#Question id: 5232
#Unit 11. Evolution and Behavior
Using molecular clock, it was estimated that two species X and Y must have diverged from their common ancestor about 5 x 10^6 years ago. If the rate of divergence per base pair is estimated to be 0.06 per million years, what is the proportion of base pairs that differ between the two species now?
#Question id: 2073
#Unit 2. Cellular Organization
The phosphate transport system in bacteria imports phosphate into the cell even when the concentration of phosphate outside the cell is much lower than the cytoplasmic phosphate concentration. Phosphate import depends on a pH gradient across the membrane—more acidic outside the cell than inside the cell. In this bacterial cell, phosphate transport is an example of:
#Question id: 13552
#Unit 6. System Physiology – Plant
#Question id: 11150
#Unit 7. System Physiology – Animal
Use the information in the table to answer the question.
Calculate the equilibrium potential for potassium. Assume a temperature of 37°C.
#Question id: 7236
#Unit 5. Developmental Biology
Which of the following statement justified that the PMZ in chick is
functionally equivalent to the amphibian Nieuwkoop center?
A.
The posterior marginal zone produces Wnt8c and that, the PMZ cells secrete Vg1,
a member of the TGF-β family.
B.
PMZ cells capable of inducing the accumulation of β-catenin
C.
PMZ cells secretes BMP, a member of the TGF-β family.
D.
PMZ secretes its own Nodal antagonist—the Lefty protein.
Which of the following combination is correct?