduced to be a part of the N-terminus region. The tryptic digestion also produced a peptide which lacks a lysine residue and was therefore placed in the C-terminus region. The side chains were assigned their posi ...
View/Open
... improved growth rate and feed conversion of finishing beef cattle compared to when diets containing corn grain were fed. This performance improvement is often a result of reduced sub-acute acidosis and fewer problems with cattle going “off-feed”. Starch in corn grain is more likely to cause acidosis ...
... improved growth rate and feed conversion of finishing beef cattle compared to when diets containing corn grain were fed. This performance improvement is often a result of reduced sub-acute acidosis and fewer problems with cattle going “off-feed”. Starch in corn grain is more likely to cause acidosis ...
Analysis of the Arabidopsis rsr4-1/pdx1
... plants, the Arabidopsis thaliana salt-sensitive mutant salt overly sensitive4 (sos4) has been described that carries a mutation in a pdxK homolog (Shi et al., 2002; Shi and Zhu, 2002). Loss of SOS4 leads to altered root hair development and increased sensitivities toward Naþ, Kþ, and Liþ ions, which ...
... plants, the Arabidopsis thaliana salt-sensitive mutant salt overly sensitive4 (sos4) has been described that carries a mutation in a pdxK homolog (Shi et al., 2002; Shi and Zhu, 2002). Loss of SOS4 leads to altered root hair development and increased sensitivities toward Naþ, Kþ, and Liþ ions, which ...
Auxin: Regulation, Action, and Interaction
... auxin through the plant, the emerging view of auxin-signalling mechanisms, and several interactions between auxin and other phytohormones. Though many natural and synthetic compounds exhibit auxin-like activity in bioassays, indole-3-acetic acid (IAA) is recognized as the key auxin in most plants. I ...
... auxin through the plant, the emerging view of auxin-signalling mechanisms, and several interactions between auxin and other phytohormones. Though many natural and synthetic compounds exhibit auxin-like activity in bioassays, indole-3-acetic acid (IAA) is recognized as the key auxin in most plants. I ...
Biosynthesis
Biosynthesis (also called biogenesis or anabolism) is a multi-step, enzyme-catalyzed process where substrates are converted into more complex products in living organisms. In biosynthesis, simple compounds are modified, converted into other compounds, or joined together to form macromolecules. This process often consists of metabolic pathways. Some of these biosynthetic pathways are located within a single cellular organelle, while others involve enzymes that are located within multiple cellular organelles. Examples of these biosynthetic pathways include the production of lipid membrane components and nucleotides.The prerequisite elements for biosynthesis include: precursor compounds, chemical energy (e.g. ATP), and catalytic enzymes which may require coenzymes (e.g.NADH, NADPH). These elements create monomers, the building blocks for macromolecules. Some important biological macromolecules include: proteins, which are composed of amino acid monomers joined via peptide bonds, and DNA molecules, which are composed of nucleotides joined via phosphodiester bonds.