First Year Biochemistry OSPE 2011 By Mohsin Ahmad & Nadeem Sabir
Enumerate 2 methods
to assess pH?
Write down Handuson
Hassen Berg equation
pH meter, pH indicator, pH Paper
pH= pKa + log[salt]/[acid]
Enlist
4 agents by which Proteins can be precipitated?
1. salts of heavy metals
2. organic solvent
3. acids / alkaloid agents
4. Con. Salt Solutions
5. Strong Acids
What clinical
significance of Blood in Urine?
Mention one cause of each painful and hematuria?
Ans: It is indicative of Renal Damage due to Infection,
Inflamation or Trauma
Cause of Painful hematuria is stone in Renal systemand
painless is truma
Define oligo urea
and an urea?
volume of urine less than 600ml/day is called oligo urea
volume of urine less than 100ml/day is called an urea
normal value 1-1.5 liter
Perform modified
Millet's test on given solution
Perform Molish's
Test on given solution?
Name the general
tests for detection of Proteins and enlist important plasma proteins?
Answer: Biuritte test
Albumin, Globulin Prothrombin fimbrinogen
Name the chemical
reactions by which derived carbohydrates are obtained? Give one example of each
Answer: oxidation products (Glucose-> Gluconic acid)
Reduction Product (Robose-> Ribitol)
Amino Sugars (Glucose-> Glucosamine)
Deoxy Sugars (Deoxy-ribose)
What is principle of
denaturation of Protein?
When a Protein is heated in an acid medium it become
denatured as the highly acidic/ Basic and other Physical and Chemical agents
can breakdown the force responsible to maintain quaternaary tertiary &
seecondary structures effecting only non-covlaent linkages while covalent
linkages remain intact
Define rancidity of
fats and give its types?
When fats are exposed to air, rise temperature, partial
hydrolysis and oxidation of fat occurs which imparts foul smell called
Rancidity
Types: oxidative hydrolytic
Perform iodine test
on given solution and heat effect?
Perform heat
coagulation Test on given solution?
Define standard and
normal solution.
standard solution is thah whose concentration is known.
Normal solution is that which contain number of gram equalent of solute
dissolved in solvent with final volume of 1 liter of solution
How NaH2PO4 is required
to prepare 0.5 molar phosphate solution (mol weight=138)
Answer:To prepare 0.5 molar solution of compound, dissolved
138*0.5=69 grm NaH2PO4 in H2O to make 1000ml of solution
Why glucose,
fructose, mannose give sane type of Osazone crystals?
Answer: Reaction takes place at C1 & C2, as all these
sugars differ in structure only at C1 & C2. So after reacting with
phenlyhydrazine, they acquire the same structure , so similar type of crystals
are formed
What is mannitol
& clinical importance?
Answer: It is reduction reaction of mannose
Clinical importance: reduces cerebral edema.
Convert 120 mg/dl of
glucose into mili moles? (mol weight=180)
Answer: mmol/L = (mg/100ml) *10 /mol weight
6.7mmol/liter
Name four coloured
reactions of protein?
Answer: 1 xanthoproetic
2 million's test
3 Biurette test
Lead acetate
ninhydrin test
what is normal value
of cholesterol level? Two function of cholesterol?
Answer: 150-200 mg/dl
Precursor of steroid hormones, component of cell membrane
precursor of vitamin D3 , Bile salts
Perform Hopkincole's
Test
Perform Ninhydrin
Test
Name the test to
detect presence of cholesterol in body and used in lab?
Answer: Liberman Burchard test
salkowiski test
How will you prepare
1M NaOH solution?
Answer: Take 40g of NaOH dissolve it in H2O to make 1000ml
of solution
Name the bile
pigment responsible for normal urine colour?
Urobillin (urochrome)
Name the bile
pigment present in urine along with their respective sources?
Answer: Urobillin and urobillinogen
Uroerthyrin
Source Haem degradation products
How bilirubin is
made H2O soluble in body?
Answer: It is made water soluble by its conjugation with
glucuronic acid
Colour of bilirubin
Answer: yellow colour
Which keto acid is
formed by trans emination of aspartate catalyzed by AST
Answer: oxaloactate
Name any 2
conditions in which elevated AST activity may be observed in plasma
Answer: 1) Myocardial infarction
2) Alcohlic Hepatitis
3) dermato myopathies
what is renal
glycourea and Renal Threshold?
Answer: In renal glycouria glucose is excreted in urine due
to lowering of Renal threshold. The blood glucose levels are in normal limits
Renal threshold is
max blood level of any substance, after which it starts appearing in urine.
It is 180mg/dl
Normal range of
serum calcium?
Answer: Normal Range = 85.-10.5 mg/dl
In which form Ca+2
is present in plasma?
Answer: 1. In ionized calcium
which
is active form 2. Protein bound mainly with albumin and complexed citrates
Phosphate and bicarbonates
Which amino acid is
mainly deaminated in liver
Answer: Glutamate ( amino acid)
Triacylglycerol
molecule contained in chylomicrons and VLDL particles are hydrolyzed by which
enzyme?
Answer: Lipo-protien Lipase Enzyme
Where this Enzyme is
Located/
Answer: Low density lipo-protein LDL are located inthe
endothelium of capillaries of adipose tissue heart and muscle but not in liver
Perform xanthoprotic
on the givenn solution?
Perform Benedict's test on the given sample of solution
Which test is
specific to detect casein in milk/ and why?
Answer: neumann's test. because it detects phosphate group
of casein.
What are
Lipoproteins and how they are classified?
Answer: Proteins in the form of apoprotein and lipids like
phospholipids and cholestrol and triglycerides or neutral lipids combine to
form lipoproteins. they are classified into HDL, LDL IDL, VLDL
What are the end
product of lactose hydrolysis by Enzymes? Also name the enzyme?
Answer: Glucose and Glactose. Lactose
Name one test to detect
the presence of uric acid in urine/ Uric acid is product of what compound's
metabolism?
Answer: Benedict's uric acid test , Murexide Test ,
schiff's Test
Uric acid is the end product of purine basis Adenine,
Guanine
Perform Gmellin's
test on the given sample of urine and note the inference?
Perform test for
chloride on the given sample and note inference?
Normal value of
serum cholestrol level? What are 3 conditions in which serum cholesterol level
in Body is decreased?
Answer: Normal range: 150-200mg/dl
1. hyperthyroidism
2. severe liver damage
3. mal nutrition
4. Chronic Anemia
What is iso-electric
pH of protein? Give its Clinical Application?
Answer: pH at which a protein molecule possesses no net
charge is called iso electric. it is denoted as pI.
At isolated pH the Proteins do not move in an electric field
shifting the pH below or above iso-electric pH is used for separation of
proteins by electrophoresis.
Convert 120mg/dl of
glucose into mmoles/liter
Enumerate 4
disadvantages of pH.
1. expensive
2. more time required
3. large volume required
4. technical expert to handle
Number of carbon
atoms in cholesterol molecule and at which position OH is present?
Name Cholesterol
Breakdown products?
What is glycosuria?
Define TmG
Presence of glucose in urine is known as glycosuria. TmG=
threshold maximum of glucose
Name two standard
amino acids containing sulphur?
Cysteine & Methionine
Name four organic constituents present in urine?
Urea uric acid ammonia creatine ketone bodies
Name three functions
of cholesterol
Maintain fluidity of cell membrane
Acts as precursor of vitamin D
Precursor of steroid hormones
How many grams of
NaCl are present in 0.2 mole of 200 ml solution of NaCl. Mol weight= 58.5
