1. From DNA to Proteins Chapter 13 DNA makes ____ makes ________.
Proteins are the links between ___________ and ________________.

2. ___________ and ___________ are the two main processes linking gene to protein
The bridge between DNA and ________ synthesis is RNA.
RNA differs from DNA
1. RNA contains _____as its sugar (not deoxyribose)
2. _______ replaces thymine.
AGTCAT becomes AGUCAU
3. An RNA molecule almost always consists of a _______strand.
Fig. 6.8a
This is an H in DNA

3. 4 types of RNA ________ - carries info for protein production
_______-transport amino acids in translation
_______- part of ribosome, has role in translation
________ - splicing mRNA

4. Chromosome- 1.5 x 108 base pairs containing about 3000 genes
0.4% of a chromosome, containing 10 genes
= 1. ________________
= 2. ________________ F
ATG B C D E
TAA 5’ 3’
DNA 3’ 5’ +1
AATAAA
3. _____________
AUG
Pre-mRNA
4._________
UAA
5. ______
6. ____________ E A B C D F
7mG
AAAAAA…..
UAA
AUG
7. ________________
Protein
NH2
COO-

5. ____________ - DNA is the template for RNA, usually __________ RNA (mRNA).
____________________ - the information contained in the order of nucleotides in mRNA is used to determine the __________ sequence of a polypeptide.
-Translation occurs at ____________.
Fig. 17.2a
The basic mechanics of transcription and translation are ________ in eukaryotes and prokaryotes.

6. In the genetic code, nucleotide triplets specify amino acids
In the __________, three consecutive bases specify an amino acid, creating 43 (64) possible ________.
The genetic instructions for a polypeptide chain are written in DNA as a series of three- __________words.

7. Know how to read this chart!!
The genetic code
Know how to read this chart!!
1. ___ of 64 triplets code for amino acids.
AUG codes for the methionine and ____ of translation.
Three codons –___, ___ and ____ do not code amino acids but signal the termination of translation.
2. The genetic code is __________but not_ _________ .
Typically several different codons specify a given amino acid
Any one codon indicates _ __________ amino acid.
Fig. 17.4

8. Know how to read this chart!!
The genetic code (cont.)
Know how to read this chart!!
A ______________ is established at the translation start 3’
RNA 5’
UUACGAUGGAUUCAAACGUCAGGGCCUAAGGCUAG
Met
Asp
Ser
Asn
Val
Arg
Ala
Stop codon
Start codon
Summary- The genetic code uses_ ____________________, or codons, each of which is translated into a specific amino acid.

9. The genetic code is nearly ______________ , from bacteria to mammals
Thus, we can synthesize bacterial proteins in ______________
Exceptions do exist- they use slightly altered genetic codes:
1.single-celled eukaryotes like
Paramecium.
2. certain mitochondria and chloroplast ____________

10. What actually makes the RNA?
Messenger RNA is transcribed from the template strand of a gene by ________________.
__________________________ :
separates the DNA strands
bonds the RNA nucleotides as they base-pair along the DNA template.
RNA 5’ 3’
DNA 3’ 5’

11. What marks the start of transcription??
Answer- Specific sequences of nucleotides called the _________ mark where gene transcription begins
In prokaryotes, RNA polymerase can recognize and bind ______________ to the promotor region.
In eukaryotes, proteins called ___________ first bind the promotor region, especially a __________ , then RNA polymerase II binds

12. Transcript Modification
unit of transcription in a DNA strand 3’
exon
intron
exon
intron
exon 5’
transcription into pre-mRNA
poly-A
tail
cap 5’ 3’
snipped out
snipped out 5’ 3’
mature mRNA transcript

13. Overview of eukaryotic transcription/translation
Chromosome- 1.5 x 108 base pairs containing about 3000 genes
0.4% of a chromosome, containing 10 genes
ATG
DNA C B E D F
TAA
= exon
= intron 5’ 3’
Template strand +1
AAUAAA
Regulatory DNA sequences
Transport to cytoplasm
UAA
AUG
hnRNA
Transcription
AUG
AAAAAA….. D
RNA Splicing
polyA tail,cap C A B E
7mG
mRNA
UAA F
NH2
COO-
Protein
Translation

14. How do proteins read the RNA molecule??
Answer-the ___________________
tRNA
_____________ (tRNA) - transfers amino acids from the cytoplasm’s pool to a ________________.
The ribosome adds each amino acid carried by tRNA to the growing end of the _________________ chain.
ribosome

15. A tRNA molecule Is about ___ nucleotides long
Contains attachment site for an amino acid.
Contains a loop with the ___________
Fig 3’ 5’
The anticodon base-pairs with a complementary codon on mRNA.
If the codon on mRNA is UUU, a tRNA with a
______ anticodon and a tRNA carrying phenylalanine will bind to it.

16. Translation
Translation can be divided into three ______ initiation 2. _________
3. termination
1. Initiation
Small ribosomal subunit binds mRNA
Initiator tRNA (with methionine) is attached to start codon
Fig

17. 2. Elongation - Amino acid sequentially added
Translation
c. Translocation - the ribosome moves the tRNA with the attached polypeptide from the A site to the P site.

18. 3. Termination occurs when ribosome reaches a _____codon.
Translation
3. Termination occurs when ribosome reaches a _____codon.
A ____________ binds to the stop codon and hydrolyzes the bond between the polypeptide and its tRNA in the P site.
Fig
Other translation facts
Multiple ribosomes, polyribosomes, may trail along the same _______.
A ribosome requires less than a ________ to translate an average-sized mRNA into a polypeptide.
Fig

19. Overview Transcription Translation mRNA rRNA tRNA
Mature mRNA transcripts
ribosomal subunits
mature tRNA
Translation

20. Point mutations can affect protein structure and function
__________ are changes in the genetic material of a cell (or virus).
include large-scale mutations in which _____ segments of DNA are affected (translocations, duplications, and inversions).
A chemical change in just one base pair of a gene causes a _______________
In sickle cell, a single T to A mutation changes amino acid from glu to val
_________ - alterations of nucleotides still indicate the same amino acids because of redundancy in the genetic code.
Many other mutations cause no effect in function

21. Other base-pair substitutions cause a readily detectable change in a protein.
_______ mutations are those that still code for an amino acid but change the indicated amino acid.
_______ mutations change an amino acid codon into a _____ codon, nearly always leading to a nonfunctional protein.
Fig

22. Insertions and ______ are additions or losses of nucleotide pairs in a gene.
These have a _________ effect on the resulting protein more often than substitutions do.
Unless these mutations occur in multiples of ____, they cause a ________ mutation.
All the nucleotides downstream of the deletion or insertion will be improperly grouped into codons.
The result will be extensive missense, ending sooner or later in nonsense - premature termination.
Fig

23. ______________Mutation
Really bad!!
mRNA
PARENTAL DNA
amino acid sequence
ARGININE
GLYCINE
TYROSINE
TRYPTOPHAN
ASPARAGINE
altered mRNA
BASE INSERTION
altered amino acid sequence
ARGININE
GLYCINE
LEUCINE
LEUCINE
GLUTAMATE

24. __________ mutagens may operate in several ways.
__________ are chemical or physical agents that interact with DNA to cause mutations.
________agents include high-energy radiation like X- rays and ultraviolet light.
__________ mutagens may operate in several ways.
As base ____________ that may be substituted into DNA, but that pair incorrectly during DNA replication.
Interfere with DNA replication by inserting into DNA and distorting the ______________.
Cause chemical changes in bases that change their pairing properties.

25. TRANSCRIPTION
Unwinding of gene regions of a DNA molecule
Pre mRNA Transcript Processing
mRNA
rRNA
tRNA
protein subunits
Mature mRNA transcripts
ribosomal subunits
mature tRNA
Convergence of RNAs
TRANSLATION
Cytoplasmic pools of amino acids, tRNAs, and ribosomal subunits
Synthesis of a polypetide chain at binding sites for mRNA and tRNA on the surface of an intact ribosome
FINAL PROTEIN
Fig , p. 210
Destined for use in cell or for trasport