Answer:
The miRNAs act as post-transcriptional silencers, as they are similar to specific mRNAs and regulate their stability and translation. They are small endogenous non-coding ribonucleic acid (RNA) molecules, with about 22 nucleotides, which act as regulators of gene expression in plants and animals, at the post-transcriptional level through the cleavage of a target messenger RNA (mRNA) or repression of translation.
In general, most miRNA genes are transcribed by RNA polymerase II in the nucleus in primary miRNAs (pri-miRNAs). Individually, a pri-miRNA can produce a single miRNA or contain groups of two or more miRNAs that are processed from a common primary transcript. These long pri-miRNA are cleaved by a complex comprising the double-stranded RNAse III enzyme (DROSHA) and its essential cofactor, the binding protein DGCR8 (DiGeorge Syndrome Critical Region 8 protein) in mammals. DROSHA contains two domains of RNAse III, each of which cleaves a strand of the RNA resulting in the precursor microRNA (pre-miRNA) with about 70 base pairs, which contains a double-stranded stretch and a single-stranded loop, forming a structure in clamp. The pre-miRNA is exported to the cytoplasm by the protein exportin-5 (XPO-5), where it is cleaved by DICER1, an RNAse III that assesses the 3 'and 5' ends of the pre-miRNA, generating a mature miRNA with about 22 nucleotides. The processing of pre-miRNA by Dicer promotes the unfolding of the RNA duplex in the form of a clamp. The position in the formation of the clamp can also influence the choice of tape.
Explanation:
Catabolism (a form of metabolism in which cells are breaking down larger units into smaller units).
Another answer is cellular respiration
They also need energy to move and to stay alive
The correct answer is: Induction, because this could be easily changed by changing the cell's environment.
Cell differentiation (process by which cell becomes specialized) can be under the influence of many factors:
• Cytoplasmic influence because cytoplasm can influence and control the behaviour of nuclear genes.
• Embryonic induction-changing the cell environment
For example: if cells from one region of the embryo are transplanted to some other region that transplant will most likely differentiate according to the chemical regulators of the surrounding cells.
• Proteins present in a cell influences its differentiation
• Cell-Cell interactions via cell-cell adhesion and signalling molecules.
