A) <u>Mutation</u> is the original source of variations for plants and other organisms which develops differences among their respective species
Explanation:
Genetic variation leads to the natural differences between each individual and among individuals of a species. The main cause for this variation is due to alleles that cause variations in the composition of genes or the DNA sequences.
A mutation is a genetic variation which leads to the creation of a new allele in a species population. Each variation in the DNA sequence leads to an allele formation and each allele leads to a difference in character or trait between individuals since they are the alternate version of the original genes.
Although genetic variations could be brought about by crossing over, random fertilization, or independent assortment; mutation is the original source because it provides the basic raw material for all the evolutionary changes.
<span>USGS is gathering information in the Arctic Ocean to study acidification and identify a baseline of information about the ocean's chemistry. This chemistry is expected to change due to decreases in the amount of summer sea ice.</span>
Differentiation in plants refers to the processes by which distinct cell types arise from precursor cells and become different from each other. Plants have about a dozen basic cell types that are required for everyday functioning and survival. Additional cell types are required for sexual reproduction. While the basic diversity of plant cell types is low compared to animals, these cells are strikingly different. For example, some cells such as parenchyma cells retain the potential to respond to environmental and/or hormonal signals throughout their life and, under the right conditions, can be transformed into another cell type (transdifferentiation). Other cells such as the water-conducting vessel elements undergo cell death as part of their differentiation pathway and thus can never transdifferentiate to another cell type
Read more: http://www.biologyreference.com/Co-Dn/Differentiation-in-Plants.html#ixzz54pAhWVdn
Answer:
After four half lives or 32 years, only 12.5 grams will be left.
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