The document presents a critical thinking exercise related to the human leukocyte antigen (HLA) system, asking participants to select the best answer for ten different statements. Each statement pertains to aspects of HLA, such as antibodies, classes of antigens, and its roles in transplantation and parentage testing. The exercise emphasizes the complexity and significance of HLA and its genetic variations.

1. HLA Critical Thinking Exercise
Select the best choice for 1-10 from the list A-I
1. HLA antibodies are ___
2. The human HLA system is similar to ___
3. Platelets express the ___
4. Class I HLA antigens are___
5. Class II HLA antigens are ___
6. Linked HLA genes on a chromosome are ___
7. Red cells have trace amounts of ___
8. The HLA system is useful in parentage testing because it is a ___
9. Mixed lymphocyte culture detects differences in ___
10. HLA is important in ___
Answers for 1-10:
A. Transplantation
B. Class II regions
C. Stimulated by multiple transfusions
D. Mouse H2 system
E. HLA-A and HLA-B
F. HLA-A, HLA-B and HLA-C
G. Haplotype
H. Bg antigens
J. Polymorphic system
K. HLA-DR, HLA-DP, and HLA-DQ