Surface area
That sign is just indicating micro
<span>Attached to each sugar ring is a </span>nucleotide base<span>, one of the four bases </span>Adenine<span> (A), </span>Guanine<span> (G), </span>Cytosine<span> (C), and </span>Thymine<span> (T). The first two (A, G) are examples of a </span>purine<span> which contains a six atom ring and five atom ring sharing two atoms. The second two (C, T) are examples of a </span>pyrimidine<span> which is composed of a single six atom ring. A </span>base pair<span> is one of the pairs A-T or C-G. Notice that each base pair consists of a purine and a pyrimidine. The nucleotides in a base pair are </span>complementary<span> which means their shape allows them to bond together with </span>hydrogen bonds<span>. The A-T pair forms two hydrogen bonds. The C-G pair forms three. The hydrogen bonding between complementary bases holds the two strands of DNA together. Hydrogen bonds are not chemical bonds. They can be easily disrupted. This permits the DNA strands to separate for </span>transcription<span> (copying DNA to RNA) and </span>replication<span> (copying DNA to DNA). In our simple model, the entire base pair structure is represented by the single blue rod. Various more elaborate models can be constructed to represent base pairs, including the one above which shows individual atoms and bonds.</span>
Siltstone and sandstone are both granular materials but they are distinguished by grain size. The Wentworth scale places silt particles between 0.0039 to 0.0625 mm. This is smaller than very fine grained sand.
Siltstone and Sandstone may have identical mineralogy. They are generally comprised of quartz, feldspar and rock fragments. Because siltstone is comprised of smaller grains, it has smaller pore throats, resulting in lower permeability and higher capillary pressures than in an equivalent porosity sandstone.
They determine the inherited traits of an organism.