<span>Baroreceptors are special receptors that detect changes in your blood pressure. Important baroreceptors are found in the aorta and the carotid sinus. If the blood pressure within the aorta or carotid sinus increases, the walls of the arteries stretch and stimulate increased activity within the baroreceptors.</span>
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:
<span>Calcium because it is responsible for making our bones strong, thus allowing us to perform many activities.
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Industrial pollution is density-independent
habitat is density-dependent
food is also density-dependent because its availability varies depending on this factor
a hurricane is abiotic and density-independent
number of mates is density-dependent and hunting by humans is density-independent
<span>Cells control cell division in order to maintain normal cell function. If something happens to the control of the cell division, the healthy cells will divide uncontrollably. These new cells are cancer cells. </span>
The mutations in three genes are responsible for development of cancers:
1. Mutation in proto-oncogenes. Proto-oncogenes normally signal cells to grow and differentiate. Proto-oncogenes can become oncogenes due to mutations which result in the uncontrollable division of the cells.
2. Mutation in tumor suppressor genes. In normal cells, tumor suppressor genes suppress genes essential for cell cycle and that way they prevent uncontrollable cell division. However, after a mutation in these genes, suppression is lost and the cell may progress to cancer.
3. Mutation in stability genes. In normal cells, they have no role either in cell death or growth, but they control mutation rate. Mutation in stability genes results in situation where all genes, including proto-oncogenes and tumor suppression genes, are more frequently mutated.
