Across
- 2. – The main muscle involved in breathing, contracts to draw air into the lungs.
- 4. – The widening of blood vessels to increase blood flow.
- 7. – The number of times the heart beats per minute.
- 9. – Muscles between the ribs that assist in the expansion and contraction of the thoracic cavity.
- 12. – Specialized sensor that detects changes in blood CO₂, pH, and O₂ levels.
- 15. – The process of moving air into and out of the lungs.
- 16. – The blood pressure measured when the heart is relaxed between beats.
- 17. – The gas exchanged in the alveoli and transported to the muscles via red blood cells.
- 18. – Related to the lungs; describes circulation between the heart and lungs.
- 19. – Tiny air sacs in the lungs where gas exchange occurs.
Down
- 1. – The node that acts as the pacemaker of the heart by initiating electrical impulses.
- 3. – The smallest blood vessels where exchange of gases, nutrients, and wastes takes place.
- 5. – The maximum volume of air the lungs can hold (vital capacity + residual volume).
- 6. – Part of the brainstem that controls the basic rhythm of breathing.
- 8. – A blood vessel that carries blood away from the heart under high pressure.
- 10. – A protein in red blood cells that binds to and transports oxygen.
- 11. – Refers to the intercostal muscles that contract during inhalation to expand the chest.
- 13. – The amount of air inhaled or exhaled in a normal breath.
- 14. – The passive movement of gases from areas of high to low partial pressure.
- 15. – A blood vessel that carries blood toward the heart under low pressure.