BIO PROLIFERATION GASEOUS EXCHANGE

Avery is studying the oxygen dissociation curve of haemoglobin in her biology class. What shape does this curve exhibit?

• Linear

• Circular

• Sigmoid

• Exponential

During a biology experiment, Anika measured the partial pressure of oxygen (PO2) in a controlled environment. At what PO2 is haemoglobin about 98% saturated with oxygen?

• 40 mm Hg

• 80 mm Hg

• 100 mm Hg

• 60 mm Hg

During a soccer match, William notices that his breathing becomes heavier as he runs. What happens to the affinity of haemoglobin for oxygen during exercise?

• It increases

• It remains the same

• It fluctuates

• It decreases

During a biology class, Abigail learned that at rest, the human body unloads a certain percentage of oxygen to tissues. How much oxygen is unloaded to tissues at rest?

• 48%

• 38%

• 28%

• 18%

During a biology class, Rohan learns about the effects of altitude on oxygen levels. He discovers that when the partial pressure of oxygen (PO2) falls to 40 mm Hg, the percentage of oxygen saturation in haemoglobin is affected. What is the percentage of oxygen saturation in haemoglobin at this level?

• 85%

• 75%

• 65%

• 95%

During a biology experiment, Abigail observed the effect of subunit cooperativity on oxygen release from haemoglobin in red blood cells. What did she conclude about this process?

• It has no effect

• It makes release harder

• It facilitates easier release

• It prevents release

During a physiology lecture, Mia learns about the Bohr effect. How does an increase in carbon dioxide concentration affect the oxygen affinity of haemoglobin?

• It fluctuates

• It decreases affinity

• It increases affinity

• It has no effect

Which type of receptor is responsible for sensing changes in carbon dioxide levels in the blood?

• baroreceptor

• peripheral chemoreceptor

• thermoreceptor

• photoreceptor

What happens when the pH of blood decreases during exercise?

• The respiratory rate decreases

• Peripheral and central chemoreceptors send signals to the inspiratory center to increase ventilation

• The diaphragm relaxes to reduce lung volume

• The aortic and carotid bodies stop detecting changes in pH

How do the diaphragm and external intercostal muscles respond to nerve impulses from the inspiratory center?

• They relax, decreasing thoracic cavity volume

• They contract, increasing thoracic cavity volume

• They contract, decreasing thoracic cavity volume

• They stop contracting