Answer:

because oxygenated blood flows in arteries and deoxygenated blood flows in veins.

Explanation:

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ᴏxʏɢᴇɴᴀᴛᴇᴅ ʙʟᴏᴏᴅ ʀᴇꜰᴇʀꜱ ᴛᴏ ᴛʜᴇ ʙʟᴏᴏᴅ ᴛʜᴀᴛ ʜᴀꜱ ʙᴇᴇɴ ᴇxᴘᴏꜱᴇᴅ ᴛᴏ ᴏxʏɢᴇɴ ɪɴ ᴛʜᴇ ʟᴜɴɢꜱ. ᴅᴇᴏxʏɢᴇɴᴀᴛᴇᴅ ʙʟᴏᴏᴅ ʀᴇꜰᴇʀꜱ ᴛᴏ ᴛʜᴇ ʙʟᴏᴏᴅ ᴛʜᴀᴛ ʜᴀꜱ ᴀ ʟᴏᴡ ᴏxʏɢᴇɴ ꜱᴀᴛᴜʀᴀᴛɪᴏɴ ʀᴇʟᴀᴛɪᴠᴇ ᴛᴏ ʙʟᴏᴏᴅ ʟᴇᴀᴠɪɴɢ ᴛʜᴇ ʟᴜɴɢꜱ. ... ᴏxʏɢᴇɴᴀᴛᴇᴅ ʙʟᴏᴏᴅ ꜰʟᴏᴡꜱ ᴀᴡᴀʏ ꜰʀᴏᴍ ᴛʜᴇ ʜᴇᴀʀᴛ. ᴅᴇᴏxʏɢᴇɴᴀᴛᴇᴅ ʙʟᴏᴏᴅ ꜰʟᴏᴡꜱ ᴛᴏᴡᴀʀᴅꜱ ᴛʜᴇ ʜᴇᴀʀᴛ.

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