B6.3 Flashcards
What is the main barrier to infection?
Your skin
What happens when your skin is cut or grazed?
Pathogens enter the body
How do u prevent micro organisms from entering?
The skin needs to seal a cut by forming a scab
Why are platelets essential?
Helps blood to clot.
How are scabs formed?
The skin is cut and starts to bleed so the blood leaks out of the body.
The platelets change the blood protein fibrinogen into fibrin. This forms a network of fibres in the cut.
Red blood cells are trapped in the fibres. This forms a blood clot.
The clot hardens to form a scab. This keeps the skin clean and gives it time to heal. In time the scab falls off.
What is a phagocyte?
These cells engulf micro organisms. They then makes enzymes that digest the micro organism.
What’s a lymphocyte?
They make antibodies or antitoxins
What are antibodies?
They are proteins that bind to antigens on the surface of microorganisms and once they are bound together, the pathogen can be ingested by a phagocyte cell and destroyed.
