When the population is small or there is no gene flow
Answer:
Mice and rats make up approximately 95% of all laboratory animals, with mice the most commonly used animal in biomedical research.
All animals and plants are made of cells. Animal and Plant cells have features in common, such as a nucleus, cytoplasm, cell membrane, mitochondria and ribosomes.
In biology, a producer is something that MAKES food. Plants are producers. Then there are consumers, which eat producers (most animals are consumers). <span>Finally, there are decomposers, which break down producers and consumers into nutrients which producers can use to start the cycle over.
Hope that helped =)</span>
