RNA
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RNA is genetic material for some viruses and it is required to allow protein synthesis to occur in the cell.
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RNA is also considered to be the original nucleic acid
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STRUCTURE:
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RNA is a single strand made up of a ribose sugar and phosphate backbone and the nitrogen bases adenine, guanine uracil and cytosine.
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Has a single helix shape
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RNA is a copy of DNA made during transcription.
Types of RNA
RIBOSOMAL RNA- rRNA
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rRNA molecule is a structural component of ribosomes as it aids in the creation of ribosomes.
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Also, rRNA serves as a genetic link between mRNA and tRNA in protein synthesis.
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85% to 90% OF rRNA CAN BE FOUND IN EACH CELL.
RNA Transcription Process
Step 1: DNA Unwinds
DNA unwinds and exposes a set of bases (a gene) along the template strand. The non-template or coding strand is not copied into a mRNA strand since it has almost the exact same sequence as the coding strand. Only differences are in DNA there is thymine and in mRNA there is uracil.
Step 2:
Complementary base Pairing
New nucleotides are brought to the site of transcription that then pair up with the bases on the template strand of DNA. However, uracil binds to adenine in the sequence and adenine binds to thymine. Due to this there is no thymine in the mRNA strand.
Step 3:
RNA Strand is Released
The RNA strand unbinds to the template strand of the DNA strand and leaves the nucleus through the nuclear pores since it is a very small molecule.
Step 4:
DNA Rewinds
After the RNA strand unbinds to the template strand of DNA the DNA strand rebinds to its coding strand and returns to its double helix shape. This entire process occurs in the nucleus in the dark-staining spots called nucleoli or nucleolus.
OVERVIEW OF PROCESS
