Tamil Nadu 12th Std Model Question Paper 2026 Microbiology

Tamil Nadu Board Model Question Paper

No. of Printed Pages : 7
8362
!8362Microbiology! £vÄ Gs
Register Number

PART - III
~sq°›¯À / MICROBIOLOGY
( uªÌ ©ØÖ® B[Q» ÁÈ / Tamil & English Version)

Põ» AÍÄ : 3.00 ©o ÷|µ® ] [ ö©õzu ©v¨ö£sPÒ : 70

Time Allowed : 3.00 Hours ] [ Maximum Marks : 70

AÔÄøµPÒ : (1) AøÚzx ÂÚõUPЮ \›¯õP £vÁõQ EÒÍuõ GߣuøÚ \›£õºzxU
öPõÒÍÄ®. Aa_¨£vÂÀ SøÓ°¸¨¤ß AøÓU PsPõo¨£õÍ›h®
EhÚi¯õPz öu›ÂUPÄ®.
(2) }»® AÀ»x P¸¨¦ ø©°øÚ ©mk÷© GÊxÁuØS®,
AiU÷PõikÁuØS® £¯ß£kzu ÷Ásk®. £h[PÒ ÁøµÁuØS
ö£ß]À £¯ß£kzuÄ®.
(3) ÷uøÁ¯õÚ Ch[PÎÀ £h[PÒ ÁøµP.
Instructions : (1) Check the question paper for fairness of printing. If there is any lack of fairness,
inform the Hall Supervisor immediately.
(2) Use Blue or Black ink to write and underline and pencil to draw diagrams.
(3) Draw diagrams wherever necessary.

£Sv & I / PART - I
SÔ¨¦ : (i) AøÚzx ÂÚõUPÐUS® Âøh¯ÎUPÄ®. 15x1=15

(ii) öPõkUP¨£mkÒÍ |õßS ©õØÖ ÂøhPÎÀ ªPÄ® Hئøh¯
Âøhø¯z ÷uº¢öukzxU SÔ±mkhß Âøh°øÚ²® ÷\ºzx
GÊuÄ®.
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.

8362 2

1. |õ-÷Úõ xPÒ-P-Îß AÍÄ __________.
(A) 100 nm AÀ-»x AvP® (B) 10 nm SøÓ-Áõ-P
(C) 10 nm AÀ-»x Av-P® (D) 100 nm AÀ-»x SøÓ-Áõ-P
Size of the Nano particles varies from __________.
(a) 100 nm or more (b) Less than 10 nm
(c) 10 nm or more (d) 100 nm or less

2. ¤ß-Á-¸-Á-Ú-ÁØ-ÔÀ GøÁ ©õ-v-›-°ß •¨-£-›-©õn £-hz-vøÚ ö£Ö-Á-vÀ, |©US
Eu-Ä-Qß-ÓÚ ?
(A) Tm-k- ~s-÷nõU-Q (B) TEM
(C) GÎ-¯ ~s-÷nõU-Q (D) SEM
Which among the following helps us in getting a 3-D picture of specimen ?
(a) Compound microscope (b) TEM
(c) Simple microscope (d) SEM

3. ¤ß-Á-¸® Põ-µ-o-P-ÎÀ Gx Ps ©¸¢øu £u¨-£-kz-x-Á-uØS £¯ß-£-k-Q-Óx ?
(A) ¥ÚõÀ (B) BÀ-P-íõÀ
(C) BÀ-i-øí-kPÒ (D) |õß-Q-øn¨¦ A®-÷©õ-Û¯ E¨-¦
Which of the following agents are used as a preservative in Ophthalmic Solution ?
(a) Phenol (b) Alcohol
(c) Aldehydes (d) Quaternary ammonium salts

4. H›-P-Î-¾® ©Ø-Ö® }a-\À -SÍ[-P-Î-¾® £õ-]-P-Îß Áͺa-]ø¯ ukU-P __________
£¯ß-£-kzu¨£-k-Q-Óx.
(A) £õº-©õÀ-i-øí-k (B) Põ¨-£º \À-÷£m
(C) BÀ-P-íõÀ (D) ]À-Áº ø|m-÷µm
__________ is used in lake and swimming pools to retard the growth of algae.
(a) Formaldehyde (b) Copper sulphate
(c) Alcohol (d) Silver nitrate

5. JÆ- ö Áõ¸ SÐU- ÷ Põì ‰»U- T - Ö - P - Ð ® BU- ê - \ - ÷ ÚØ- Ó - © - ø h¢x __________
ø£¸-ÂU Aª-» ‰»U-T-Ö-PÒ EØ-£z-v-¯õ-Qß-ÓÚ.
(A) 3 (B) 1 (C) 4 (D) 2
For every one molecule of sugar glucose which is oxidized __________ molecule of pyruvic
acid are produced.
(a) 3 (b) 1 (c) 4 (d) 2

3 8362

6. ~s-q-°-›-PÒ Á͵ HØÓ pH ©v¨¦ __________.
(A) 3.4 (B) 4.0 (C) 9.2 (D) 7.0
The micro-organisms grow best at pH value around :
(a) 3.4 (b) 4.0 (c) 9.2 (d) 7.0

7. •ußø© ÷uº-Ä- •-øÓUS Kº Gkz-xU-Põmk :
(A) BU-÷\õ-÷Úõ-Q-µõ-¤ (B) JΨ-£-h-Â-¯À
(C) öh¼-Q-µõ¤ (D) vøµ¨-£-h-Â-¯À
__________ is an example for primary screening.
(a) Auxanography (b) Photography
(c) Telegraphy (d) Cinematography

8. öÁ°-¼ß ÷|õ´ ¤ß-Á-¸® GÆ-ÁøP £õU-j-›-¯õ-ÁõÀ Es-hõU-P¨-£-k-Q-Óx ?
(A) ö»¨-÷hõì-ø£-µõ Cß-hº-÷µõ-Pßì
(B) \õÀ-÷©õ-öÚÀ-»õ øh¤
(C) ¨-›-÷¯õ Põ-»÷µ
(D) Göå-›-]-¯õ ÷Põ-ø»
Weil's disease is caused by which of the following bacteria ?
(a) Leptospira interrogans
(b) Salmonella typhi
(c) Vibrio cholerae
(d) Escherichia coli

9. ]¤-¼ì-êß ÷|õ´ Põ-µ-o __________.
(A) i›¨-÷£õ-Û-©õ £õ-¼-h® (B) ö|´-ë-›-¯õ ö©Ûß-øá-iì
(C) ìöh-ø£-÷»õ-PõU-Pì B›-¯ì (D) ìmöµ¨-÷hõ-PõU-Pì ø£÷¯õ-ãßì
__________ is the causative agent of Syphilis.
(a) Treponema pallidum (b) Neisseria meningitidis
(c) Staphylococcus aureus (d) Streptococcus pyogenes

10. ~s- ÷ nõU- Q - ° À ¼³- Á ß íõU ©»U- P - È øÁ EØ- Ö - ÷ |õUQ, Ps- h - Ô ¢u •uÀ
Jm-kso E°-›-²-hß öuõ-hº¦ öPõsh ÷|õ´ __________ BS®.
(A) ©÷»-›-¯õ (B) \õ-Põì ÷|õ´
(C) Aì-Põ-›-¯õ-]ì (D) â¯õº-i-¯õ-êì
This disease was first observed by Leeuwenhoek after he discovered parasitic organisms in
his stool under the microscope.
(a) Malaria (b) Chaga's disease
(c) Ascariasis (d) Giardiasis

8362 4

11. __________ &ß ö\¯À -ÂÍU-P® ›ÚõÀmì&¨-µõm {PÌÄ Gß-Ó-øÇU-P¨-£-k®.
(A) öẮ SÇÀ (B) Bºz-÷µõì-÷£õº
(C) ì÷£õ-µg-]-÷¯õì-÷£õº (D) QÍõ-ª-÷hõì-÷£õº
Demonstration of __________ is called as Reynolds-Braude phenomenon.
(a) Germ tube (b) Arthrospore
(c) Sporangiospore (d) Chlamydospore

12. ¥m-hõ ¦÷µõ¨-¤-÷¯õ»õU-÷hõß uk¨-§] __________ UPõP öPõ-kU-P¨-£-k-Q-Óx.
(A) ÷µ¥ì øÁµì (B) HIV
(C) öí¨-£-øhiì øÁµì (D) CßL¨-ÑöÁß-\õ øÁµì
Beta propiolactone vaccine is given for __________.
(a) Rabies virus (b) HIV
(c) Hepatitis virus (d) Influenza virus

13. F}º AÀ-»x Cµz-u® ©õØ-Óz-vß ÁÈ-¯õP Phz-u¨-£-k® øÁµì ÁøP Gx ?
(A) öí¨-£-øh-iì B øÁµì (B) öí¨-£-øh-iì A øÁµì
(C) ]U-Sß Sß-¯õ øÁµì (D) âPõ øÁµì
Which type of virus is transmitted by serum or blood transfusion ?
(a) Hepatitis B virus (b) Hepatitis A virus
(c) Chikungunya virus (d) Zika virus

14. y]U Põ´a-\-ø» Es-hõU-S-Á-x __________.
(A) Áõ-\-øÚz vµ-Â-¯® (B) y]
(C) ©P-µ¢u yÒ (D) ÷©Ø-Psh AøÚz-x®
Hay Fever is caused by __________.
(a) Perfumes (b) Dust
(c) Pollen grains (d) All of the above

15. i.Gß.H __________ BP¨ £i-ö¯-kU-P¨-£-k-Q-Óx.
(A) sBº.-Gß.-H (B) mBº.-Gß.-H
(C) huBº.-Gß.-H (D) tBº.-Gß.-H
DNA is transcribed into __________.
(a) sRNA (b) mRNA
(c) huRNA (d) tRNA

5 8362

£Sv & II / PART - II
SÔ¨¦ : GøÁ÷¯Ý® 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. ìöh® ö\À-P-Îß •U-Q-¯zxÁzøu ÁÇ[-P-Ä®.
Give the importance of Stem cells.

17. ¦Ñµ-\ßì ~s-÷nõU-Q-°-¯-¾US £¯ß-£-kz-u¨-£-k® \õ-¯[-P-øͨ £m-i-¯-¼-kP.
List out the dyes used for fluorescence microscopy.

18. Áøµ-¯Ö- - iì-Cß-ö£U-hßm
Define Disinfectants

19. En-Ä öPm-k¨-÷£õ-uÀ Gß-ÓõÀ GßÚ ?
What is food Spoilage ?

20. ö|õ-v-P-»ß Gß-ÓõÀ GßÚ ?
What is Fermentor (Bioreactor) ?

21. QÍõìm-›-i-¯z-vß öhm-hÛ E¸Á Aø©¨¦ £ØÔ GÊ-xP.
Write the morphology of Clostridium tetani.

22. ø©U-Põ-»â – Áøµ-¯-ÖU-P-Ä®.
Define Mycology.

23. EÖ¨-¦-©õØ-Ó® Gß-ÓõÀ GßÚ ?
What is Transplantation ?

24. ]øu-©õØ-Ó® Gß-ÓõÀ GßÚ ?
What is Catabolism ?

8362 6

£Sv & III / PART - III
SÔ¨¦ : GøÁ÷¯Ý® 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»Um-µõß ~s÷nõU-Q-°ß £¯ß-PÒ ¯õøÁ ?
What are the applications of electron microscope ?

26. ÷Áv- ° - ¯ À Põ- µ - o - P - Î ß Bß- i - ø ©U- ÷ µõ- ¤ - ¯ À ö\¯- ø » £õ- v U- S ® Põ- µ - o - P Ò
¯õøÁ ?
What are the factors influencing the antimicrobial activity of chemical agents ?

27. EnÄ £-u¨-£-kz-x-u-¼ß |ß-ø©-PÒ ©Ø-Ö® wø©-PÒ ¯õøÁ ?
What are the advantages and disadvantages of food preservation ?

28. ÷©®-£-kz-u¨-£mh ]Ö-]Ø-Ô-Ú[-P-Îß £s-¦-PÒ H÷u-Ý® ‰ß-ÔøÚ GÊ-xP.
Write any three attributes of improved strains.

29. æöPÀ-»õ ÷£›-Úz-vß |õßS •U-Q¯ ]Ö-]Ø-Ô-Ú[PøÍ £m-i-¯-¼-kP.
List out the four important species of the genus Shigella.

30. £-hº-uõ-©-øµz öuõØÖ £ØÔ ]Ö-S-Ô¨¦ Áøµ-P.
Write a short note on Ringworm infection.

31. â¯õº-i-¯õ-Âß m÷µõ-÷£õ-\õ´møh £h® Áøµ¢x ÂÁ-›U-P-Ä®.
With a neat diagram describe the trophozoite of Giardia.

32. Gø»-\õ £ØÔ ]Ö-S-Ô¨¦ Áøµ-P.
Write short notes on ELISA.

33. Bß-i-£-¯õ-iU-êß ö\¯À-•-øÓ-°ß ÁÈ-•-øÓ Áøµ-£-hzøu Áøµ-P.
Draw a flowchart of mode of action of antibiotics.

7 8362

£Sv & IV / PART - IV
SÔ¨¦ : AøÚz-x ÂÚõU-P-ÐUS® Âøh¯ÎUPÄ®. 5x5=25
Note : Answer all the questions.
34. (A) iøµ-Põº-£õU-ê-¼U Aª-» _ÇØ] £ØÔ ÂÍU-SP.
AÀ»x
(B) Qº¤--£õ-¯º ÷\õ-u-øÚø¯ ÂÍU-SP.
(a) Describe Tricarboxylic Acid Cycle.
OR
(b) Explain the Kirby-Bauer Test.
35. (A) JÎ ©Ø-Ö® G»Um-µõß ~s-÷nõU-Q-P-ÐU-Q-øh÷¯ EÒÍ ÷ÁÖ-£õ-k-PøÍ
GÊ-x-P.
AÀ»x
(B) ~s-q-°º-PÒ £u¨-£-kz-x® •øÓ-P-ÎÀ H÷u-Ý® I¢-vøÚ GÊ-xP.
(a) Write the differences between Light microscope and Electron microscope.
OR
(b) List any five methods of preservation of micro-organisms.
36. (A) ö©z-v-½ß }»® \õ¯ JkUP ÷\õ-uøÚ £ØÔ ÂÍU-SP.
AÀ»x
(B) ©Û-uøÚ öuõØ-Ö® 40 cm }Í® ÁÍ-¸® ö£›-¯ E¸-øͦÊ-Âß ÁõÌUøP
_ÇØ-]ø¯ ÂÁ-›U-P-Ä®.
(a) Explain about Methylene Blue dye Reduction Test (MBRT).
OR
(b) Describe the life-cycle of large roundworm which grows to a length upto 40 cm that
infects humans.
37. (A) £õU-j-›-]hÀ ©Ø-Ö® £õU-j-›÷¯õì-hõ-iU-PõÚ ÷ÁÖ-£õ-k-PøÍ GÊ-x-P.
AÀ»x
(B) ¨-›-÷¯õ Põ-»-µõ-Âß ÷|õ´z-÷uõØ-Ó® £ØÔ ÂÍU-SP.
(a) Write the differences between Bactericidal and Bacteriostatic.
OR
(b) Explain the pathogenesis of Vibrio cholerae.
38. (A) Eh-Úi ªøP Tº EnºÄ ÁøP&I I ÂÁ›.
AÀ»x
(B) ÁøP A öí¨-£-øh-iì øÁµì £ØÔ Â›-ÁõP GÊ-xP.
(a) Explain Immediate Hypersensitivity Type-I.
OR
(b) Explain in detail about Hepatitis A virus.
-oOo-