Why Do Clotted Specimens Yield Positive DAT Results with Anti-C3

question 3

Multiple Choice

Why do clotted specimens yield positive DAT results with anti-C3 in the presence of a benign cold autoagglutinin?

• A) Complement is inhibited due to calcium chelation.
• B) Complement can be activated in vivo.
• C) Complement can be activated in vitro.
• D) Complement is activated in the absence of fibrinogen.

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Definitions:

Stable Isotope

Non-radioactive forms of atoms that have the same number of protons but a different number of neutrons, used in various scientific applications to study and trace processes.

Radiometric Dating

A method for determining the age of an object containing organic material by measuring the levels of various isotopes within it.

Earth's Crust

The outermost layer of the Earth, composed of a variety of rocks and minerals; it forms the continents and ocean basins.

Fault

A fracture or zone of fractures between two blocks of rock, which can cause large scale earth movements.