This lesson plan outlines how to teach students about the journey of oxygen from the atmosphere to tissues. It will develop students' knowledge, skills, and attitudes through lecture, demonstration, group discussion, and evaluation. Key concepts include: 1) Oxygen diffuses into the lungs and is absorbed by hemoglobin in red blood cells. 2) Red blood cells are disc-shaped and lack a nucleus, allowing them to carry more hemoglobin. 3) Hemoglobin transports oxygen through iron as oxyhemoglobin, which dissociates into oxygen and hemoglobin in tissues due to concentration differences.