Nitrogen fixation is a process in which nitrogen (N2) in the Earth's atmosphere is converted into ammonia (NH3). Atmospheric nitrogen or molecular dinitrogen (N2) is relatively inert: it does not easily react with other chemicals to form new compounds.
Fertile soil is valuable because there is a limited supply. Less than one eighth of land on Earth has soil that are well suited for farming.
The thick, fertile soil of the prairies took many thousands of years to develop.
The two ways that the value of soil can be reduced is help use soil correctly, peanuts were once a corp to help soil, and still can be. The soil value recycle rocks and bedrock.
The value of soil is reduced when it loses its fertility and when topsoil is lost due to erosion. Soil can be conserved through contour plowing, conservation plowing and crop rotation. The thick mass of tough roots at the surface of the soil.
The chemical substance in adult male pig's urine, which can also be found in other mammals, is called Puberty Accelerating Pheromone. It is also found in boar's saliva, and was said to be responsible in inducing early puberty in young female piglets.
Histone deacetylase is responsible for removing the acetyl group from the histone 3 lysine 9 residue. Remember that deacetylation is one step in converting euchromatin to heterochromatin. Because euchromatin is transcriptionally active (transcriptional machinery is able to reach gene of interest), and blocking histone deacetylase activity would result in an the DNA remaining as euchromatin, we would expect to see an increase in transcriptional activity.
So there’s your answer: An increase in transcriptional activity.
In certain organisms, like humans, there are two morphologically distinct types of gametes: (1) the male gamete (i.e. sperm cell) and (2) the female gamete (i.e. ovum). The male gamete is smaller in size and motile whereas the female gamete is several times bigger and non-motile. The haploid condition of the two gametes is essential so that at fertilization during sexual reproduction the integrity of the chromosomal number is maintained throughout generations.
Hope this helps.