BRAINCAKEBlood Clotting
If the skin is reached, the blood clots rapidly to seal the wound, prevent loss of blood and prevent pathogens from entering the body.
When platelets come into contact with collagen in the skin or the wall of damaged blood vessels, they are activated. Activated platelets change shape and stick to the walls of the damaged blood vessels.
Exposed collagen fibres release ATP and other inflammatory mediators to attract macrophages to the site.
Sign in free to see the rest of this lesson, the R.E.C.I.P.E. recall steps and the quiz
BrainCake is free. Make an account in seconds and pick up where this page stops.
Key terms in this lesson
- ATP
- Adenosine triphosphate, a nucleotide that acts as the immediate energy source of a cell, releasing energy when hydrolysed to ADP and inorganic phosphate.
- pathogen
- A microorganism that causes disease.
More in Communicable Diseases
- Factors Affecting Transmission in Animals
- Transmission of Pathogens Between Plants
- Plant Defences against Pathogens
- Mammals - non-Specific Defences
- Inflammatory Response
- Fevers
- Phagocytosis
- Counting Blood Cells
All 40 lessons in Communicable Diseases · All OCR AS-level Biology topics