Researchers investigating the mechanism of vesicular transport assembled a cell-free system that included microtubule tracks, vesicles, and ATP. However, they observed no movement of transport of vesicles in this system. What were they missing?
a) an axon
b) contractile microfilaments
c) intermediate filaments
d) motor proteins

Other than earth, is also known to have magnetic pole reversal? a: venus b: mars c: earths moon d: the sun

Which set of terms best describes a community of miners who live out in the countryside of west virginia and use specialized geological equipment to analyze the composition of rock?

Define the apical impulse and describe its normal location, size, and duration. which abnormal conditions may affect the location of the apical impulse? explain the mechanism producing normal first and second heart sounds. describe the effect of respiration on the heart sounds. describe the characteristics of the first heart sound and its intensity at the apex of the heart and at the base. describe the characteristics of the second heart sound and its intensity at the apex of the heart and at the base.