Answer:
False
Explanation:
The histones that are more positively charged, tight hardly to negatively charged DNA. So, enzymes, such as acetyltransferases, that reduce the positive charge of histones promote transcription.
Chromatin structure and its modifications can change the package of the DNA and consequently, alter the gene expression. The most common modifications of the chromatin are covalent modifications such as acetylation/deacetylation (by acetyltransferases and eacetylases), methylation (by methyltransferases), and phosphorylation (by kinases). This is the way of gene expression regulation.
The effects of modifications are different, for example methylation promotes condensation of the chromatin and as a consequence, prevents binding of transcription factors to the DNA (transcription is repressed).
Acetylation loosens the association between nucleosomes and DNA (because it neutralizes the positive charge of histones) and consequently promotes transcription. Deacetylation is a process opposite to acetylation.
Answer:
c
Explanation:
when to objects come together and conform or conjoin they take what make the better of one from the 2 that are malleable
Feces are deposited on the ground, and the bacteria in the soil breaks it down, and uses the nutrients
Answer:
B. After clearcutting, plant uptake stopped and nitrogen accumulated in the soil.
Explanation: Clear cutting leaves the soil bare and allows for direct penetration of sunlight this increases the soil temperature which favors the activity of soil microrganism. This microrganism activity increase the production of ammonium and nitrate hence the increase in soil Nitrogen level. Clearcutting then allows for accumulation of Nitrogen produce due to removal of plant or forest tree that could use up the Nitrogen produced.
Answer:
Totipotential.
Explanation:
There are different cell potencies. A <u>totipotent</u> cell is a stem cell that can divide itself and <u>differentiate in any cell </u>that the organism needs. That is to say, endodermal cells, ectodermal cells, mesodermal cells, or extra-embryonic tissues. As cells differentiate themselves, they can gradually lose their potential. The cell's category that follows is pluripotent cells. These are stem cells that can only differentiate into ectoderm cells, endoderm cells, or mesoderm cells. Then we have multipotent cells, which differentiate into tissue cells. The next category is oligopotent cells. They give a limited number of specific cells, and lastly unipotent cells, only differentiate in one type of cell.
