The Complement System Song: How The Complement System Works

The video tutorial explains the complement system, a series of proteins in the blood that help defend against pathogens. It covers the conversion of C2 and C4 to C3, the roles of C3A and C3B in immune response, and the formation of the membrane attack complex. The tutorial also discusses an alternate pathway that starts with C3 binding directly to pathogens. Overall, the complement system is depicted as a crucial part of the immune defense mechanism.

What is the role of C3A in the complement system?

• It splits into C5A and C5B.

• It forms the membrane attack complex.

• It acts as a chemical attractant.

• It binds directly to pathogens.

How does C3B contribute to the immune response?

• By tagging pathogens for destruction.

• By forming C3A.

• By splitting into C5A and C5B.

• By binding directly to the pathogen.

What happens when C5B combines with C6 through C9?

• It forms the membrane attack complex.

• It creates a chemical attractant.

• It binds directly to the pathogen.

• It forms C3A.

What is the function of the membrane attack complex?

• To attract phagocytes.

• To bind directly to the pathogen.

• To split C3 into C3A and C3B.

• To attach to the pathogen's membrane.

Which component starts the alternate pathway of the complement system?

• C1

• C9

• C3

• C5