Explain how the meselson-stahl experiment with "heavy" nitrogen showed that dna replication is semiconservative.

1. Bacteria where grow in a medium composed of heavy nitrogen. After several generations the bacteria DNA was composed of heavy nitrogen (heavy nitrogen is an isotope of nitrogen).  

2. After several generations had passed, the bacteria were transferred to a nitrogen light medium.

3. As soon as the bacteria were transferred the bacteria DNA was isolated after the first and second generation through centrifugation.

4. Results: after 2 generations half of the DNA was intermediate and half was light; there was not heavy-only DNA.  The conclusion was that the new DNA is formed by an "old" strand and a "new" strand producing an intermediate weight.

answer: grassland biomes are closer to the equator and receive more rain.

grasslands are biomes that are dominated by grasses rather shrubs and trees. savanna are biomes that exhibit grasses, shrubs and small tree as vegetation. grasslands are located near the equator of the earth. these are found in north america. savanna biomes are found in africa, south america, australia and india. grassland exhibit moderate climatic conditions, it receives   amount of rainfall higher than savanna.   therefore, savanna exhibit dry and hot climatic conditions.