they are useful in agriculture because of their genetic diversity
Answer:
Intrusive igneous rocks crystallize below Earth's surface, and the slow cooling that occurs there allows large crystals to form.
Explanation:
intrusive igneous rocks are diorite, gabbro, granite, pegmatite, and periodontist. Extrusive igneous rocks erupt onto the surface, where they cool quickly to form small crystals.
true
Explanation:
messages from the nervous system cause these muscular contractions
Answer:
Acid , phenol or protein
Explanation:
The ratio of absorbance at 260 and 280nm is what is usually used to assess the purity which a DNA or RNA posses. A ratio of 1.8 is generally accepted as being pure for a DNA sample and a ratio of 2.0 is generally accepted also as being pure for RNA. when the ratio is significantly lower in each case, it indicates that there is presence of protein, phenol or other contaminants.