Section: Coach Breath — How Breath Works
This section covers Chapter 1, Lessons 1.1 through 1.4.
Part A — Vocabulary (20 points, 2 points each)
Select the best answer for each question.
1. The diaphragm is:
A) A small bone in the chest B) A large dome-shaped muscle at the bottom of the chest cavity — the primary muscle of breathing C) A part of the lungs D) Located in the abdomen but not involved in breathing
2. Alveoli are:
A) Tiny veins in the lungs B) Microscopic balloon-like air sacs at the end of the smallest airways, where gas exchange occurs C) Muscles in the chest wall D) Cells lining the nose
3. Gas exchange refers to:
A) Exchange of air between two people B) The movement of oxygen and carbon dioxide between air and blood, and between blood and tissues C) Exchange of stomach gases D) A property of the atmosphere
4. Hemoglobin is:
A) A protein in plasma B) An iron-containing protein inside red blood cells that binds oxygen C) A type of antibody D) A digestive enzyme
5. Hypercapnia is:
A) Low blood pressure B) Elevated levels of carbon dioxide in the blood C) Excess oxygen D) Low sodium
6. Hypocapnia is:
A) Low oxygen levels in the blood B) Reduced levels of carbon dioxide in the blood, often from hyperventilation C) A vitamin deficiency D) A type of anemia
7. Chemoreceptors are:
A) Chemicals that produce smells B) Specialized sensors that detect chemical changes in the body, including CO2 and pH levels C) Cells in the nose D) Found only in the heart
8. Nitric oxide in the context of breathing:
A) Is a pollutant B) Is a small signaling molecule produced in the sinuses during nasal breathing C) Is produced only by exhalation D) Has no role in respiration
9. The parasympathetic nervous system is the:
A) "Activation" branch of the autonomic system B) "Recovery" branch of the autonomic system C) Same as the motor system D) Conscious system you control directly
10. Heart Rate Variability (HRV) refers to:
A) Average heart rate over a day B) The variation in time between consecutive heartbeats — generally a marker of autonomic function C) Heart rate during exercise only D) A measure of pulse strength
Part B — Concept Comprehension (20 points, 2 points each)
Select the best answer for each question.
11. The primary muscle of breathing is the:
A) Heart B) Diaphragm C) Intercostals D) Trachea
12. Gas exchange in the lungs happens primarily across the walls of the:
A) Trachea B) Bronchi C) Alveoli D) Pleural cavity
13. Air moves into your lungs because:
A) The lungs actively suck it in B) The chest cavity expands, lowering pressure inside the lungs C) Oxygen is pulled in by hemoglobin D) The diaphragm pushes air down the throat
14. The main driver of the everyday urge to breathe is:
A) Falling oxygen B) Rising carbon dioxide C) Falling blood pressure D) Rising body temperature
15. The chemoreceptors that most strongly drive normal breathing rhythm are located in the:
A) Lungs B) Heart C) Brainstem (medulla) D) Kidneys
16. Compared to mouth breathing, nasal breathing:
A) Provides more total oxygen per breath B) Filters, warms, humidifies the air, and produces nitric oxide C) Is used only by athletes D) Is always faster than mouth breathing
17. The autonomic nervous system has two main branches:
A) Voluntary and involuntary B) Sensory and motor C) Sympathetic and parasympathetic D) Central and peripheral
18. Slow exhalation tends to:
A) Activate the sympathetic nervous system B) Increase blood pressure C) Engage the parasympathetic nervous system through the vagus nerve D) Reduce oxygen delivery to the brain
19. The Bohr effect describes how hemoglobin:
A) Holds oxygen more tightly in acidic tissues B) Releases oxygen more easily in tissues where CO2 is being produced C) Cannot bind to oxygen below pH 7.4 D) Carries more nitric oxide than oxygen
20. Coach Breath describes breath as:
A) Only a passive function B) The bridge between the autonomic nervous system and conscious choice C) Important only for athletes D) Identical to circulation
Part C — Application (30 points, 6 points each)
Write 2-4 complete sentences for each question. Show your reasoning.
21. Explain how the diaphragm and pleural cavity work together to move air into the lungs. What physical principle does this depend on?
22. Describe what happens chemically when carbon dioxide builds up in the blood, and why this leads to the urge to breathe.
23. Why does hyperventilation (rapid, deep breathing) sometimes cause lightheadedness or tingling even when oxygen is plentiful?
24. Coach Breath says breath is "the bridge" between the autonomic nervous system and conscious choice. Explain what this means in your own words and identify one practical implication.
25. Describe two physiological reasons nasal breathing might support better gas exchange than mouth breathing during ordinary, low-effort activity. Use specific chapter terms.
Continue to the next section.