Answer:
NO. Mitosis involves one set of nuclear division and results in two nuclei that are exactly the same as the original. On the other hand, meiosis involves two sets of nuclear divisions.
Explanation:
Mitosis is a type of cell division normally occurring at the sites of growth and development of new tissues and also at sites of repair. It also occurs during asexual reproduction of organisms. Each mitotic cell division is a process that follows distinct phases.
Each mitotic division results in the formation of two daughter cells which are genetically identical to the parent cell, that is they have the same number and type of chromosomes as the parent cell.
During telophase, a nucleolus develops in the nucleus of each daughter cell. The cytoplasm divides in the process called cytokinesis. An invagination develops and finally splits the cell into two daughter cell each with its own nucleus and cytoplasm.
Answer:
There are many points at which eukaryotic gene expression can be controlled, through pretranscriptional control, transcriptional control, and posttranscriptional control
Explanation:
The pretranscriptional control determines the accessibility of chromatin to the transcription machinery. It is affected by supercoiling and methylation. It is also known as epigenetic regulation, and it does not depend on the sequence but on the conformation of the DNA.
While transcriptional control determines the frequency and / or speed of transcription initiation through the accessibility of the start sites, the availability of transcription factors and the effectiveness of promoters.
The post-transcriptional control is the one that is exercised once the transcript has finished synthesizing. It can be of several types:
• Maturation control: As the RNA adjustment can be made.
• Transport control: Most RNA has to go out to the cytoplasm to perform its function. For this they have to cross the pores of the nuclear membrane, where you can select the RNAs that will be transported and those that will not.
• Stability control: The half-life of RNA can be regulated by the expression of RNAs or mRNA stabilizing proteins in the cytoplasm.
• Translational control: It is exercised on the frequency with which the mRNAs begin to be translated. It can also affect the frequency with which proteins mature and the availability of enzymatic effectors.
Answer:
Explanation:
A fall in temperature can also adversely affect cell and cell membranes. At low temperatures, the phospholipids' fatty acid tails are moving less and stiffer. This reduces the membrane's overall fluidity as well as reduces its permeability and perhaps limits the entry into the cells of vital chemicals like oxygen and glucose. Also, low temperatures can impede cell development by preventing cell size expansion.
In severe cases, such long term exposure to sub-freezing temperatures, fluid in the cell can start solidifying and can form crystals that breach the membrane and destroy the cell.
In my opinion it is diluted and formed into concentrate and is then divided into proportion.
