Download Replication/Transcription/Translation

A PuhJayJay Presentation
Daily Catalyst
 1. If there are 34% of Adenines in DNA, what is the
percentage of uracil in RNA?
 34%
 2. Replicate the following segment of DNA:

5’- ATCGGCTACGTTCAC -3’
 3’ TAGCCGATGCAAGTG 5
 3. How does RNA polymerase know which nucleotides
to add?
 RNA Polymerase uses the rules of base pairing to add
the correction RNA nucleotides.
Class Business
You gon’ learn some sh*t!!
Replication
DNA is copied in the nucleus in
the process of replication.
Steps
 Step 1: DNA is unzipped at the 3’ end by helicase.
 Step 2: Once the DNA has been unzipped, the
enzyme DNA polymerase adds new nucleotides to
the 3’ end only!!!
 Step 3: DNA Ligase glues all of the DNA pieces
together.
 Step 4: DNA polymerase and DNA ligase
proofread the DNA and repair any mistakes
Transcription
 Transcription transfers genetic information
from DNA to RNA.
 Transcription occurs in the nucleus.
Steps of Transcription
 RNA polymerase binds to DNA at the
PROMOTER (TATA)
 RNA Polymerase adds RNA nucleotides to
the 3’ end.
 RNA Polymerase falls off the DNA at the
terminator.
 The RNA that is made in transcription is
called pre-mRNA.
Afterwards
 A poly (A) tail, consisting of adenine nucleotides is
added to the 3’ end.
 The 5’ end is capped off with a modified guanine
nucleotide forming a 5’ cap. The cap helps with
binding to the ribosome.
 snRNP’s and spliceosomes remove the introns and join the
exons together
Review Time
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Replication
1. Helicase unzips DNA
2. DNA Polymerase
adds DNA nucleotides
to the 3’ end
3. Ligase glues
segments together
4. DNA Poly and Ligase
proofread the DNA
Transcription
 1. Helicase unzips DNA
 2. RNA Polymerase
attaches to promoter
(TATA)
 3. RNA Poly adds RNA
nucleotides to the 3’ end
 4. RNA poly detaches
when it reaches the
terminator
Translation
 Translating the genetic information from DNA
into amino acids
 Translation occurs in the ribosomes.
 tRNA is the translator
Steps
 mRNA binds to the tRNA at the anticodon at the
ribosome.
 tRNA will read each codon of the mRNA
 Correct amino acids are added at the amino acid
attachment site on tRNA
 Amino acids are added until a stop codon is reached
 Stop codons are on mRNA
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UAA, UAG, and UGA
Stop codons do not code for proteins
Turn and Talk
 Turn to your neighbor and ask how their day is going.
 Noise Level: Class (2 minutes)
Video
 https://www.youtube.com/watch?v=Kzgnl5-8WAk
Practice Problems
 What type of RNA makes up the ribosomes?
 rRNA
 Where does translation start on the mRNA?
 On the start codon
 Where does mRNA bind to tRNA?\
 On the anticodon
 What is the purpose of translation?
 To translate the genetic information in mRNA to amino
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acids.
Which process does not include DNA; Translation,
replication or transcription?
Translation
What is effect of the start codon being destroyed?
Translation will not start.
If the mRNA codon is AUG, what is the proper anticodon?
UAC
Tell me what ya know!
 True or false: Translation is the process of assembling
amino acids.
 True
 True or false: Transcription beings at a promoter region and
continues until RNA polymerase reaches a stop codon.
 False, terminator
 True or false: In a eukaryotic cell, DNA carries the
information for protein synthesis from the nucleus to the
ribosome.
 False, mRNA
 True or false: The anticodon is located on the tRNA and will
complementary bind to the mRNA.
 True
1. Name the 3 essential enzymes for replication.
DNA helicase, polymerase, and ligase
2. Describe the semi-conservative model.
The parent strand acts at the model for the new daughter
strand so the bases know how to pair up with another
3. Why is this model important to
DNA?
This is important because we need to keep our DNA and
make an exact copy of our DNA to pass onto our children.
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