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Got source for one tagged citation needed, and its in https://www.britannica.com/science/hemoglobin. Please edit inside if yo're an administrator or when protection goes off. BaronHerzog (talk) 04:05, 2 March 2023 (UTC)[reply]

Blood Color - Hemoglobin 38.7.66.122 (talk) 20:55, 20 February 2024 (UTC)[reply]

I would add the sentence "Novel edidence 38.7.66.122 (talk) 20:56, 20 February 2024 (UTC)[reply]

Lead section is super long. Could use some help cutting it down and redistributing information to other parts of the page. Just-a-can-of-beans (talk) 22:56, 14 January 2024 (UTC)[reply]

Sir Marios the II claims that blood is a tissue but in reality it is an organ that is made of red chlorophyll pigments— Preceding unsigned comment added by 150.228.63.69 (talk) 09:17, 25 September 2025 (UTC)[reply]

Change that blood is a connective tissue into blood is an organ system that is made of red chlorophyll pigments 150.228.63.69 (talk) 09:15, 25 September 2025 (UTC)[reply]

 Not done: please provide reliable sources that support the change you want to be made. M.Bitton (talk) 11:59, 25 September 2025 (UTC)[reply]

The redirect Blood organ has been listed at redirects for discussion to determine whether its use and function meets the redirect guidelines. Readers of this page are welcome to comment on this redirect at Wikipedia:Redirects for discussion/Log/2025 October 31 § Blood organ until a consensus is reached. consarn _{(talck) (contirbuton s)} 11:59, 31 October 2025 (UTC)[reply]