blood composition
red blood cells
white blood cells
plasma
platelets
involved in blood clotting
transports oxygen
haemoglobin combine with oxygen and carry them to the rest of the body
biconcave shape for more surface area
they have no nucleus, more space for haemoglobin
25% are lymphocytes
70% are phagocytes
phagocytes ingest and destroy the pathogen.
- they surround the pathogen
- they wrap them into a vacuole shape
- they release enzymes to destroy the pathogen
they produce antibodies
they can stick on to the pathogen and make it burst and die
they can mark and clump the pathogens in one clump for phagocytes to destroy
they can neutralise the toxins produed by the pathogens
things they transport
they make up 55% of blood
urea
heat
carbon dioxide
from respiring cells to the lung for exhalation
from cells to kidney
hormones
they are secreted into plasma to be transported to other organs
they absorb and release it