Answer:
<em><u>is</u></em><em><u> </u></em><em><u>made</u></em><em><u> </u></em><em><u>of</u></em><em><u> </u></em><em><u>a</u></em><em><u> </u></em><em><u>double</u></em><em><u> </u></em><em><u>layer</u></em><em><u> </u></em><em><u>of</u></em><em><u> </u></em><em><u> </u></em><em><u>phospholipids</u></em>
In developed nations people have more fast food options which lead to cardiovascular disease. As well as screen time all day since this is one of the factors of cardiovascular disease. Undeveloped nations don't have fast-food or television to watch all day, since they play outside.
he answer is because <span>samples of air taken over erupting volcanoes shows that volcanoes
contribute a small amount of chlorine in the stratosphere compared to CFCs. Volcanic
eruptions account for a large instability of chlorine from land to the
atmosphere on a yearly basis. This is in addition to chlorine that enters the
atmosphere from sea spray, industrial processes and biological gases which are
from CFCs. All of these inputs happen near or at the base of the atmosphere. Very
little of the material emitted from volcanoes makes it up into the upper
reaches of our atmosphere which is the stratosphere where it could touch the
ozone layer. However, most of it is believed to be deposited lower down which
is in the troposphere, where it then rained out back to the surface of the
earth.</span>
Answer:
B
Explanation:
RNAi is a cellular mechanism for post-transcriptional gene silencing. After transcription of a gene into mRNA, small interfering RNA (siRNA) and microRNA (miRNA) can target the mRNA to form dsRNA. This mRNA then becomes a target of ribonucleases such as the Dicer that break it apart. These mRNA, therefore, do not reach the cytoplasm for translation by ribosomes. This mechanism is hence harnessed and manipulated by scientists to study genes by silencing them.