In comparing the genomes of humans and those of other higher primates, it is seen that humans have a large metacentric pair we call chromosome #2 among our 46 chromosomes, while the other primates of this group have 48 chromosomes and any pair like the human #2 pair is not present; instead the primate groups each have two pairs of midsize acrocentric chromosomes. What is the most likely explanation?

#Question id: 11077

#Unit 7. System Physiology – Animal

A person’s normal tidal volume is 400 ml with a dead space of 100 ml. The respiratory rate is 12 breaths/min. The person is placed on ventilator for surgery and the tidal volume is 700 with a rate of 12. What is the approximate alveolar Pco2 for this person?

#Question id: 11079

#Unit 7. System Physiology – Animal

The diffusing capacity of a gas is the volume of gas that will diffuse through a membrane each minute for a pressure difference of 1 mm Hg. Which of the following gases is often used to estimate the oxygen diffusing capacity of the lungs?

#Question id: 11080

#Unit 7. System Physiology – Animal

The O2-CO2 diagram here shows a ventilation-perfusion ratio line for the normal lung. Which of the following best describes the effect of decreasing ventilation-perfusion ratio on the alveolar Po2 and Pco2?

#Question id: 11081

#Unit 7. System Physiology – Animal

In which of the following conditions is alveolar Po2 increased and alveolar Pco2 decreased?

#Question id: 11090

#Unit 7. System Physiology – Animal

An aviator is flying at 30,000 ft where the barometric pressure is 226 mm Hg. He is breathing 100% oxygen, his alveolar PCO2 is 40 mm Hg, and his alveolar water vapor pressure is 47 mm Hg. What is the alveolar PO2 of the aviator (in mm Hg)? (Assume that the respiratory quotient is equal to 1.)

#Question id: 11091

#Unit 7. System Physiology – Animal

A diver is breathing 10% O2 at a pressure of 2000 mm Hg. The diver’s body temperature is 37°C, and PCO2 = 32 mm Hg. What is the alveolar PO2?