Get premium membership and access revision papers, questions with answers as well as video lessons.

Got a question or eager to learn? Discover limitless learning on WhatsApp now - Start Now!

Integrated Laboratory Techniques Ii Question Paper

Integrated Laboratory Techniques Ii

Course:Bachelor Of Science In Biochemistry

Institution: Egerton University question papers

Exam Year:

UNIVERSITY EXAMINATIONS

THIRD YEAR EXAMINATION FOR THE DEGREE OF BACHELOR OF SCIENCE

END SEMESTER 2005/2006

BIOC 303: INTEGRATED LABORATORY TECHNIQUES 11

TIME:2 HRS

Instructions: Answer any five questions (20marks)

1.a) Define the term sedimentation coefficient on what factors does it depend?

b) An ultracentrifuge is operated at a speed of 60,000 rev min-1.

Calculate:

i) The centrifugal field at a point 6.0 cm from the centre of rotation.

ii) The relative centrifugal field (RCF).(14 marks)

2.a) Give the generalized equation for the movement of charged particles in an electric field and in an ionic medium.Define each of the terms in the equation.

b) Many different media have been developed for use as electrophoretic supports,including strips of cellulose and gels of agorose,polyacrylamide,or starch.Comments on the general advantages and disadvantages of each of these media.

c) Why use a gel? (in electrophoretic separations).(14 marks)

3.a) What is the function of the EDTA added to enzyme assay mixtures?

b) During the initial stage of an NAD+ linked dehydrogenase assay,the DA340 was 0.12 per min.The total vol of the reacting mixture was 2.5 ml.The protein conc of the enzyme preparation was found to be 1.25 mg/ml.What was the specific activity of the enzyme in international units?

Given: molar absorption coefficient of NADH is NADH at 340nM is 6.2 nM-1-1cm

4 a) Why is spectrofluorometry potentially more sensitive than spectrophotometry in enzyme/metabolite assay.

b) The reduced form of Nicotinamide adinine dinucleaotide (NADH) is an important and highly fluorescent coenzyme.It has an absorption maximum of 340nm and an emission maximum at 465nm.Standard solutions of NADH gave the following fluorescence intensities:

Conc.NADH (µmol/L)0.200------- 0.400------ 0.600----- 0.800 Relative Intensity 4.52----- 9.01----- 13.71------------- 17.91

i) Construct a calibration curve for NADH and determine the slope.

ii) An unknown exhibits a relative fluo rescence of 12.16.

Calculate the concentration of NADH.

5.Study the following reaction below the answer the question

C6H1206+H20+02-----E---C6H12O7+H202

E=Glucose oxidase

Suggest a method which may be used to glucose oxidase activity.Give reasons for your choice.

6.The following reaction is catalyzed by cholinesterase enzyme:

1CH3.2C02 3CH2 4CH2 N+5-7 (CH3)3(a cetyl choline)-----1CH3.2C02H(acetic acid)+ H0 C3H2 C4H2 N+5-7(choline) (CH3)3

a) Can radio chemical method be used in cholinesterase assay?

b) If yes,explain,giving the major steps required in its assay.If not, explain why not and give an alternative suitable method for cholinesterase assay.(14 marks)

Integrated Laboratory Techniques Ii Question Paper

More Question Papers

Popular Exams