PATHOLOGY

PATHOLOGY MCQ

IMMUNE RESPONSE

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
How does the body tell the difference between its own cells and foreign cells?
A
memory cells recognize different kins of cells
B
foreign cells have different DNA
C
it recognizes antigens on the cell surface
D
it cannot differentiate, so it destroys all cells in the bloodstream
Explanation: 

Detailed explanation-1: -Antigens are markers that tell your body that something is foreign. Your immune cells make antibodies to recognize and destroy harmful antigens. In fact, you can think of antigens as antibody generators. Antibodies are very specific to the antigens they recognize and destroy.

Detailed explanation-2: -That is, the immune system must be able to distinguish what is nonself (foreign) from what is self. The immune system can make this distinction because all cells have identification molecules (antigens) on their surface. Microorganisms are recognized because the identification molecules on their surface are foreign.

Detailed explanation-3: -They do this by recognising substances called antigens on the surface of the microbe, or in the chemicals they produce, which mark the microbe or toxin as being foreign. The antibodies then mark these antigens for destruction.

Detailed explanation-4: -The immune system recognizes invaders by their antigens, which are proteins on the surface of the invading cells (see Figure 1). Every cell or substance has its own specific antigens, and a person’s cells carry “self-antigens” that are unique to that individual.

Detailed explanation-5: -Cells that belong in the body carry specific markers that identify them as “self” and tell the immune system not to attack them. Once the immune system recognizes a pathogen as “non-self, ‘’ it uses cellular and chemical defenses to attack it.

There is 1 question to complete.