D)crossing over of homologous chromosomes during meiosis.
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:
Answer:
Some animals have pouches to carry babies.
The babies are warm and are also protected from danger in their mother's pouch. Some animals have pouches to carry babies. Kangaroos are called marsupials because they have a special pouch for their babies.
Explanation:
I hope it helps you btw Can I get a brainliests please ☺️
Answer:
<em>Well, Cells of the immune system not only use lymphatic vessels to make their way and T cells mature in the thymus, they both initially develop from bone marrow. B cells are immune cells that function primarily by producing antibodies. structure on the surface of a pathogen that binds to T or B lymphocyte antigen receptors. Hope That Helps!</em>
<em>From Itsbrazts.</em>
Increasing the temperature might cause proteins within an enzyme to denature. This will cause the enzyme to stop working properly.
