Why do octopuses have three hearts?
Show answer & explanation
Answer: Two for gills, one for body
Two for gills, one for body ✓ — Correct! Two branchial hearts pump blood through the gills to pick up oxygen. The main systemic heart pumps oxygenated blood to the body. This helps their copper-based blue blood deliver oxygen efficiently!
Backup if one heart fails — Wrong. The three hearts aren't backups—each has a specific job. Losing one would seriously impair the octopus's circulation system.
Each controls different arms — Wrong. Hearts don't control arms. Octopuses do have neurons in their arms for some independent movement, but hearts only pump blood.
Go deeper: Branchial heart
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