Answer:
The mice died
Explanation:
In Griffith's experiment, two strains of the same bacteria were used. S strain was smooth because it had a polysaccharide coat. This coat also made it virulent because mouse immune system was not able to destroy it and ultimately the mice died. R strain was rough because it did not have the coat and thus was harmless to mice.
When Griffith injected mice with dead S bacteria and living R bacteria together, the mice died. Live R bacteria had taken up the genetic material or as Griffith called "transforming principle" from the dead S bacteria and transformed into S bacteria. So live S bacteria were present again and they killed the mice.
Answer:
Species separated by a physical barrier for a long time, suffer allopatric speciation, so they can not interbreed anymore.
Explanation:
Allopatric speciation consists of the geographic separation of a continuous genetic background giving place to two or more new geographically isolated populations. These separations might be due to migration, extinction of geographically intermediate populations, or geological events. In this speciation, some barriers impede genetic interchange, or genetic flow, as the two new populations that are separated can not get together and mate anymore. These barriers might be geographical or ecological.
Vicariance is the geographical separation of an original population into two or more new groups. Discontinuities in the physical environment like rivers, mountains, water, etc., are physical barriers that impede genetic flow between the separated groups.
The process of allopatric speciation involves different steps:
- The emergence of the barrier.
- Interruption in the genetic interchange
- The occurrence of new mutations and their accumulation in time in each population. Slow and gradual differentiation.
- Genetic divergence by natural selection and reproductive isolation makes it impossible for the two groups to mate even if the barrier disappears.
- Prezigotic isolation mechanisms favored by selection once occurs a secondary contact between the new species in formation.
Answer:
Explanation:
True cause pesticide can end up killing other bugs you don't wanna kill like bees
