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Biological Chemistry

Net charge on peptide

Consider this peptide: Phe-Glu-Ser-Met What is the net charge of this peptide at ph=1 What is the net charge of this peptide at ph=7

Number of Glucose Molecles in Mycoplasma

Mycoplasmas are the smallest living cells. They are spherical and have a diameter of about 0.33 μm (radius of mycoplasmas = 0.165 μm)a. (a)Glucose is the major energy source of mycoplasma cells. Its concentration within such cells is 0.1 mM. Calculate the number of glucose molecules within a single cell. (b) The fi

Enzyme and Endocrine Disruptor Clarifications

Which of these apply to Enzymes A. The majority of chemical reactions in our bodies do not require enzymes. B. Enzymes are functional proteins C. Enzymes get used up as part of a reaction D. Cyto chrome P-450 is an example of an enzyme that helps to oxidize chemicals in the body. E. Biotransformation of toxins could not o


A friend insists that all mutagens are dangerous. How would you respond?

An Investigation of Fermentaion In Yeast: Determination of Ethanol Uptake

I carried out the practical shown in the attachment, and am struggling with the calculations, Can anyone please explain what I need to do? As there are different calculations for different bits I am submitting separate post for each bit. Is there anyone who can show my how to determine ethanol formed? The model answers from

Determining Km and Vmax

I have made a lineweaver-burk graph with some data, but I don't know how to determine Vmax and Km from it? Would you please give me an example of how to do it. Please make a lineweaver-graph with some values and tell me how to determine Km and Vmax. I can figure out the slope from the graph, but cannot figure out Y and x in Y

Using Beer's Law to Calculate Glucose Concentrations

I have a series of protein free patient blood samples at time; 0, 30, 60, 90, 120, 180 mins. I also have a standard sample. I have measured the absorbance of these samples; 0.655, 0.717, 0.689, 0.430, 0.852, 0.477 respectively. Standard sample 0.760 The glucose concentration in the standard test tube is 0.278 mmole/L. Using Beer

Biochemistry and Molecular Characteristics

Question #1: (1 point) In the urea cycle, the molecule that is synthesized in the cytosol and transported to the mitochondrial matrix for subsequent reactions is a.) citrulline b.) ornithine c.) argininosuccinate d.) aspartate e.) carbamoyl-phosphate Question #2: (1 point) Inosine 5'-phosphate is a precursor to which

Standard reduction potential for fumarate

The standard reduction potential (Eo') for the reduction of fumarate is +0.03V. The Eo' for the reduction of FAD in a given protein that accepts the electrons from succinate is -0.40V. Given the reaction: succinate + FAD==fumarate + FADH2 Caluculate Eo' for the reation

Calculation of Fractional Saturation of Protein in GDP / GTP

Guanyl nucleotide regulatory proteins (N) alter cell function based on the type of guanyl nucleotide occupying the nucleotide site on the protein. The affinity of this site for guanyl nucleotides is to a certain extent under hormonal control. Given a Ka of the site for guanyl nucleotides of 3 x 10^7 M in the presence of hormon

Energy Required by Na-K Pump to Move 2 Na+ and 3 K+ Ions

Problem: How much energy is needed for the Na/K pump to move 3 Na out and 2 K in when Nai (Na inside)= 9.2mM, Nao (outside)= 115, Ki (K inside)= 135mM and Ko (K outside)= 3mM? Include the effects of membrane potential; it will have to be calculated based on the given ion concentrations and PNa/Pk of 0.013.

Calculation of pH Gradient Required to Convert ADP to ATP

Calculate the pH gradient across the inner mitochondrial membrane that is necessary to drive the ATPase reaction in the direction of ATP synthesis under steady state conditions at 25°C where ATP=10^-5 M ADP= 10^-3 M Pi=2 x 10^-2 M Also- do not ignore the effect of the membrane potential!

Beta-Oxidation of Odd and Even Carbon Fatty Acids

1 BCH-100 Fall 2007 BLH #13 (4 points) Question #1: (0.8 point) How many acetyl CoA's will come from a 12 carbon acyl-CoA? a.) 5 b.) 6 c.) 7 d.) 12 e.) none Question #2: (0.8 point) How many acetyl CoA's will come from a 13 carbon acyl-CoA? a.) 5 b.) 6 c.) 7 d.) 12 e.) none Question #3: (0.8 point) How many p

Flow of carbon atom from triacylglycerols to glucose

Although animals do not have glyoxylate cycle its is still possible to find radioactively labelled carbon atoms from triacylglycerols incorporated into glucose. What are the reasons for this to occur? And if we have to make a flow diagram to show this...how will the series of reaction take place.

Fumarase Deficiency

Fumarase deficiency is an extremely rare disease in humans. People with this disease can survive although they are significantly affected. a) Given the importance of fumarase to the citric acid cycle how is it possible for people with fumarase deficiency to produce adequate ATP for survival? b) what would be the overall


The following kinetic data was obtained using a substrate and an inhibitor. Find Km and Vmax for the substrate in mM and mM/min, then determine the type of inhibition and determine the Ki or Ki's. [S] mM [I] mM Rate mM/min 10 0 600 20 0 667 30 0 692 40 0 706 50 0 714 60 0 720 10000 0 750 10 30 273 20 30 400 30 30 4

Finding Vmax and Km from [S] and Vobs Data

With the following info for the activity of an enzyme in the absence and presence of compound A, what is the: Km of the enzyme, the Vmax of the enzyme, and the action of compound A ( an inhibitor, stimulator, modulator, etc) and please describe why. S (mM) Vobs control Vobs with cmpd A 0.1 0.68 0.91 0.2 1.25 1.67 0.5

Km and Vmax: Derivation from 2 Substrates and 2 Vobs

Can you help me derive the equations necessary to calculate Km and Vmax with a given observed velocity at two substrate concentrations. What is Vmax and Km if you know Substrate1 and Substrate2 and the matching Vobs1 and Vobs2? Thank you for all your help.

Equilibrium Concentration from Keq and Initial Concentration

Part 1: what is equilibrium concentrations and concentration ratios of glucose-6-phosphate/glucose-1-phosphate in the phosphoglucomutase reaction when the initial concentration of glucose-6-phosphate is (a) .01 M and (b) 10^-3 M. The Keq for the reaction below is 19. Glucose-1-phosphate ---> glucose-6-phosphate Part 2: wh


You want to make a 0.1M acetate buffer from 0.1M solutions of acetic acid and acetate. How many mL of acetic acid would you need per liter of solution (with the rest of the volume coming from the acetate solution) to generate a pH of 4.75? The pKa of acetic acid is 4.76

Pka Histidine Protein Active Site

The pKA of histidine in a protein active site where it is next to an aspartate or glutamate would be____________ the pKa of free histidine solution higher, lower, no different Is it higher??

Hydrolysis of Phosphocreatine

For the hydrolysis of phosphocreatine: Phosphocreatine + H2O==creatine + Pi the standard state deltaG is -42.8 kJ/mol at 37 degrees celsius. If in a given cell the concentration of creatine is 1.7mM, phosphate is 5.8mM, and phosphocreatine is 6.4mM, what is the deltaG for hydrolysis of phosphocreatine in the cell? Nearest 0.

Delta G

The equilibrium constant for the denaturation of a protein is determined to be 0.13 at 59.8 degrees Celsius. What is the standard state of delta G for the reaction, in kJ/mol to 0.01kJ/mol.

Phosphate System and Physiological pH

The phosphate system serves to buffer the intracellular fluid of cells at physiological pH because pK2 (7.20) lies near the normal pH range of 6.9-7.4. If the total cellular concentration of phosphate is 19mM and the pH is 6.9, what is the concentration of (H2PO4-) in mM?? Is this correct??? H2PO4-(aq) H+(aq) + HPO42-(aq)

Free energy and its affects

What affect does the presence of metal ions like Mg++ in the cell have on free energy of hydrolysis of ATP?? raise, lower, or no affect why??