Question

Need answers to all please :)

17) What would be the possible titers of antibodies against a pathogenic antigen, generated throughout a successful immunization protocol that includes 3 injections with a two-week interval?

1:100, 1:400, 1:36000

1:100, 1:100, 1:200

1:400, 1:200 1:100

1:2000 1:1000 1:4000

18) All of the following white blood cells can be observed accurately with a light microscope except:

neutrophils

B cells

lymphocytes

monocytes

eosinophils

19) The colonies occasionally observed within the plaque formed by a tear on a bacterial lawn may reflect

Contamination

Growth of a resistant bacteria

A high dilution of tears

All of the above are possible.

a+b

20) Which of the following criteria can best distinguish between the different types of granulocytes in a blood smear stained with Giemsa

nucleus morphology

number of granules

color of granules

cytoplasm:cell ratio

cell size

21) Which of the following criteria can not differentiate between white blood cells using flow cytometry?

cell size

cells granularity

expression of CD45

nucleus size

22) Cell viability can be estimated with both Trypan blue staining and CFSE.

Which of the following is correct?

Trypan blue will stain dead cells while CFSE will stain live cells

Trypan blue will stain live cells while CFSE will stain dead cells

both Trypan Blue and CFSE stain dead cells

Both trypan Blue and CFSE stain live cells

Answer 1

17) The possible titer could be 1:100, 1:400, 1:36000 as the body is given with antigens the antibody will increase .

19) The answer is growth of resistant bacteria, plaques usually lyses the cells within them, since the bacteria is resistant to plaque as its seen inside.

20)Giemsa stain is used to differentiate nuclear and cytoplasmic morphology of the various blood cells . Since cytoplasmic morphology is not there the answer is nuclear morphology.

21)Flow Cytometry can measure size and ngranularity , protien expression also hence it can measure expression of CD45. Nucelaus size cannot be measured.

22) Both trypan Blue and CFSE stain live cells.