RNA’s structure and the Birth of the RNA triplets - PowerPoint PPT Presentation

RNA’s structure and the Birth of the RNA triplets

Mrs. New-New

• Has a single strand made up of many nucleotides
• There are 3 types
• mRNA
• tRNA
• rRNA

Purines- 2 rings

• Adenine
• Guanine

Pyrimidines- 1 ring

• Cytosine
• Uracil (replace Thymine)

• Born during transcription in the nucleus
• Her father is DNA (Big Daddy)
• She is the most important of the RNA triplet
• DNA gave her the blueprint needed to make proteins
• Once she has the blueprint needed to make proteins she is going to leave DNA in the nucleus and travel to a ribosome
• 3 nitrogen bases on her = 1 codon

• Born during transcription in the nucleus
• His father is DNA (Big Daddy)
• He is going to help mRNA (Lil Momma) in her mission to make proteins by dropping off amino acids
• He is also going to leave the nucleus and travel to a ribosome.
• 3 nitrogen bases on him= 1 anticodon

• Born during transcription in the nucleus
• Its father is DNA (Big Daddy)
• It will also leave the nucleus and combine with a ribosome
• This is the place where mRNA and tRNA will meet to “translate” and make proteins

• DNA must be copied to messenger RNA (mRNA)
• mRNA goes from nucleus to the ribosomes in cytoplasm
• mRNA complements known as codons
• One codon is 3 nitrogen bases long
• Remember RNA has uracil (U) instead of thymine (T)!

• DNA is unzipped by the enzyme RNA Polymerase at the promoter region.
• RNA Polymerase will then drop off complementary RNA nucleotides to Big Daddy’s exposed bases ononeside. (She is making mRNA=Lil’ Momma, however all three triplets are being made.
• She will stop dropping off nucleotides when she comes to the termination signal.

4. Lil” Momma now has the blueprint to make proteins and is ready to leave the nucleus; but before she can leave, she has to be edited. (Introns are taken out and Exons are put back together)

5. mRNA, tRNA, and rRNAwill now leave the nucleus and travel to a ribosome.

6. DNA zips back up.

- This happens in the nucleus, right after DNA replication

A C G T A T C G C G T A

T G C A T A G C G C A T

DNA unzips

*DNA will serve as the template

A C G T A T C G C G T A

U G C A U A G C G C A U

Template DNA is Matched Up with Complementary RNA Nucleotides

A C G U A U C G C G U A

U G C A U A G C G C A U

mRNA leaves nucleus and goes to ribosomes

A new complementary RNA strand is made (rRNA)

A C G T A T C G C G T A

T G C A T A G C G C A T

DNA zips back up

• The template strand is the DNA strand being copied
• The rRNA strand is the same as the DNA strand except Us have replaced Ts

Translation Notes

It’s Newson baby!!

A C G T A T C G C G T A G C T C A A G G T

A C G T A T C G C G T A G C T C A A G G T

C G A U A U C G A G U A U C U C A A U G U

• How many codons are on this strand of mRNA?
• 7

• 3-nitrogen base code is called an “anticodon”
• tRNA has an anticodon attached to one end and an amino acid attached to the other

• The genetic code found mRNA is “translated” into proteins
• The codons on mRNA are what’s important. They specify or code for specific amino acids.
• Codon code is specific!
• 20 amino acids
• 64 codon combinations

• rRNA (Ramada Inn) combines with protein to become apart of the ribosome. mRNA and tRNA will arrive at this ribosome.
• mRNA (Lil Momma) contains codons (eggs) that are complementary to tRNA’s (Tyrone) anticodons (sperm).
• tRNA will match it’s anticodon to mRNA’s codon and every time that happens tRNA will leave behind an amino acid.

4. However, tRNA can’t start matching its anticodon and dropping off amino acids until it comes to the start codon (AUG). Now once it sees the start codon, it’s on!!!!

5. tRNA will keep matching it’s anticodon with mRNA’s codon and leaving behind amino acids until it comes to one of the stop codons. (UAG, UGA, UAA)

6. Once tRNA comes to a stop codon, it will stop translating mRNA and the long chain of amino acids will break off and become a protein (polypeptide).

1. DNA replication – DNA makes a copy of itself

• Where: Nucleus When: S phase of Interphase

2. Transcription- DNA produces the RNA triplets and gives the blueprint to make proteins to mRNA

• Where: Nucleus When: Right after DNA Replication

3. Translation – mRNA and tRNA work together with rRNA to combine amino acids to make proteins

• Where: Ribosome When: Right after Transcription