A culture of E. coli is grown on minimal medium plates supplemented with either tryptophan, histidine, or lysine. The resulting colonies are replica plated to three minimal medium plates containing no supplements. The next day, colonies grow on the minimal medium replica plated from the histidine and lysine plates, but colonies do not grow on the tryptophan replica plate. This indicates that the E. coli strain is a

histidine auxotroph.

tryptophan auxotroph.

histidine and lysine auxotroph.

prototroph.

the answer for apex is "1 and 6"

is this for the e2020 class

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.

ecological efficiency: % of usable energy transferred as

biomass from one trophic level to the next typical is 10% efficient (90% of

energy is lost),is diagramed as the pyramid of energy flow. then osprey eagle

are tertiary consumer and the shrimp are primary consumer, so to balance

mass of shrimp (1/0.1) / 0.1 = 100 kg