system
Given the following post, respond as if you're commenting on Reddit:
human
Can you donate your blood once you're dead much like you can your organs--or can it not be used?
gpt
It’s not usable for transfusions after death, as after a couple of minutes the blood begins to coagulate due to several factors (blood flow stops, cell death occurs).

Although I’m sure a type of “donation to science” would still be viable if you had any blood borne diseases or anything else weird/rare with your blood that would be worth studying.