Chapter 15:Gaseous Exchange In Humans Flashcards
Flashcard 1:
Q: What is breathing?
A: The physical process of inhaling oxygen-rich air from the atmosphere into the lungs and exhaling carbon dioxide-rich air from the lungs into the atmosphere.
Flashcard 2:
Q: What is respiration?
A: The release of energy from breaking down food substances (glucose) in all living cells.
Flashcard 3:
Q: What are the features of gas exchange surfaces in humans?
A: Large surface area, thin surface, good blood supply, and good ventilation with air.
Flashcard 4:
Q: Where does gas exchange take place in humans?
A: In the alveoli (alveolus).
Flashcard 5:
Q: What are the characteristics of alveoli that make them efficient for gas exchange?
A: Very large surface area, thin walls (one cell thick), moist surface, good blood supply, and good ventilation with air.
Flashcard 6:
Q: What is the function of external intercostal muscles during breathing?
A: They contract to move the rib cage upwards and outwards to allow oxygen-rich air to flow into the lungs, and relax to move the rib cage inwards and downwards to allow carbon dioxide-rich air to flow out of the lungs.
Flashcard 7:
Q: What is the function of internal intercostal muscles during breathing?
A: They relax to move the rib cage upwards and outwards to allow oxygen-rich air to flow into the lungs, and contract to move the rib cage inwards and downwards to allow carbon dioxide-rich air to flow out of the lungs.
Flashcard 8:
Q: What is the function of the diaphragm during breathing?
A: It contracts and flattens to increase the volume of the chest cavity to allow oxygen-rich air to flow into the lungs, and relaxes to form a dome shape to decrease the volume of the chest cavity to allow carbon dioxide-rich air to flow out of the lungs.
Flashcard 9:
Q: What is the role of cartilage in the trachea?
A: To keep the trachea (windpipe) open to prevent it from collapsing during breathing.
Flashcard 10:
Q: What is the composition of nitrogen in inspired and expired air?
A: 78% in both inspired and expired air, because it is insoluble and not absorbed into the blood.
Flashcard 11:
Q: What is the composition of oxygen in inspired and expired air?
A: 21% in inspired air and 16% in expired air, because it is absorbed into the blood and used in respiration.
Flashcard 12:
Q: What is the composition of carbon dioxide in inspired and expired air?
A: 0.04% in inspired air and 4% in expired air, because it is a waste product of respiration expelled from the lungs.
Flashcard 13:
Q: How does the temperature of inspired and expired air differ?
A: Inspired air has a variable temperature, while expired air is warmer as the body heats it up to body temperature.
Flashcard 14:
Q: How does the water vapor content of inspired and expired air differ?
A: Inspired air has variable water vapor content, while expired air is saturated with water vapor as it evaporates from the surface of the alveoli.
Flashcard 15:
Q: How is lime water used to test for the presence of carbon dioxide?
A: Clear lime water turns milky/cloudy in the presence of carbon dioxide.
Flashcard 16:
Q: What is the practical procedure for testing the concentration of carbon dioxide in inspired and expired air?
A: Bubble room air through lime water in one beaker and exhaled air through lime water in another beaker, then observe and record the results.
Flashcard 17:
Q: What happens to lime water when carbon dioxide is bubbled through it?
A: It produces calcium carbonate, making the lime water appear cloudy or milky.
Flashcard 18:
Q: What happens to the breathing rate and depth during vigorous exercise?
A: Both increase to allow more oxygen to be supplied to active muscles and more carbon dioxide to be expelled from the body.
Flashcard 19:
Q: How can you investigate the effects of exercise on breathing rate?
A: Measure the breathing rate at rest, perform physical activity (e.g., jumping up and down), and then measure the breathing rate again.
Flashcard 20:
Q: What harmful substances are found in tobacco smoke?
A: Tar, nicotine, and carbon monoxide.
Flashcard 21:
Q: How does tar affect the gas exchange system?
A: It stimulates extra mucus production, narrows air passages, restricts airflow, contains carcinogenic chemicals, and can cause lung cancer and emphysema.
Flashcard 22:
Q: How does nicotine affect the gas exchange system?
A: It is addictive, causes narrowing of arteries, increases blood pressure, and makes platelets sticky, leading to blood clots.
Flashcard 23:
Q: How does carbon monoxide affect the gas exchange system?
A: It combines with hemoglobin in red blood cells, preventing oxygen transport and causing shortness of breath.
Flashcard 24:
Q: What is COPD and how is it related to smoking?
A: COPD is a lung disease that makes it difficult to breathe due to obstructed airflow, and smoking increases the risk of developing COPD, including lung cancer and emphysema.
