Following statements are regarding to mechanism of kinesin-1 movement.

A. Initially leading head tightly bound to the microtubule and not bound by any nucleotide, while the trailing head is weakly bound to the microtubule and has ADP bound.

B. Binding of ATP induces a conformational change causing the linker to swing forward and dock into the head. This motion swings the former trailing head to become the leading head.

C. Binding of ATP induces a conformational change causing the linker to swing forward and dock into the head. This motion swings the former leading head to become the trailing head.

D. When leading head releases ADP and coordinately the trailing head hydrolyzes ATP to ADP + Pi. Pi is released and the linker becomes undocked.

E. When trailing head releases ADP and coordinately the leading head hydrolyzes ATP to ADP + Pi. Pi is released and the linker becomes undocked.

Which of the following combination is correct?

#Question id: 11067

#Unit 7. System Physiology – Animal

A preterm infant has a surfactant deficiency. Without surfactant, many of the alveoli collapse at the end of each expiration, which in turn leads to pulmonary failure. Which of the following sets of changes are present in the preterm infant, compared to a normal infant?

#Question id: 11068

#Unit 7. System Physiology – Animal

A patient has a dead space of 150 ml, functional residual capacity of 3 L, tidal volume of 650 ml, expiratory reserve volume of 1.5 L, total lung capacity of 8 L, and respiratory rate of 15 breaths/min. What is the residual volume?

#Question id: 11069

#Unit 7. System Physiology – Animal

A 22-year-old woman inhales as much air as possible and exhales as much air as she can producing the spirogram shown in the figure. A residual volume of 1.0 L was determined using the helium dilution technique. What is her functional residual capacity (in liters)?

#Question id: 11070

#Unit 7. System Physiology – Animal

A patient has a dead space of 150 ml, functional residual capacity of 3 L, tidal volume of 650 ml, expiratory reserve volume of 1.5 L, a total lung capacity of 8 L, respiratory rate of 15 breaths/min. What is the alveolar ventilation?

#Question id: 11071

#Unit 7. System Physiology – Animal

At the end of inhalation, with an open glottis, the pleural pressure is

#Question id: 11072

#Unit 7. System Physiology – Animal

The following diagram shows pulmonary airway resistance expressed as a function of pulmonary volume. Which relationship best describes the normal lung?