Density is mass of object per unit volume
Answer:
Determining a substance's physical or chemical identity. What are the two main requirements for identification? The adoption of testing procedures that give characteristic results for specific standard materials and the number and type of tests needed to identify a substance to exclude all other substances.
Answer:
<em>Atomic hydrogen efficiently scatters ultraviolet radiation emitted by the Sun, and the amount of scattered light sensitively depends on the amount of H atoms that are present in the atmosphere.</em>
Pili connects a bacterium to another of its species, or to another bacterium of a different species. That builds a bridge between the interior cells.This enables the transfer of plasmids between the bacteria
Answer and Explanation:
Cyclins and cyclin-dependent protein kinases (CDPKs, cell proteins) also function to control the cell cycle. A group of cyclins: the G1 cyclins, are synthesized during G1 phase and function to activate CDPKs which initiate DNA synthesis at the G1/S checkpoint. The cell fails to progress to S phase if there is no sufficient synthesis of G1 cyclins. After a cell passes through this point, the G1 cyclins are degraded, allowing for another group of cyclins: the M cyclins (mitotic cyclins) to be synthesized. M cyclins activate a second group of CDPKs which allow the cell to pass the G2/M control point and into mitosis.
In the G1/s check point, entrance into the S phase is blocked if the genome is damaged. In the G2/M check point, entrance into the M phase is halted if the DNA replication is incomplete. In the M phase, anaphase blocked if chromatids are not properly assembled.
