Answer:A) Nitrogen
Explanation: nitrogen cycle ensures the movement of nutrients through the biosphere.it ensures that nitrogen is constantly reused and made available.
Nitrogen gas is available in the atmosphere but plants and animals cannot use it in that form.it must be converted to compounds such as ammonia or nitrate.
It is gotten from the atmosphere during rainfalls where it Is broken down and combines with oxygen to from nitrogen peroxide.
Nitrogen can also be fixated into ammonia by saprophytic bacteria.
Also when plants die their body tissues are broken down to form ammonia.ammonia can be oxidized into nitrates and nitrite which plants can use.
Nitrites can be released back into the atmosphere through denitrifying bacteria and the cycle continues.
Answer:
<u>Proto-oncogenes</u>
- These genes code for protein that normally promote cell division
- Mutations that increase activity of these genes may lead to cancer
<u>Tumor suppressor genes</u>
- These genes code for protein that normally prevent uncontrolled cell division
- Some products of these genes normally function in repairing damaged DNA
- Mutation that decrease activity of these genes may lead to cancer.
Explanation:
<em>Proto-oncogenes</em> are group of genes that ordinarily help cells develop. At the point when a proto-oncogene mutates or there are such a large number of duplicates of it, it turns into a "terrible" quality that can turn out to be forever turned on or activated when it shouldn't be. At the point when this occurs, the cell becomes wild, which can prompt malignant growth. This terrible quality is called an oncogene.
Tumor suppressor genes are normal gene that hinder cell division, fix DNA missteps, or tell cell when to undergo apoptosis (die). At the point when tumor suppressor gene don't work appropriately or inactivated, cells can develop uncontrollable growth, that ultimately lead to cancer.
Iron, oxygen and water react with the iron creating a substance known to us as rust.
Hope this helps.
