Imagine you are a red blood cell sitting in the right atria of the heart. in your laboratory journal, write a paragraph that describes what happens to this red blood cell as it moves through the body. what structures will it pass through? how will it interact with oxygen? think back to unit 3 and make sure to include the word hemoglobin in your response.

A red blood cell, starting from the heart's right atria is a deoxygenated red blood cell containing unoxygenated hemoglobin or carbaminohemoglobin (since it contains carbon dioxide instead of oxygen). This gives deoxygenated blood its chocolate-brown color. This red blood cell will be pumped to the right ventricle through the tricuspid valve then to the pulmonary circulation through the pulmonary valve. In the pulmonary circulation, there will be gas exchange in the alveoli of the lungs wherein carbon dioxide will dissociate from the hemoglobin and will be replaced with oxygen. Hemoglobin will now be called oxyhemoglobin and this gives oxygenated blood its bright red color. Hemoglobin in red blood cell can hold up to 4 molecules of oxygen. Now, from the pulmonary circulation, the red blood cell will go to the left atria through the pulmonary veins then to the left ventricle through the mitral valve then to the aorta and systemic circulation through the aortic valve. In the systemic circulation, oxygen is replaced by carbon dioxide (end-products of cellular respiration) and then will be transported back to the heart, particularly in the right atrium. This is called the cardiac cycle.