One evening, after hearing Neptune explain that he felt like someone was watching him in the bath, God puts in an order for an "animal that's watching even though it looks like nothing's there". As always, the order is ridiculous and makes the design team agonize,
but then they decide to experiment with the squid that Pluto designed in the past...
The oxygen transporter, hemoglobin, 
is the reason blood is red.
احمرار الدم هو من مادة الهيموجلوبين الناقلة للأكسجين
La sangre es roja por la hemoglobina.
La sangre es roja por la hemoglobina.
Le sang rouge est dû
à l’hémoglobine transportant l’oxygène.
Il colore rosso del sangue è dovuto all'emoglobina,
 la proteina che trasposta l'ossigeno.
A hemoglobina transporta o oxigênio
e faz o sangue ser vermelho.
Кровь красная из-за гемоглобина,
переносчика кислорода.