myoglobin
When DNA copies….. It copy's in a very specific order. It copies 5’-3’ from a 3’-5’ Template.
That means the DNA strand is in the following order… DNA
That means the DNA strand is in the following order…
Double Helix
Nucleotides: basic molecule of DNA Pyrimidine
Nucleotides: basic molecule of DNA Purine
Pyrimidines and Purines Made up of a 1.Sugar (5 carbon) 2.Phosphate group 3.Nitric Base
DNA Replication mlhttp:// ml
Differences between RNA and DNA RNA has only a SINGLE Strand (DNA is Double Stranded) RNA contains ribose instead of deoxyribose RNA polymerase can start the RNA transcription without a primer
Differences between RNA and DNA RNA uses Uracil(U) instead of Thymine(T) More errors occur in an RNA copy than in DNA copy of nucleotides (10 3 more than in DNA) FACT: DNA has a transcription error approximately every 10 7 nucleotides. RNA has an error approximately every 10 4 !
Differences between RNA and DNA WHY are there more errors in RNA Transcription? One of several reasons is that in rare instances Uracil can also bond with Guanine
Is this a Bad thing? WHY are there more errors in RNA Transcription? One of several reasons is that in rare instance Uracil can also bond with Guanine RNA is a temporary copy in Eukaryotes
Types of RNA mRNA= messenger RNA codes for a protein
Types of RNA tRNA= transfer RNA central to protein synthesis as adaptors between mRNA and amino acids
Types of RNA rRNA= ribosomal RNA form the basic structure of the ribosome and catalyze protein synthesis
Transcription- the synthesis of RNA under DNA (occurs in the nucleus) Translation- the actual synthesis of a polypeptide coded for by the mRNA. (changing the base sequence of the mRNA molecule into a chain of amino acids that form a polypeptide. For our purposes a protein.)
An mRNA copy is made from DNA in the Nucleus
The DNA strand from which the mRNA is copied is the TEMPLATE STRAND
The mRNA leaves the nucleus and enters a ribosome (made up of rRNA)
tRNA collects a specific amino acids present in the cell and brings it to the ribosome
The anticodon of the tRNA matches up with its counterpart codon on the mRNA
When the mRNA & the tRNA link up the amino acid detaches and is connected to the adjacent amino acid
This chain of amino acids is a protein (polypeptide)
rRNA Ribosome
rRNA mRNA enters the “A” site of the ribosome
rRNA When the first codon reaches the “P” site the tRNA brings down the amino acid and links up with the mRNA
rRNA The “E” site is where the amino acid separates form the tRNA and links up to adjacent amino acids. This is where the MRNA and tRNA leave the ribosome
ANTICODONS Anticodon Anticodons specify which amino acid a tRNA collects The anticodon then pairs up with its corresponding codon
ANTICODONS Anticodon So for example... The anticodon AGU would pair with the codon UCA. THEY ARE OPPOSITES OF EACH OTHER
So What's a codon? Codon This basic unit of genetic code is 3 nucleotides long It specifies a specific amino acid Each codon only specifies 1 amino acid (BUT…an amino acid may have several different codons that code for it)
THE END