TN 12th Question Paper 2026 Biochemistry

FOR TN 12TH EXAM PREPARATION

TN 12th 2026
Question Paper ·
Biochemistry
EXAM YEAR TYPE SUBJECT

TN 12th 2026 Question Paper Biochemistry

Notes · Sample Papers · Previous Year Papers · Mock Tests

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No. of Printed Pages : 8
9063

!9063BioChemistry! £vÄ Gs
Register Number

PART - III
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÷Áv°¯À / BIO-CHEMISTRY
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Time Allowed : 3.00 Hours ] [ Maximum Marks : 70

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Instructions : (1) Check the question paper for fairness of printing. If there is any lack of fairness,

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(2) Use Blue or Black ink to write and underline and pencil to draw diagrams.

(3) Draw diagrams and write equations wherever necessary.

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Note : (i) Answer all the questions.

(ii) Choose the most appropriate answer from the given four alternatives and write

the option code and the corresponding answer.

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9063 2

1. QÍõz›ß §\¨£mh SÈPÒ __________ Eu ¦›QßÓÚ .

(A) E°µq ÂÊ[Su¼À
(B) Enº÷Áؤ ÁÈ E°µq EmPÁºu¼À
(C) Fk¸Äu¼À
(D) E°µq öÁÎ÷¯ØÓzvÀ
Clathrin coated pits assist in __________.

(a) phagocytosis

(b) receptor-mediated endocytosis

(c) diffusion

(d) exocytosis

2. EnøÁ ¤izxU öPõÒÍÄ®, QÈUPÄ® £¯ß£k® £ØPÒ __________.

(A) •ßPøhÁõ´¨ £ØPÒ (B) öÁmk® £ØPÒ
(C) ¤ßPøhÁõ´¨ £ØPÒ (D) ÷Põøµ¨ £ØPÒ
__________ teeth are responsible for holding and tearing food.

(a) Premolar (b) Incisors

(c) Molar (d) Canine

3. ÷Põ¼]ì÷hõQÛß GÝ® íõº÷©õøÚ _µ¨£x __________.

(A) •ß ]Ö Sh¼¾ÒÍ ö\ÀPÒ I

(B) Cøµ¨ø£ SÈPξÒÍ G ö\ÀPÒ
(C) •ß ]Ö Sh¼¾ÒÍ C ö\ÀPÒ
(D) •ß ]Ö Sh¼¾ÒÍ ö\ÀPÒ S

Cholecystokinin is a hormone secreted by the __________.

(a) I cells of duodenum

(b) G cells of gastric pits

(c) C cells of duodenum

(d) S cells of duodenum

For more Question Papers, Sample Papers, Notes & Syllabus visit Page 2 of 8

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4. Cß_¼ß __________ BÀ _µUP¨£kQÓx .

(A) Pøn¯® (B) PÀ½µÀ (C) øuµõ´k (D) ]Ö}µP®
Insulin is secreted by __________.

(a) Pancreas (b) Liver (c) Thyroid (d) Kidney

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(C) ¦÷µõ¼ß
__________ serves as a precursor for dopamine.
(D) øímµõUê¦÷µõ¼ß

(a) Tyrosine (b) Tryptophan

(c) Proline (d) Hydroxyproline

6. Cµzu öPõ»ìiµõ¼ß C¯À£õÚ AÍÄ :

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(A) 500 mg/dL (B) < 200 mg/dL (C) 400 mg/dL (D) > 200 mg/dL

Normal value of blood cholesterol is :
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(a) 500 mg/dL

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(b) < 200 mg/dL (c) 400 mg/dL (d) > 200 mg/dL

7. ©µ¦zuPÁÀ ö©õÈö£¯ºzu¼À
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_________.

(A) ø©m÷hõPõsi›¯õ (B) ø»÷\õ÷\õ®
(C) EmP¸ (D) ›÷£õ÷\õ®
The cytoplasmic cellular organelle involved in translation process is _________.

(a) Mitochondria (b) Lysosome

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(c) Nucleus (d) Ribosome

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Deficiency in homogentisate acid oxidase causes :

(a) Tyrosinemia (b) Phenylketonuria

(c) Galactosemia (d) Alkaptonuria

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9063 4

9. Cµzu EøÓuÀ Põµo IV Gߣx :

(A) Q¸zx©ì Põµo (B) ø£¤›÷Úõáß
(C) íR©ß Põµo (D) PõÀ]¯® A¯ÛPÒ
Blood clotting factor IV is :

(a) Christmas factor (b) Fibrinogen

(c) Hageman factor (d) Calcium ions

10. G¢u AønÄ ¦÷µõmhõß CøÓ¨¤¯õP ö\¯À£hõx ?
(A) ø\m÷hõS÷µõ® ›hU÷hì AønÄ III

(B) NADH iøímµá÷Úì AønÄ I

(C) ø\m÷hõS÷µõ® BUê÷hì AønÄ IV

(D) \U]÷Úm iøímµá÷Úì AønÄ II

Which complex does not pump protons ?

(a) Cytochrome reductase complex III

(b) NADH dehydrogenase complex I

(c) Cytochrome oxidase complex IV

(d) Succinate dehydrogenase complex II

11. G»Umµõß HØø£ __________ GÚ ö£¯›h •i²®.
(A) BU]á÷ÚØÓ® (B) Áͺ]øu ©õØÓ®
(C) JkUP® (D) Áͺ©õØÓ®
Gain of electrons can be termed as :

(a) Oxidation (b) Metabolism

(c) Reduction (d) Anabolism

12. ES AønÄ E¸ÁõuÀ J¸ :

(A) BØÓÀ EÔg_® ÂøÚ (B) «Ò ÂøÚ
(C) •Êø©¯õÚ ÂøÚ (D) «Íõ ÂøÚ
ES complex formation is :

(a) an energy consuming reaction (b) a reversible reaction

(c) a complete reaction (d) an irreversible reaction

For more Question Papers, Sample Papers, Notes & Syllabus visit Page 4 of 8

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13. ysh¨£mh ö£õ¸¢xuÀ ©õv›ø¯ E¸ÁõUQ¯Áº :

(A) ÷Põè÷»sm (B) iU\õß
(C) ø©UP¼ì ö©ßhß (D) ¤èåº

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Induced fit model was proposed by :

(a) Koshland
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Michaelis Menten (d) Fischer

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(A) hõUéõ´k (B) Bm÷hõáß (C) ÷í¨÷hß (D) TSST-1

Which one of the following is a super antigen ?

(a) Toxoid (b) Autogen (c) Hapten (d) TSST-1

15. IgM Bßi£õi°À EÒÍ Bßiöáß Cøn²® £SvPÎß GsoUøP :

(A) 9 (B) 7 (C) 10 (D) 8

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Number of antigen binding sites in IgM antibody are :

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SÔ¨¦ : H÷uÝ® BÖ ÂÚõUPÐUS Âøh¯ÎUPÄ®. ÂÚõ Gs 24 &US
Pmhõ¯©õP Âøh¯ÎUPÄ®. 6x2=12

Note : Answer any six questions. Question No. 24 is compulsory.

16. \ÆÄ GßÓõÀ GßÚ ?
What is a membrane ?

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How are mixed micelles formed ?

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Aª»[PÎß ö£¯ºPøÍz u¸P.
|õßS Aª÷Úõ

Mention any four amino acids whose carbon skeletons enter into TCA cycle.

19. öPõ»ìmµõ¼ß •UQ¯©õÚ ö£ÖvPÒ ¯õøÁ ?
What are the important derivatives of cholesterol ?

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9063 6

20. GM1 BÚx GÆÁõÖ GM2 BP ©õØÓ¨£kQÓx ?
How GM1 is converted into GM2 ?

21. ø©m÷hõPõsi›¯õÂß Aø©¨ø£ ÁøµP.
Draw the structure of mitochondria.

22. §mk \õ ©õv›°ß£i, Q꼀 ø©¯zvß ußø© ¯õx ?
What is the nature of active site according to lock and key theory ?

23. G¤÷hõ¨ Áøµ¯ÖUPÄ®.
Define epitope.

24. SÐU÷Põ{÷¯õöáÛ]ì GßÓõÀ GßÚ ?
What is Gluconeogenesis ?

£Sv & III / PART - III

SÔ¨¦ : H÷uÝ® BÖ ÂÚõUPÐUS Âøh¯ÎUPÄ®. ÂÚõ Gs 33 &US
Pmhõ¯©õP Âøh¯ÎUPÄ®. 6x3=18

Note : Answer any six questions. Question No. 33 is compulsory.

25. G»Umµõß Phzx \[Q¼°ß AønÄ £ØÔ GÊxP. -I

Write about complex-I of Electron Transport Chain.

26. GTT £ØÔ ]Ö SÔ¨¦ GÊxP.
Write short notes on GTT.

27. A®÷©õÛ¯õ |a\õuÀ GßÓõÀ GßÚ ? Auß AÔSÔPøÍ u¸P.
What is ammonia intoxication ? Give its symptoms.

28. Bzv÷µõìQÎ÷µõ]ì £ØÔ GÊxP.
Write about atherosclerosis.

29. Aª÷Úõ Aª»[PÒ EÔg\¨£kuø» £õvUS® H÷uÝ® ‰ßÖ PõµoPøÍ
GÊxP.
Write any three factors that affect absorption of amino acids.

For more Question Papers, Sample Papers, Notes & Syllabus visit Page 6 of 8

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30. DNA Cµmi¨£øhu¼ß ‰ßÖ öÁÆ÷ÁÖ ©õv›PÎß ö£¯ºPøÍ GÊxP.
Write the names of three different models of DNA replication.

31. ‰ßÖ øÁµì ÷|õ´PøÍ AÁØÔØPõÚ ]Qaø\ •øÓ²hß £mi¯¼kP.
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32. ÷P»U÷hõ]ß Áͺ]øu ©õØÓzøu u¸P.

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Give the metabolism of galactose.

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33. ö\À \ÆÂß vµÁz ußø©ø¯ £õvUS® PõµoPøÍ GÊxP.
Write the factors that influence the fluidity of a cell membrane.

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Answer all the questions. Draw the diagrams wherever necessary.

34.
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(A) ï÷©õS÷Íõ¤ß uõ[PÀ Pøµ\À Aø©¨¦ £ØÔ ÂÍUSP.
AÀ»x
(B) ø»ßÃÁº £ºU Áøµ£h® GÆÁõÖ ö£Ó¨£kQÓx Gߣøu ÂÍUSP.
(a) Explain about the haemoglobin buffer system.

OR

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35. ³›¯õ _ÇØ] ©ØÖ® Auß •UQ¯zxÁzøu ›ÁõP
l as
ÂÍUSP.

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(B) ï÷©õ¤¼¯õ ÷|õ°ß Põµn® ©ØÖ® AÔSÔPøÍ ÂÍUSP.
(a) Elaborate on Urea Cycle and its significance.

OR

(b) Explain the causes and symptoms of Haemophilia.

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9063 8

36. (A) öÁÆ÷ÁÖ ÁøP¯õÚ EhØPõ¨¦ ‰»[PøÍ J¸ AmhÁøn°À
÷ÁÖ£kzxP.
AÀ»x
(B) E¯º BØÓÀ £õì÷£m ¤øn¨¦PÒ £ØÔ ÂÍUSP.
(a) Differentiate different types of antibodies with a neat table.

OR

(b) Explain about high energy phosphate bonds.

37. (A) Cøµ¨ø£U ShÀ íõº÷©õßPÒ £ØÔ ÂÍUSP.
AÀ»x
(B) QøÍU÷PõöáÛ]øé £ØÔ ÂÍUSP.
(a) Explain about Gastrointestinal hormones.

OR

(b) Explain about Glycogenesis.

38. (A) Cµmi¨£øhuÀ ö\¯À•øÓ°À
DNA £õ¼©÷µì ö|õv°ß £[øP DNA

ÂÍUSP.
AÀ»x
(B) öPõ»ìiµõÀ E°ºöuõSzu÷»õk öuõhº¦øh¯ £À÷ÁÖ £i{ø»PøÍ
_¸UP©õP ÂÍUSP.
(a) Explain the role of DNA polymerase in DNA replication.

OR

(b) Briefly explain about the various steps involved in cholesterol biosynthesis.

- o 0 o -

For more Question Papers, Sample Papers, Notes & Syllabus visit Page 8 of 8