I think it is D. The National Institutes of Health found it effective in reducing pain and other symptoms, but it is not clear how it works.
Jet airplanes take up a lot of fuel and money. Not only are they burning fossil fuels quickly, but they're also being flown on a basis. Planes are sent out constantly, and the amount of carbon it releases into the atmosphere is incredibly dangerous.
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: a) true
Explanation:
The goal of mitosis is to produce daughter cells that are genetically identical to the mother cell, without a single extra or missing chromosome. Meiosis, on the other hand, is only used for one purpose in the human body: the production of gametes or sex cells, i.e. sperm and eggs. The question is oriented to mitosis, <u>in which prior to this cell division, the cell duplicates its DNA</u> so that each daughter cell then inherits the genetic material. That is, the cell originally possesses 23 chromosomes, they duplicate to a total of 46 so that then each daughter cell receives 23.
The metaphase is the second phase of mitosis and meiosis that occurs after prophase where the envelope is lost and microtubules of the achromatic spindle (also called meiotic or mitotic) appear.
During metaphase, the chromosomes align themselves in the middle of the cell and this balanced midline spindle alignment is due to the equal and opposing forces generated by the kinetochore brothers.
Then during metaphase, the chromosomes will line up in the center of the cell to be separated and go each to a different daughter cell. But the moment they're found there, each orientation of chromosomes produces gametes with the same genetic information from each parent. <u>Because because there have been no changes or mutations in the chromosomes, they have duplicated and have the same genetic information.</u>
