A Scientist Is Interested in the Mechanisms by Which Leukocytes

question 121

Multiple Choice

A scientist is interested in the mechanisms by which leukocytes traffic to sites of inflammation and infection.  She finds that endothelial cells increase the expression of certain cell surface molecules in response to cytokines to allow for leukocyte trafficking.  She subsequently creates a knockout mouse that has a deletion in the platelet endothelial cell adhesion molecule 1 (PECAM-1) gene.  The protein product of this gene is mainly localized to specific areas on the endothelial cells.  Absent expression of this gene will most likely affect which of the following neutrophil functions?

• A)Crawling
• B)Margination
• C)Rolling
• D)Tight adhesion
• E)Transmigration

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Definitions:

Obsessed With Food

A state where an individual's thoughts and actions are excessively focused on food, its consumption, and its effects.

Human Behaviors

Patterns of actions or reactions of humans, generally in response to stimuli from the environment or from internal thoughts.

Rigidly Patterned

Describes behavior or processes that are strictly regular and unvarying, often adhering to a fixed or inflexible structure or sequence.

Instincts

Innate, typically fixed patterns of behavior in animals in response to certain stimuli.