Blood Flow Pathway: Heart to Zygomaticus Muscles and Return

The path of blood from the heart to the left zygomaticus muscles and back to the heart is as follows:

1. Heart: The blood starts from the left ventricle of the heart.

2. Aorta: The blood is pumped out of the heart through the ascending aorta.

3. Brachiocephalic trunk: The ascending aorta branches into the brachiocephalic trunk, which gives rise to the right common carotid artery and the right subclavian artery.

4. Right common carotid artery: The right common carotid artery travels up the neck and branches into the right internal carotid artery and the right external carotid artery.

5. Right external carotid artery: The right external carotid artery supplies blood to the face and scalp. It gives off several branches, including the transverse facial artery.

6. Transverse facial artery: The transverse facial artery runs across the face and supplies blood to the zygomaticus muscles, which are responsible for raising the corners of the mouth.

7. Veins: The blood from the zygomaticus muscles drains into the facial vein, which eventually empties into the internal jugular vein.

8. Internal jugular vein: The internal jugular vein carries blood from the head and face back to the heart.

9. Superior vena cava: The internal jugular vein joins the subclavian vein to form the superior vena cava, which empties into the right atrium of the heart.

10. Right atrium: The blood flows from the superior vena cava into the right atrium of the heart.

11. Right ventricle: The blood is then pumped from the right atrium into the right ventricle.

12. Pulmonary artery: The blood is pumped out of the right ventricle through the pulmonary artery.

13. Lungs: The pulmonary artery carries the blood to the lungs, where it picks up oxygen and releases carbon dioxide.

14. Pulmonary veins: The oxygenated blood returns to the heart through the pulmonary veins, which empty into the left atrium.

15. Left atrium: The blood flows from the pulmonary veins into the left atrium of the heart.

16. Left ventricle: The blood is then pumped from the left atrium into the left ventricle.

17. Aorta: The blood is pumped out of the heart through the ascending aorta, and the cycle repeats.