Activity 5 Laboratory

Question 1

Laboratory Activity 5

Answer 1

CLOT RETRACTION TIME

Question 2

Within —– after whole blood is allowed to clot in a clean glass tube at —-

Answer 2

1 hour, 37OC

Question 3

—— is expressed and the —- becomes denser

Answer 3

Serum,clot

Question 4

This retraction process is ——-, by which time it occupies almost —- of the original blood volume

Answer 4

maximal at 24 hours
half

Question 5

Specimen Needed

Answer 5

Fresh whole blood

Question 6

PROCEDURE

Answer 6

Modified MacFarlane Serum method

Question 7

1. Collect ——–. Note the time of collection.

Answer 7

5 ml of venous blood samples

Question 8

2. Dispense into a ——- noting exact amount of blood used.

Answer 8

graduated centrifuge tube

Question 9

3. Place an applicator stick at the —-

Answer 9

center of tube

Question 10

4. Incubate test tubes at —- in a water bath —-

Answer 10

37 0C
for 2 hours

Question 11

5. Examine and record degree of retraction ——

Answer 11

(partial, complete, or no retraction)

Question 12

6. Pull applicator stick with ——– and describe the clot.

Answer 12

clotted blood

Question 13

7. Serum expressed is centrifuged for —– at —-

Answer 13

3-5 minutes
3,500 rpm

Question 14

Computation of serum expressed

Answer 14

a. Volume of Serum = total volume of serum in tube – volume of packed red cells
b. Then: % serum expressed = Vol of serum in ml X100
Vol of blood used in ml.