Final answer:
C5a and C3a are components of the complement system that act as chemoattractants, which means they attract monocytes and neutrophils to the sites of infection or injury. They increase the adherence of these white blood cells to blood vessel walls, facilitating their migration into tissue to engage and eliminate pathogens.
Step-by-step explanation:
Both C5a and C3a are components of the complement system, which plays a significant role in the body's immune response.
These molecules increase the adherence of monocytes and neutrophils to blood vessel walls. This process is essential because it helps these white blood cells to exit the bloodstream and enter infected or inflamed tissues.
C5a and C3a are also known as chemoattractants, meaning they attract immune cells to the sites of infection or injury through a process called chemotaxis.
The leukocytes, such as monocytes and neutrophils, respond to these chemical attractants, aiding their navigation towards the areas where they are most needed to combat pathogens and assist with the healing process.
In essence, C5a and C3a facilitate an important aspect of the immune response by guiding and activating immune cells to control infections, further assisted by cytokines like leukotrienes, which strengthen the attraction and recruitment of these cells to the site of infection.