Biochemistry Answers

yeast cells can catabolise glucose under both aerobic conditions (respiration) and anaerobic conditions (fermentation/glycolysis). In this experiment, we will study both processes using a culture of Saccharomyces cerevisiae which has been aerobically adapted. By relating the amount of ethanol produced to the amount of glucose consumed over the same period of time, we will attempt to determine which process is the most efficient provider of energy to the yeast cells. This assumes of course that the energy needs of the cells are similar under the two sets of conditions. 

how can we determine which process is more efficient by calculating Moles ethanol produced per mole glucose catabolized ??

Meningitis is a disease that is characterized by swelling of the meninges that puts pressure on the brain. Which is least likely to be a symptom of this disease?

Under which of the following conditions is the R form of Hb favored?

a.At low O2 partial pressures, as in the lungs.

b.At high O2 partial pressures, as in muscles.

c.At low O2 partial pressures, as in muscles.

d.At high O2 partial pressures, as in the lungs.

e.The R form of Hb does not depend on the presence of O2

Identify and describe two ways that you can reduce the effectiveness of an enzyme

Almost no metabolic reaction is able to occur without the help of an enzyme. Explain how the structure of an allosteric enzyme and substrate function to control a metabolic pathway. Include a specific example in your answer. 

Suppose you are working in a lab to optimize enzyme activity and you observe that the enzyme activity decrease with increase in time. What could be the possible reason/s?

what is the value of glycine pKa of nh3 group

16. How do activators and inhibitors affects enzymes activity?

11. Indicate which type of bonds are involved in the following

a. Formation of the primary structure of a protein

b. Stabilization of the alpha helix and beta pleated sheet structures of proteins

12.Identify the biomolecular composition of the following cells

a.Endoplasmic reticulum

b.Mitochondria

c.Cytoskeleton

d. Nucleus

13 Under aerobic catabolism of glucose ,in which compartment of the eukaryotic cell does the following reaction occurs?

a conversion of pyruvate to acetyl CoA

b.conversion of succinyl -CoA to succinate

c.conversion ofNADH to ATP.

d.conversion of phosphologlycerate to phosphoenolpyruvate.

14. Briefly outline how ATP is generated from glucose in the absence of oxygen. What is the importance of this pathway?

15. Briefly explain the process by which excess dietary carbohydrates and lipids are stored in the human body

6.Name two key enzymes involved in substrate level phosphorylation reactions of glycolysis

7.Briefly explain how acetyl - CoA used for fatty acid biosynthesis is transported from the mitochondria to the cytosol and indicate the state (fed or fasted ) under which this can occur.

8. Briefly explain how enzymes decrease the activation energy of biochemical reactions

9.write the mechaelis -Menten equation for enzymes catalysis and define the parameters.

10 what are the differences between competitive, non competitive and uncompetitive inhibitions?