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Biological Chemistry

hydroylsis activity assay

I am conducting an activity assay to assess the Enzymatic Hydrolysis of 4-Nitrophenyl ?-D-Glucopyranoside by ?-D-Glucosidase. I am happy with the assay, however one of the components is bovine serum albumin ( 0.2% solution in phosphate buffer, to which my enzyme solution is added). I initially assumed that the BSA acted as so

Buffer Preparation - pH

Can you help me with the following problem? You and your lab partner are responsible for making the buffer 1 M Tris-HCl pH 7.4. After much time, the closest you can get to pH 7.4 is 6.4. Your partner is trying to convince you that 1 pH unit is close enough. What is (or should be) your response?

Calvin cycle and its role in ATP synthesis

Please help with the given questions: 1. How does the Calvin cycle make sugar from carbon dioxide? Where does the energy come from to drive this cycle? 2. How do respiration and/or photosynthesis affect homeostasis in a living organism?

Crystalline Proteins With Societal Impact/Use

I have to give a 30 minute speech in a couple of weeks about a specific protein. The protein needs to have a crystal structure and have some type of societal impact. I would like a protein that is involved in sports or bodybuilding because that is the subject outside of school that I am most interested in. My question is basical

Cellular Respiration and Photosynthesis

Photosynthesis uses light energy to convert carbon dioxide into glucose, a simple sugar, in two steps, the light dependent and light independent reactions. Oxygen is produced as a by product during photosynthesis. This reaction stores energy in the chemical bonds of glucose. Sugar and other carbohydrates are used as fuel sour

VIII-von Willebrand Factor Complex Inhibits Osteoclastogensis

I need a summary and an explanation for this article: Factor VIII-von Willebrand Factor Complex Inhibits Osteoclastogenesis and Control Cell Survival, Received for publication, June 5, 2009, and in revised form, August 18, 2009 published. Marc Baud'huin, Laurence Duplomb, Stephane Teletchea, Celine Charrier, Mike Maillasso

Relationship Between Tm and Base Pair Content

Based on the attached data collected from DNA isolation from two different bacterial cultures: 1. Complete the table by determining the percentage content of the corresponding complementary bases for each bacterial population. On what assumptions are your calculations made? 2. Describe the relationship between Tm and base

Lineweaver-Burk, Eadie-Hofstee, and Woolf Plots: Example Problem

Using the data in the attached file, prepare Lineweaver-Burk, Eadie-Hofstee, and Woolf plots. To determine the effect of errors in concentration, prepare Lineweaver-Burk and Eadie-Hofstee plots of the data where the concentration of the lowest 3 concentration of substrates are off by 10, 6, and 4% (the most error is associated w

Definitions and Urea Cycle

A) Define "transamination" and "oxidative deamination" b) What is the role of the urea cycle, and what are the effects on an individual of a deficiency in one of the required enzymes?

SDS-Page Electrophoreis to Identify the Molecular Weight

See the attached files. I recently completed a experiment on SDS-Page electrophoresis to identify the molecular weight of my unknown proteins (unknown a and unknown b). I recently received my photograph that I took and I am having a hard time reading it. First off I am having difficult interpreting my photo as I only know that

Cell Biology/Biochemistry questions

1. The stimulus for secretion of neurotransmitters into the synaptic cleft is an increase in A) sodium levels. B) calcium levels. C) neurotransmitter levels. D) chloride levels. E) potassium levels. 2. Multiple sclerosis is a result of A) the absence of myelin on nerve cells. B) having excess acetylcholine receptors.

Experiment on Enzyme inhibition

An experiment was performed to determine the effects of an inhibitor on the breakdown of glycogen by an enzyme. In an accompanying experiment, the inhibitor was added to the glycogen-enzyme suspension and reacted using the same experimental conditions. The data obtained from these experiments are in the table Glycogen (mM) 0

Biochemistry: Liver Mitochondria Oxygen Uptake Inhibition

1. A drug impairs oxyegen consumption on liver mitochondria at a buffer of 7.4pH, Mg, and adp. It inhibits O2 uptake if isocitrate, 2-ketoglutarate and malate were substrates, but it will NOT is succinate is a substrate. Where's the site of inhibiiton: ATP synthase, malate dehydrogenase, Complex I, II, or III 2. Wha

Define photosynthesis in plants

What is needed for photosynthesis and what is the wast product of photosynthesis? Also, given what you know about photosystems and how plants use visible light in photosynthesis.

Prepare 100 mL of 5mM Ascorbic Acid with 35mM Solution

Please help solve the following dilutions problems with step by step calculations. 1) Prepare 100 mL of 5mM ascorbic acid with 35mM ascorbic acid solution 2) Calculate the final concentration when the 5mM is diluted to 1:500 If you wanted to make 100 mL of a 5mM ascorbic acid solution and you have on hand a 35mM ascorbic

Absorbance and Concentration

A 5.0 mL aliquot of a stock tryptophan solution was diluted by adding 95 mL of water. The absorbance of that diluted solution was measured at 280 nm as 0.055 absorbance units. What is the concentration of the stock (original) solution? Hint: Make sure to calculate the dilution factor. (Molar extinction coefficient = 5579 cm-1 M-

Dilution Example Problems

1. If you wanted 10mL of a 1mM nitrophenol solution and you have on hand a 50mM nitrophenol solution, how would you make it? 2. If you wanted 100mL of a 0.1M acetic acid solution, how much 17.4M acetic acid and how much water do you need to add to make the 100mL of 0.1M acetic acid?

What is the Definition of Being Alive?

This is to be a philosophical discussion... What are the characteristics of life? There are some things, like planets, stars, viruses and prions that have many of the characteristics of life, but are not alive. ... How is it that these (or something you've researched) come close to being alive, but are not? Do you think that the

Km and Vmax Using Michaelis-Menten Kinetics

I've attached a table and my calculations to find Km and Vmax for an enzyme following Michaelis Menten Kinetics and well as identifying what kind of inhibitor I is. I think my proposed solution is too simple and I must be missing something. If so, what am I overlooking and how do I figure this out?

Silicon vs. Carbon Life Forms

In the movie, Lost in Space, spider-like creatures attacked members of the Robinson family as they explored an abandoned spaceship. Maureen (the mom) scans the creatures and reports that the spiders are silicon-based life-forms. (1) If silicon-based life exists, would it be able to consume carbon-based life, digest it, and u

Comparing and Contrasting Photosynthesis and Aerobic Cellular Respiration

Cellular Respiration and Photosynthesis co-exist as paired metabolic processes. Photosynthesis uses light energy to convert carbon dioxide into glucose, a simple sugar, in two steps, the light dependent and light independent reactions. Oxygen is produced as a by product during photosynthesis. This reaction stores energy in

Metabolic Pathways

Please help me with two of these questions. 9. Glucose is experimentally synthesized with C-14 at carbon 1, and used as a substrate for aerobic metabolism. Where is the label at the end of glycolysis? Draw the glycolysis product with the labeled carbon circled or highlighted. Now take that glycolysis product a little farther.

How can DCCD be used to study ATP synthase?

Conduction of protons by the F0 unit of ATP synthase is blocked by modification of a single side chain by dicyclohexylcarboiimide (DCCD). What are the most likely targets of action of this reagent? How might you use site-directed mutagenesis to determine whether this residue is essential for proton conduction?

What is the yield of ATP

What is the yield of ATP when each of the following substrates is completely oxidized to CO2 by a mammalian cell homogenate? Assume that glycolysis, the citric cycle and oxidative phosphorylation are fully active. a) Pyruvate b) NADH c) Fructose 1,6-biphosphate d) Glucose e) Dihydroxyacetone phosphate (Plea

ATP Production From Oxidization Of Ethanol

Ethanol is oxidized in the liver to form acetate, which is converted to acetyl-CoA. Determine how many molecules of ATP are produced from 1 mol of ethanol. Note that 2 mol of NADH are produced when ethanol is oxidized to form acetate.


Using a spectrophotometer set at 400 nm, an absorbance reading of 0.050 was obtained for a solution of p-nitrophenol at pH 6.5. The molar extinction coefficient of p-nitrophenol 21500 M-1cm-1 and the pka for p-nitrophenol is 7. What is the total concentration of p-nitrophenol in the experimental solution.