Questions
1. If the enzyme-catalyzed reaction E + S ↔ ES ↔ E + P takes place...

1. If the enzyme-catalyzed reaction E + S ↔ ES ↔ E + P takes place near Vmax to the enzyme (E), what can be concluded about the relative concentrations of S and ES?

a) High [S], [ES] is low

b) High [S], [ES] are at their maximum

c) Low [S], [ES] is low

d) Low [S], [ES] is at its maximum

2. Which of the following statements about Michaelis-Menten kinetics is correct?

a) Km = the substrate concentration required for the reaction to reach Vmax

b) Km = dissociation constant of the enzyme-substrate complex

c) Km = is a measure of the substrate's affinity for the enzyme

d) Km = expression of reaction rate

3. What is the Km value if the substrate concentration is 25 mM and the initial reaction rate is half Vmax for an enzyme catalyzed reaction?

a) Km = 50 mM

b) Km = 12.5 mM

c) Km = 625 mM

d) Km = 25 mM

In: Chemistry

The choice of acid is important in the dehydration reaction. The following acids are not suitable...

The choice of acid is important in the dehydration reaction. The following acids are not suitable for dehydration of 2-butanol: acetic acid and hydrobromic. Explain why each of the acids would not be a good choice to affect the dehydration in good yield.

In: Chemistry

A simple enzyme reaction can be described by the equation E+SESE+P, where E is the enzyme,...

  1. A simple enzyme reaction can be described by the equation E+SESE+P, where E is the enzyme, S the substrate, P the produce, and ES the enzyme substrate complex.
  1. Write a corresponding equation describing the workings of a transport (T) that mediates the transport of a solute (S) down its concentration gradient.

  1. What does this equation tell you about the function of a transporter?

  1. Why would this equation be an inappropriate choice to represent the function of a channel?

In: Biology

1. Describe how attaching an enzyme to the cell membrane regulates the rate of a specific...

1. Describe how attaching an enzyme to the cell membrane regulates the rate of a specific reaction

2. Describe the type of reaction that is typically regulated by an allosteric enzyme based on DG for the reaction.

3. Differentiate between positive and negative feedback loops based on sequence of reactions resulting the formation of a final product, “F”

4. Differentiate between the [S] that gives half maximum velocity based on an allosteric enzyme without and with an allosteric activator

In: Biology

1. Describe the function of the following enzymes: glycogen phosphorylase, glycogen synthase, protein kinase a, adenylate...

1. Describe the function of the following enzymes: glycogen phosphorylase, glycogen synthase, protein kinase a, adenylate kinase, branching enzyme

2. a. Why do cell extracts require NAD+ to convert glucose to pyruvate? What intermediates accumulate when NAD+ is absent? Explain. b.Why does the rate at which glucose is converted to pyruvate decrease when citrate is added?

3. Define gluconeogenesis. What molecules are good substrates for gluconeogenesis? Biosynthetic and catabolic pathways are rarely identical. Is this true for gluconeogenesis vs. glycolysis? Explain.   

4. a. How does a D-glucose differ from B D-glucose? b.What is the difference between a 1-6 bond between two glucose molecules and a 1-4 bond? c.What is the difference between fructose and glucose? d.How does ribose differ from glucose? e.Carbohydrates (glucose, for example) are frequently phosphorylated upon entering a cell. Why?

5. Determine whether the following statements regarding free energy change are true or false. If false, change them to make the statement true.

Free energy change is a measure of the speed of the reaction.

Free energy change is a measure of the maximum amount of work available from the reaction.

Free energy change is a constant for a reaction under any conditions.

Free energy change is equal to zero at equilibrium.

The hydrolysis of ATP proceeds with a negative G.

In: Chemistry

The amino acid glutamic acid has the molecular formula C5H9NO4, and the amino acid isoleucine has...

The amino acid glutamic acid has the molecular formula C5H9NO4, and the amino acid isoleucine has the molecular formula C6H13NO2. Determine how many moles of isoleucine contain the same number of atoms as 1.96 mol of glutamic acid.

In: Chemistry

The amino acid glycine is often used as a component of buffers in biochemical experiments. The...

The amino acid glycine is often used as a component of buffers in biochemical experiments. The amino group of glycine has a pKa of 9.6, which can exist in the protonated form -NH3+ or the free base -NH2 as shown in this equilibrium:

        R-NH3+ ⇌ R-NH2 + H+

(a) Using glycine as a buffering agent requires specific pH ranges. Identify the buffer range for glycine’s amine group and describe how this molecule provides buffer capabilities as small amounts of HCl(aq) is added to the solution.

(b) In a 0.1 M solution of glycine at pH = 9, what fraction of glycine has its amino group in the -NH3+ form?

(c) When 90% of glycine is in its -NH3+ form, what is the numerical difference between the pH of the solution and the pKa of the amino group?

In: Biology

Introduction: Case Study: Surgical Robot Arms Race In the greater Seattle-Tacoma area, an arms race continues...

Introduction:
Case Study: Surgical Robot Arms Race

In the greater Seattle-Tacoma area, an arms race continues between hospitals to gather the most modern technology available to use on their patients – currently this arms race’s primary device of choice – robotic surgical systems. Why robotic surgical systems? These systems in theory allow surgeons to be more precise in performing complex surgical procedures on patients. With greater precision comes a greater chance of successfully healing the patient as well as reducing the patient’s possibility for complications and recovery time. In addition to these benefits, hospitals through the use of superior technology can serve more patients and potentially reap greater benefits from insurance companies and patients for these advanced medical services.
The price of this superior care though comes at a cost to the patient (increased charges) as well as purchase costs to the hospital. One of the most popular robotic systems is called da Vinci and is manufactured and sold by Intuitive Surgical (http://www.intuitivesurgical.com/). The da Vinci was FDA approved in July 2000 and can currently perform urologic, gynecologic, colorectal, head and neck, cardiothoracic, and other general surgery procedures. As important as the device is the surgeon that is trained in the use of the system. The more repetitions on the robotic system, the more skillful the surgeon becomes.
Depending on the options that a hospital chooses to purchase, the cost of a da Vinci system can range between 1 million and 3 million dollars with the associated sales taxes. As with all surgical instruments, there are also disposable items needed during a surgery associated with equipment – specifically the da Vinci which must also be purchased. These items range from $1,000 to $3,000. Finally, as with many pieces of sophisticated electronic technology, it must be maintained. These maintenance costs can be upwards to $200,000 a year. In addition to these specific costs, hospitals must continue to maintain the surgical suites that this equipment occupies as well as utilize all other supplies that would be used in any surgical setting.

The Deal:
A local hospital in the Puget Sound area faced a dilemma in the medical arms race. Surrounding hospitals were purchasing and utilizing the da Vinci robot system. Management began to worry about the erosion of patients that would seek out this modern technology over more traditional surgical procedures. To this end, a strategic decision was made to acquire the da Vinci robotic surgical system. The following data was presented to an analyst in the Finance Department for review:

Table 1:
Quite often, analysts are provided leasing information by the leasing company. Hospitals may choose to purchase equipment outright or acquire equipment using a lease. Leases are generally considered operating or capital leases under current accounting rules. Hospitals may purchase equipment outright if they have sufficient capital (money that can be used to purchase equipment of significant amount – usually greater than $5,000). Otherwise, they may decide that if the interest rate of payments being charged is lower than their internal cost of capital (debt financing, equity financing, etc.), they may utilize the lease directly from the equipment seller.
Lease Term:
36 Months
Lease Payment:
$68,742.10
Purchase Price:
$1,900,000.00
Page 2 of 8

Given the information provided in Table 1:
1. What is the annual rate of interest being charged to the hospital? The total interest paid over the entire term of the lease?
2. Given this rate of interest, give some reasons on why or why not the hospital should accept this lease contract. Is this a good deal for the lessee?
3. Why would a hospital care whether it was a capital lease or an operating lease? When would one be an advantage over the other?

In: Accounting

30.0 uM(microMolar) solution of enzyme catalyzed breakdown of 0.250M of substrate in 2 minutes. How many...

30.0 uM(microMolar) solution of enzyme catalyzed breakdown of 0.250M of substrate in 2 minutes. How many molecules of substrate were converted to product each second by one enzyme molecule?

In: Chemistry

1. Describe the link between understanding enzyme mechanism and drug design and development. 2. How does...

1. Describe the link between understanding enzyme mechanism and drug design and development.

2. How does regulation of 1 enzyme in a metabolic pathway modulate the flux through the entire pathway?

In: Chemistry