Diapedesis is the movement of white blood cells through intact blood vessel walls into surrounding body tissue. It typically happens when an area of the body is injured or damaged, and an inflammation response is required. What role would you expect cell adhesion molecules to play in this process?

Question

A.  Cell adhesion molecules will allow the white blood cells to cling to one another to form a migrating clot.
B.  Cell adhesion molecules help white blood cells adhere to the blood vessel wall so that they can migrate across the wall and infiltrate into the underlying tissue.
C.  Cell adhesion molecules will allow the white blood cells to attach to the injured area so they become immobile.

Clarify Question
· What is the key concept addressed by the question?
· What type of thinking is required?

Gather Content
· What do you know about the role of adhesion molecules in white blood cell movement? What other information is related to the question?

Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?

Reflect on Process
· Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?

Answer 1

B.  Cell adhesion molecules help white blood cells adhere to the blood vessel wall so that they can migrate across the wall and infiltrate into the underlying tissue.

Clarify Question
· What is the key concept addressed by the question?
        o The question asks about the role of adhesion molecules in white blood cell movement.
· What type of thinking is required?
        o You are being asked to apply your knowledge about the role of adhesion molecules in white blood cell movement.

Gather Content
· What do you know about the role of adhesion molecules in white blood cell movement? What other information is related to the question?
        o Adhesion molecules allow two cells to attach to each other. In some tissues, these are very stable long term attachments. Blood cells need to be able to move, so adhesion molecule attachments are short term for these cells

Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
        o By binding to adhesion molecules on cells lining the blood vessels, white blood cells can crawl out of the blood vessel and into the surrounding tissues..

Reflect on Process
· Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
        o This question asked you to apply your knowledge about the role of adhesion molecules in white blood cell movement. If you got the correct answer, great job! If you got an incorrect answer, where did the process break down? Did you think that white blood cells binding to a region of damage would be immobile? Did you think that white blood cells would bind to each other in the blood stream?