Roll number

M.B.B.S First Professional

Examination, 2 62023
Biochemistry (General Biochemistry & Metabolism)

Paper-1
Time: 3 hours Maximum Marks: 100
Minimum Marks: 50

Note: Attempt all questions

Instruction; the candidates are required to answer only in serial order if there are many parts of a question answer them in
continuation.

PART-A
Give examples and
Q1. How are enzymes regulated in our system? Explain in detail the process of induction and repression.
20 marks
support your answers with illustrations.

Q2. (a) Write a short note on 10X2=20 marks

quantitative defects of hemoglobin.

(b) Write down the difference between glycoprotein and proteoglycans.

Q3. Multiple choice questions: IX10=10 marks

Which statement represents the characteristics of glucose?

(a) It is an aldose
(b) It is a C4 epimer of mannose
(c) It is present as L-isomer in the human system
(d) It cannot form furan structure
2. Which carbohydrate should be negative for Benedict's test

(b) Sucrose
(c) None of the above
(d) Both the above
3. Fetal lung maturity can be gauged by determining the?
(a) DPPC/Sphingomyelin ratio
(b) Phosphatidyl serine/sphingomyelin ratio
(c) Sphingomyelin/ DPPC ratio
(d) Sphingomyelin/phosphatidyl serinc ratio
4. Which lipoprotein is associated with the transport of dietary triglycerides?
(a) VLDL

Apo Al is the activator of which enzyme?

(a) Lipoprotein Lipase
(b) Pancreatic Lipase
(c) Lecithin Cholesterol acyl transferase
n(dh) Fatty acyl synthetase
Which one of the compounds is not involved in the de novo synthesis of the purine ring?
(a) Aspartate
(b) Glutamate

(c) Glycine
Ad) Carbon dioxide
Which stands true for the process of facilitated diffusion?
• (a) Requires specific carrier protein
(b) Requires hydrolysis of ATP
(e) Transport is concentration dependent
(d) Requires co-transport down the gradient
8. Insulin promotes glucose uptake by adipocytes and muscle cells by translocation of which glucose transporter?
(a) GLUT-1
(b) GLUT-2
GLUT-3
d) GLUT-4
9. Which one best characterizes the I-cell disease?

(a), Lysosomal enzymes become elevated in plasma

(b) Lysosomal enzymes are not properly targeted
(c) Both the above
(d) None of the above
 10.
Lipid synthesis and the process of detoxification mainly take place in which organelle?
(a) Mitochondria
(b) Lysosomes
(©) Ribosomes associated with the endoplasmic reticulum
() Smooth endoplasmic reticulum

PART 2
20 marks
Q1. Elaborate metabolic adaptations during the prolonged state of fasting.

Q2. (a) What is the significance of the pentose phosphate pathway? How NADPH is involved in preventing hemolysis?

(b) A full-term infant showed metabolic acidosis in the neonatal period. The child failed to gain weight and had small muscle
mass; biochemical analysis showed elevated pyruvate, lactate, and alanine. Supplementation with thiamine did not correct
the condition. What could be the possible diagnosis of this patient? 10X2=20 marks

Q3. Multiple choice questions 1X10=20 marks:

1. Which one component is expected to be elevated in plasma during the well-fed state of absorption?
• (a) Chylomicrons
(b) High-density lipoproteins
(c) Ketone bodies
(d) Apo Al
2. Urea cycle takes place in which cellular component?
(2) Mitochondria and cytosol
(b) Mitochondria and endoplasmic reticulum
(c) Cytosol and endoplasmic reticulum
(d) Mitochondria only
3. Which amino acids are metabolized primarily in the muscles rather than in the liver?
(a) Tyrosine, tryptophan and phenylalanine
(b) Valine, leucine and isoleucine
(c) Glycine, proline and serine
(d) Alaninc, Pyruvate, lactate

1.722
4. Melanin a pigment synthesized in the melanocytes are the metabolic product of?
(a) Tryptophan
• (b) Tyrosine
(c) Threonine
(d) Thiamine
Which group represents ketone bodies?
(a) Acetone, acetyl-CoA, and acetoacetate
(b) Acetone, acetoacetate, and B-hydroxybutyrate
(c) Acetone, Acetoacetate, and free fatty acids
(d) Acetone, lactate, and pyruvate
6. Which statement is correct for type I diabetes mellitus?
(a) Usually presented with obesity
(b) Genetic predisposition iS rare
(c) Frequency of ketosis is very strong
(d) Age of onset is either childhood or puberty
Body mass index ≥ 30 is classified.as?
(a) Normal
(b) Overweight
_ (c) Obese
My Morbidly obese
"Which of the following appears to be the rich source of trans fatty acids?
(a) Fish
(b) meat
O(c) Commercial baked and fried foods
(d) Eggs
9. Which statement best describes albinism?
(a) Characterized by defect in the tyrosine metabolism
(b) Multiple modes of inheritance
(c) Presented with increased risk of skin cancers
(d) All the above
10. The Soret band used to detect porphyrins spectrophotometrically is located at?
(a) 200 nm

(c) 600 nm
(d) 800 nm
 Set-2 3.4- Which indicates an abnormal renal function?
a) Blood urea 30 mg/dl b) GER + 125 ml/min
RollNO........................ MBBS--106 C) Serum creatinine 8 mg/dl.df Urine pH = 6.8
3.5- Urea clearance is lowered in:
M.B.B.S. - Fist Professional (Phase-l) a) Acute nephritis b) Chronic liver failure.
Chronic cardiac failure d) Benign hypertension
EXAMINATION - 16: b.-Maid 2023) 3.6-
Serum enzymes helpful in the diagnosis of myocardial
BIOCHEMISTRY infarction are the following except:
Paper - Second a) CK-MB
b) Troponin
Time: Threehours] [Maximum Marks •100 cyGlucose-6-phosphate dehydrogenase

Note: Attempt all questions (Part-A & Part-B Separately). Draw diagrams wherever necessary. Figures in 3.7- Serum acid phosphatase (ACP) level is increased in:
parenthesis indicate marks allotted to a question. a) Rickets. by Hepatoma
c) Prostatic Carcinoma d) Excess phosphate intake
PART- A 3.8- Immunoglobin classes are differentiated from each other on the basis of their:

a) Electrophoretic mobility
0.1.
Name the Fat-soluble vitamins. Describe the Chemistry, Biochemical functions, normal requirement, b) Molecular weight
sources, and Deficiency manifestations of vitamin D. (20) af By their light chains
d) By their heavy chains
Q.2. Give brief account of the following: (10 Each) 3.9- Which Immunoglobulin exist as a Dimmer?
a) Factors affecting the Iron absorption in the body.
b) A one year old male baby had growth retardation, reduced physical activity, muscle wasting 3.10- The structure of Immunoglobin Hinge region is exist in
(emaciation), loose fold of skin wrapped over bones. The mother of the child, now in third month which segment?
of gestation, informed the physician that she had been giving the child rice gruel, along with- a) VL b) VH c) CL d) CH
breast milk. The laboratory report of the child are given hereunder:

Parameter Subject Reference range

7 g/dl 13-15 g/dl PART- B
Serum proteins (total) 6 g/dl 6-8 g/dl
Serum albumin 3 g/dl 3-4.5 g/dl Q.1.Describe the various steps of protein biosynthesis
Serum potassium. 3.5 mEq/I 3.5-5 mEq/I (translation). (20)

What is the probable diagnosis? Discuss the causes and biochemical basis of the disease, its clinical
Q.2.Give brief account of the following: (10 each)
correlation and management.
(a)- Principle of DNA Fingerprinting and its application •
(b)- What is meant by detoxification? Give an account of the phase-II mechanisms of detoxification
0.3. Each of the questions below is followed by few suggested answers, select the one best response
(1x10=10)
among them: 0.3. Each of the questions below is followed by few suggested answers, select the one best response
3.1- Which of the following is not an emergency investigation? among them: (1x10=10)
© a) Potassium br Fasting glucose 3.1- All are involved in synthesis of DNA, except:
c) Creatinine d) Calcium a) DNA polymerase b) Topoisomerase.
3.2- All affect glucose tolerance test, except: c) Reverse transcriptase d) Deoxyribonuclease
a Liver diseases b) Acute infections 3.2- Which is an inhibitor of transcription in eucaryotes?
cy Vitamin B12 deficiency d) Hyperthyroidism b) Chloramphenicol
c) Alpha amanitin d) Streptomycin
function, except:
PTO
b) Cholesterol
a) Bilirubin.
d) Creatinine
Contd. Page-2
3.3-Which enzyme is used for preparing a recombinant
DNA molecule?
a) Restriction endonuclease b) RNA polymerase.
c) DNA polymerase d) Topoisomerase
3.4- Mechanism invoived in activation of proto-oncogene
to oncogene:
a) Insertional mutagenesis.
b) chromosomal transiocation
c) gene amplification
d) all of above
3.5- P53 gene is:

a) A protooncogene b) An oncogene
, c A tumor suppressor gene d) None of the above
3.6- Tumor markers for ovarian cancers are :

a) beta HCG b) AFP

el CA-125 d) CEA
3.7. The oxidation reactions of detoxification are catalyzed
by:
a) cytochrome- c b) cytochrome oxidase
c} cytochrome P450 d) cytochrome- a
3.8- Electrolyte analysis is carried out by the :

a) Colorimetry b). fluorimetry

c) flame photometry d) spectrophotometry
3.9- pH meter is based on the principle of
a) rate of movement b) adsorption
c) Charge ad} Electromotive force
3.10- Mobility of particles during electrophoresis is based on all the following factors, except:
a) Current voltage and ampere.
b) Quality of supporting medium •
el pH of buffer medium
d) Solubility of particular protein
 Roll No.
157
Name. Saromsh

MBBS . 1st Professional (Phase-I)

First Terminal Examination-sept - 2022

BIOCHEMISTRY
MM:- 100
Time: Three hours

NOTE: - Attempt all questions. Draw diagram wherever is necessary.

Figures in parenthesis indicate marks allotted to a question.

Q.1 What are Carbohydrates? Classify them with suitable examples. Add note
(20.)
on the functions of carbohydrates.

Q.2
(10)
(a) Briefly describe the structure and function of phospholipids.
be defined in
( Discuss the various levels of structural organization that may
(10)
protein structure, what are the forces which stabilise them?

of each.
0.3 Enumerate the major classes of Enzymes, giving an example
Discuss the various factors affecting the velocity of an
enzyme reaction. (20)

Q.4
(a Briefly describe the chemistry, Biochemical functions, Dietary sources,
Recommended Dietary Allowances (RDA) and deficiency manifestation of
(10)
vitamin B6.

various thyroid
(b) Enumerate the function of thyroid gland and classify the (10)
function tests to assess its functioning.

Reduc
 land Terminal
Uttar Pradesh University of Medical Science
Department of Biochemistry
Time: 02:40 Hr M.M. 80

ATTEMPT ALL QUESTIONS

Section -A

Q1: Write in brief about the fate of Pyruvic acid in hepatocytes. Describe the amphibolic
nature of citric acid cycle. Enumerate bioenergetics of this cycle. (10)

Q2: Discuss the synthesis of purine by De Novo synthesis and its regulation (10)

03: Describe sources, biochemical functions, requirements and deficiency manifestations

of Vitamin A. (10)

to the
Q4: A 45-year-old man, a known case of psoriasis (skin disease) presented
orthopaedics OPD with complaints of severe pain in the big toe from two days. He had two
similar episodes before lasting for 4-5 days and treated with analgesics. On general
examination, no abnormality was. X-ray of the right foot showed the presence of
tophaceous deposits around the metatarsophalangeal joint. Blood examination showed a
high uric acid level 9.8mg/dL (2x5 =10)

1. What is the most probable diagnosis.

2. Write the normal reference range of uric acid.
3. Draw a flow chart of the formation of uric acid from catabolism of purine.
4. Write the mechanism of action of drug used for it.
5. What precaution to be taken for this disease?

Section -B

01: Enumerate the major steps of synthesis of cholesterol. Name the rate limiting step.

Describe the role of cholesterol in atherosclerosis. (10)

Q2: explain the term transamination. Give one suitable example. What is the metabolic
importance of it. What is the clinical application of transaminase
estimation. (10)

03: Write short notes on:

(2x5=10)
(a) Tumour markers

(b) Why ketonuria occurs in both prolonged starvation and uncontrolled diabetes?
Give brief explanations

04: Write in brief about: (2x5=10)

(a) Xenobiotics

(b) factors affecting enzymes