#Question id: 2582
#Unit 2. Cellular Organization
Following statements are regarding to dynamics of actin filaments.
A. When the concentration of G-actin is above the Cc, the filament end will grow; when it is less than the Cc, the filament will shrink.
B. ATP–G-actin is added much faster at the (+) end than at the (−) end, resulting in a lower critical concentration at the (+) end than at the (−) end.
C. At steady state, actin subunits treadmill through a filament. ATP-actin is added at the (+) end, ATP is then hydrolyzed to ADP and Pi, Pi is lost, and ADP-actin dissociates from the (−) end.
D. ATP–G-actin is added much faster at the (-) end than at the (+) end, resulting in a lower critical concentration at the (-) end than at the (+) end.
E. At steady state, actin subunits treadmill through a filament. ATP-actin is added at the (-) end, ATP is then hydrolyzed to ADP and Pi, Pi is lost, and ADP-actin dissociates from the (+) end.
Which of the following statements are correct?
#Question id: 11758
#Unit 7. System Physiology – Animal
In normal kidneys, which of the following is true of the osmolarity of renal tubular fluid that flows through the early distal tubule in the region of the macula densa?
#Question id: 2984
#Unit 2. Cellular Organization
Certain unicellular eukaryotes, including diatoms and some yeasts, have mechanisms of nuclear division that may resemble intermediate steps in the evolution of mitosis. Which of the following is a characteristic feature of nuclear division in these organisms?
#Question id: 26380
#Unit 3. Fundamental Processes
#Question id: 11082
#Unit 7. System Physiology – Animal
A 67-year-old man has a solid tumor that pushes
against an airway partially obstructing air flow to the distal alveoli. Which
point on the ventilation-perfusion line of the O2-CO2 diagram corresponds to
the alveolar gas of these distal alveoli?
