Scissors Glue Something to write with Please turn in your homework Protein Synthesis Consists of 2 main steps Step 1 Transcription Step 2 Translation DNA Central Dogma Proteins RNA Occurs in the Nucleus ID: 918977
Download Presentation The PPT/PDF document "Today you will need: Your science notebo..." is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Today you will need:
Your science notebookScissorsGlueSomething to write with
Please turn in your homework
Slide2Protein Synthesis
Consists of 2 main steps
Step 1: Transcription
Step 2: Translation
Slide3DNA
Central Dogma
Proteins
RNA
Occurs in the Nucleus
Translation
Occurs at the Ribosome
Transcription
Step 1
Step 2
Slide4DNA
RNA
Occurs in the Nucleus
Transcription
Step 1
Slide5What is RNA?
RNA is different from DNA in 3 ways
Slide6The sugar is
Ribose instead of deoxyribose
Slide7RNA is
Single stranded instead of double stranded
Slide8Thymine is replaced by
Uracil
Adenine
Uracil
In RNA
There is no Thymine
Adanine
bonds to
Uracil
A – U How to code DNA into mRNA
CGAUG
C
T
A
Let’s make an RNA strand
DNA
A
T
G
C
A
C
mRNA
U
A
G
G
C
U
Slide9Types of RNAMessenger
RNA (mRNA)Carry copies of instructions for the assembly of amino acids into proteinsServe as “messengers” from DNA to the rest of the cellRibosomal RNA (rRNA)Helps build ribosomesTransfer RNA (tRNA)Transfers the amino acid to the ribosome
There are 3 types of RNA
:
C10L10C12
Slide10Step 2
of protein synthesisTRANSLATION
Slide11Slide12During translation, the nitrogen bases of mRNA tell the cell which amino acids (building blocks of proteins) are needed to build a protein (polypeptide).
Slide13mRNA bases are read in groups of
3 called codons. Each codon codes for an amino acid.
Example:
RNA Strand: U C G C A C G
G
U
Reads as: UCG – CAC – GGU (3 codons)
Represents the amino acids:
Serine –
Histidine – Glycine
Slide14amINO
aCIDSThere are only 20 different amino acids, but
64
different codon possibilities, so several codons might represent
1
amino acid.
example:
UCU
,
UCC, UCA, and UCG all code for the amino acidSERINEThere is also one codon AUG that is called the START
codon because it starts protein synthesis.There are 3 stop codons that stop protein synthesis.
Slide15Lets practice
mRNA
AUG
UGA
CCU
Amino Acid
mRNA
GCG
GAU
UGC
Amino Acid
Second Base of Codon
First Base of Codon
U
C
A
G
Third Base of Codon
U
UUU
Phenylalanine
phe
UCU
Serine
ser
UAU
Tyrosine
tyr
UGU
Cysteine
cys
U
UUC
UCC
UAC
UGC
C
UUA
Leucine
leu
UCA
UAA
STOP
UGA
STOP
A
UUG
UCG
UAG
UGG
Tryptophan
trp
G
C
CUU
Leucine
leu
CCU
Proline
pro
CAU
Histadine
his
CGU
Arginine
arg
U
CUC
CCC
CAC
CGC
C
CUA
CCA
CAA
Glutamine
gln
CGA
A
CUG
CCG
CAG
CGG
G
A
AUU
Isoleucine
ile
ACU
Threonine
thr
AAU
Asparagine
asn
AGU
Serine
ser
U
AUC
ACC
AAC
AGC
C
AUA
ACA
AAA
Lysine
lys
AGA
Arginine
argAAUGMethionineMet (start)ACGAAGAGGGGGUUValinevalGCUAlaninealaGAUAspartic AcidaspGGUGlycineglyUGUCGCCGACGGCCGUAGCAGAAGlutamic AcidgluGGAAGUGGCGGAGGGGG
C10L10C12
AUG
START
Methionine
Slide17Lets practice
C10L10C12mRNA
AUG
UGA
CCU
Amino Acid
mRNA
GCG
GAU
UGC
Amino Acid
Met
(Start)
Stop
Pro
Cys
Asp
Ala
Slide18Translation
During translation the mRNA strand synthesized during transcription will be used to make a protein.
Slide19How is a protein (polypeptide) made?
The mRNA leaves the nucleus and attaches to a
ribosome
C10L10C12
Slide20Translation begins at the
START codon (AUG) on the mRNA.
The codons in mRNA match
anticodons
in
tRNA
.
TRNA transfers amino acids to the ribosome when they are called for by the codons in mRNA.
C10L10C12
How is a protein (polypeptide) made?
Slide21The ribosome moves down the mRNA strand, codon by codon, and each
tRNA brings an amino acid that is added to the growing protein (polypeptide).
C10L10C12
How is a protein (polypeptide) made?
Slide22C10L10C12