Class 12 Medical Diagnostics 2020 Solved Paper

Table of Contents

Class 12 Medical Diagnostics 2020 Solved Paper

SECTION A

(Employability Skills) (10 Marks)

Answer any 4 questions out of the given 6 questions of 1 mark each. 1×4=4

1. ____________ is a form of communication that allows students to put their feelings and ideas on paper, to organize their knowledge and beliefs into convincing arguments, and to convey meaning through well-constructed text. 1

(A) Writing

(B) Speaking

2. ____________ is located below the Title bar and contains different menu options. 1

(A) Title bar

(B) Menu bar

3. What does S stand for in SMART goal? 1

(A) Specific

(B) Super

4. ____________ oversee green activities in their organization. 1

(A) Chief Sustainability Officers

(B) Chief Super officers

5. ____________ is the process of making yourself look neat, tidy, and clean. 1

(A) Washing

(B) Grooming

6. The process of working together in a group is ____________ . 1

(A) Teamwork

(B) Group work

Answer any 3 questions out of given 5 questions of 2 marks each. 2×3=6

7. Enumerate four types of phrases. 2

Ans: Noun, verb, adjective, and adverb.

8. How can the background style be changed in OpenOffice? 2

Ans: The steps to change the slide background in OpenOffice Impress are:

1. Select Page option from the Format menu.

2. The Page Setup dialog box appears.

3. Click the Background tab.

3. Click the Fill drop-down menu arrow and choose the desired fill effect.

9. How can you analyze problems in the decision-making process ? 2

Ans: In running an enterprise, an entrepreneur has to make several decisions. Therefore, the person must be capable of making suitable and timely decisions. In the present world, things move very fast. If an entrepreneur does not have the ability to make suitable and timely decisions, the person may miss out on an opportunity and incur losses.

10. Enumerate four jobs in water conservation. 2

Ans: Water quality testing, water conservation, water management, rainwater harvesting.

11. List down two benefits of Networking. 2

Ans: Networking helps improve listening skills and prompts you to ask thoughtful questions.

SECTION B

(Subject Skills) (50 Marks)

Answer any 10 questions out of the given 12 questions of 1 mark each. 1×10=10

12. Write down the full form of ESR. 1

Ans: Erythrocyte Sedimentation Rate

13. Name the chemical which prevents clotting of blood when mixed with it. 1

Ans: Anticoagulants

14. Which method is used for hemoglobin estimation? 1

Ans: Colorimetric Method

15. What do you mean by MCV ? 1

Ans: Mean Corpuscular Volume.

16. What are the main antigens of the Lewis system ? 1

Ans: Le a and Le b.

17. An ____________ is any substance, either protein or non-protein, but when introduced into an animal, causes the production of another specific substance called antibody. 1

(A) antigen

(B) immunoglobulin

18. _________ are temperature-controlled chambers which are well insulated. 1

(A) Hot air ovens

(B) Incubators

19. ____________ is the formation of visible insoluble complex when soluble antibody reacts with soluble antigen. 1

(A) Precipitation

(B) Agglutination

20. ____________ is a small bottlebrush-like device with one end having fine bristles made up of nylons used for taking materials from endocervix. 1

(A) Endocervical brush

(B) Exocervical brush

21. Name one routine cytological fixative. 1

Ans: 95% Ethyl Alcohol (Ethanol)

22. Which colour is taken by cytoplasm after hematoxylin-eosin staining? 1

Ans: Blue/green

23. Name one mounting agent. 1

Ans:

Attempt any 5 questions out of the given 7 questions of 2 marks each. 2×5=10

24. How can you prepare Leishman’s Stain ? 2

Ans: 0.15 g of powdered stain is dissolved in 100 mL of acetone-free methyl alcohol. Crystals

are ground to powder in a mortar, and alcohol is added a little at a time until the stain is dissolved. The stain can be used in an hour, but improves with time, provided it is kept in a glass

stoppered bottle.

25. What are the functions of components of WBC diluting fluid ? 2

Ans: Thymol (pinch) – prevents the growth of fungus.

Gentian violet stains the nuclei of leukocytes.

Glacial acetic acid lyses the red cells.

26. In which clinical conditions may reticulocyte count vary ? 2

Ans: Reticulocytosis (increased reticulocyte count) is seen in iron deficiency anemia on treatment, Megaloblastic anemia on treatment, and Hemolytic anemias.

Reticulocytopenia (decreased reticulocyte count) is observed in Aplastic anemia and PRCA (Pure red cell Aplasia).

27. Enumerate four equipments used for storage of blood. 2

Ans: Equipment used for the storage of blood

Blood storage cabinets
Plasma storage cabinets
Ultra-low freezers
Cryoprecipitate bath
Platelet agitator and incubator
Plasma thawing bath

28. Write down the functions of blood collection monitor. 2

Ans: A Blood collection monitor is used for the actual collection of blood. It can collect the desired volume of blood from the donor, which is either 350 or 450 ml. It has a visible volume display and flow rate. There is an audible alarm if the flow of blood is slow. There is a provision for automatic clamping when the volume is reached. After collection, this once again gives an audible alarm.

29. How can you say that a cytological fixative is good in nature ? 2

Ans: Properties of a good cytological fixative:

• It should not excessively shrink or swell cells.
• It should not distort or dissolve cellular components.
• It should help preserve nuclear details.
• It should improve optical differentiation and enhance the staining properties of the tissues and cell components.

30. Write down the functions of Carnoy’s Fixative. 2

Ans: This is a special-purpose fixative for haemorrhagic samples. The acetic acid in the fixative haemolyses the red blood cells. It is an excellent nuclear fixative as well as preservative for glycogen, but results in considerable shrinkage of cells. Carnoy’s fixative must be prepared fresh when needed and discarded after each use. It loses its effectiveness on long standing, and chloroform can react with acetic acid to form hydrochloric acid.

Answer any 5 questions out of the given 7 questions of 3 marks each. 3×5=15

31. Enumerate three problems encountered during staining. 3

Ans: Some of the problems encountered during staining:

Excessive blue stain is seen with Thick film, prolonged staining, inadequate washing, and too high an alkalinity of stain or diluent. Remedial actions are using less stain or more diluents, staining for a shorter time, and changing to a buffer with a low pH
Excessive pink stain is seen with Insufficient staining, Prolonged washing, mounting the cover slips before drying, too high an acidity of stain or buffer, or methyl alcohol, and the dye with improper polychromes (Try another lot)
Precipitate on the film occurs with Dirty slides, Drying of film during the staining procedure, Improper washing of the slides, Improper Filtration of the stain, and presence of dust on the slide or smear.

32. Explain the steps of making blood films. 3

Ans: EDTA blood or fresh blood without any anticoagulant can be used for making blood films.

One should make blood films as soon as possible after the collection of blood.

Clean glass slides (75mm x 25mm and around 1 mm in thickness) are taken, and a drop of blood is put on the slide about 1cm from one end in the centre line of the slide.
A spreader is then placed in front of the drop. At an angle of 300 to the slide.
The spreader is then moved back so that the drop of blood spreads out along the line of contact.
Next, the Spreader is moved forward with steady movement so that a film about 3 cm in length is made.

33. Write down the characteristic features of cryoprecipitate bath. 3

Ans: Cryoprecipitate baths are used for quick thawing of Plasma at + 4°C / + 37 °C and improve yields over conventional air thawing methods.

Cryoprecipitate bath is fabricated out of a sheet with a stainless steel inner chamber.
Refrigeration is achieved using a hermetically sealed compressor.
The temperature is controlled by a digital indicator cum controller.

Special features :

Suitable for 15 plasma bags with a rack holder.
Direct digital temperature indicator cum controller.
A stainless steel AISI 304 tank is resistant to corrosion.
Circulating pump to ensure uniform temperature within the bath.

34. Enumerate the parts of a microscope. 3

Ans: Parts of the microscope are :

1. The support system consists of the base or foot rest, which also holds the light source
2. The tube or the arm holds the optical system and also the coarse/fine adjustments.
3. The objectives are at the lower end of the tube, and the eyepieces are at the upper end.
4. The objectives are attached to the revolving nose piece and can be shifted. The objectives are 10x (low power), 40x (high power), and 100x (oil immersion).
5. Below the objectives is the stage that holds the object/slide. The stage has a central hole through which the light passes. The stage may be fixed or movable. Below the stage is the iris/diaphragm, which focuses the light.
6. The eye pieces are also of varying magnification; the commonly used one is 10x. The eyepieces are situated in the binocular tube.

35. Write down the uses of incubator. 3

Ans: These are mainly used for

1. Determination of enzymes in the specimen by endpoint reaction methods.
2. Determination of glucose, urea, uric acid, etc, by enzymatic methods.
3. Growing microorganisms on various culture media.
4. The right temperature for the immune antigen reaction.

36. Write down the advantages of PAP Smear. 3

Ans: Advantages of Pap Smear:

• It is painless and simple
• Does not cause bleeding
• Does not need anesthesia
• Can detect cancer and precancer
• Can identify non-specific and specific inflammations
• Can be carried out as an outpatient procedure

37. How can vaginal pool smear be made? 3

Ans: The aspiration can be performed after the introduction of an unlubricated speculum. The technique allows the collection of cells under direct vision from the posterior fornix pool. When a speculum is not employed the pipette is gently introduced in to the vagina until resistance is encountered. It is important to compress the suction bulb during the introduction of the pipette to avoid collecting the cellular material of the lower vaginal orgin. The cellular material is spread on a clean glass slide and fixed immediately.

Answer any 3 questions out of the given 5 questions of 5 marks each. 5×3=15

38. Write down the steps of the platelet count. 5

Ans: 0.02 ml. [20cumm] of the blood should be diluted with 1.98 ml of the diluting fluid. It is mixed well for 2 minutes before charging the Improved Neubauer Counting Chamber.

The charged chamber is placed in a petri dish with some moist filter paper (this prevents drying

and keeps the air moist under the petri dish). It is left undisturbed for 10 minutes. Platelets

settle on the surface of the counting chamber. Using the 40x objective and 10x eyepiece

with the condenser racked down, the platelets are seen as highly refractile particles. Count

the platelets in one or more sq. mm. It is important for greater accuracy to count at least

100 platelets.

39. How can the biomedical waste be transported inside and outside the hospital? 5

Ans: (A) Within the hospital

Waste routes must be designed to avoid the passage of waste through patient care areas.
Separate time should be earmarked for the transportation of dedicated wheeled containers, trolleys, or carts should be used trolleys or carts should be thoroughly cleaned and disinfected in the event of any spillage.
The wheeled containers should be designed so that the waste can be easily loaded, remains secured during transportation, does not have any sharp edges, and is easy to clean and disinfect

(B) Outside the hospital

Untreated biomedical waste should be transported only in such vehicles as may be authorized for the purpose by the competent authority, as specified by the Government under the Motor Vehicle Act, 1998.
The containers for transportation must be labeled with the “Biomedical Waste” symbol on both sides and the rear part.
Personnel involved in BMWM shall wear gloves, glasses, a lab coat, boots, and masks, and also shall be immunized against tetanus & Hepatitis B.

40. Explain the factors depending on the Ag-Ab reaction. 5

Ans: The red cells should be properly stored to achieve optimum reactivity. If the cells are frozen, the reactivity is better preserved. The reactivity is better in fresh cells. Thus, with dilute cell suspension, an increase in sensitivity is achieved, as the concentration of antibody in solution does not fall even when all cells are saturated with antibody. One drop (2-5%) of cell suspension is therefore found ideal to be added to two drops of serum.

41. Explain the method and interpretation of Rh antibody titers. 5

Ans: Method:

Label a row of tubes according to serum dilution 1 to 10 (1:2 to 1:5 12)
Place 1 volume (0.1 ml) or 1 drop of saline in all tubes except the first.
Add 1 volume (0.1ml) or 1 drop of serum to tubes 1 and 2 so that the first tube contains neat serum (1:1) and 2nd tube has 1 volume of serum in volume of saline (1:2). Using a clean pipette mix the contents of tube 2 (1: 2 dilution) without forming any bubbles and transfer one volume of mixture to tube 3 (1:4).
Continue the same process through all dilutions. Remove the I volume from the last tube and save for use if further dilutions are required.
Add 1 volume of 2-5% saline, and suspend appropriate red cells in each tube. (For Rh antibody titration, use ‘O’ positive pooled cells).
Mix well and incubate at RT for 60 minutes (IgM antibodies) and centrifuge all tubes at 1000 rpm for 1 minute.
Gently dislodge the cell button and record results using grades of agglutination reaction.
The last tube showing a positive reaction is considered the titre of the antibody.
For detection of IgG antibodies: arrange a 2nd row of tubes with the same serial dilution.
Incubate at 37 °C. Centrifuge and remove supernatant, incubate at 37 °C for 45 minutes. Wash with saline thrice.
Arrange fresh tubes and add 1 drop of AHG, and add the corresponding washed cells. Incubate at room temperature for 5 minutes, spin at 1000 rpm for 1 minute, and look for clumping.

Interpretation :

If there is clumping in the first row of test tubes, it indicates the presence of saline antibodies or IgM.
If there is clumping in the second row of test tubes, it indicates the presence of IgG antibodies.
The tube which shows minimum clumping shows the titration value; for eg, if the third tube shows clumping, then the titration value is 1 in 8 dilution positive.

42. Enumerate the equipment required for FNAC process. 5

Ans: Equipment required

• Aspiration is done using disposable needles of 21 gauge (external diameter approximately 0.6-1.0mm) attached to a 20ml syringe.

• The FNAC needles are available in a variety of lengths. Lengths of a to 1/2 inches are found to be adequate for most palpable masses.

• The 31/2 inches 22-gauge disposable needle is used for deep-seated soft-tissue masses.

• Ultrasound or computerized tomography (CT) guidance can be utilized whenever indicated.

• Multiple aspirates should be undertaken from different areas, in case of a large tumor, to improve the yield and overcome the problem of tumor heterogeneity.