sbi4u molecular genetics review explain the significance of this experiment

SBI4U Molecular Genetics Review

Explain the significance of this experiment


Griffith Experiment proved bacterial transformation occurred through a physical, heritable means: but, was it protein or DNA?

Still not conclusive…


Explain the significance of

this experiment


Hershey & Chase

Experiment

Demonstrates that it’s DNA, not protein,

passed on from one generation

to another:

35S not found in offspring virus

32P present in offspring virus

35S 32P


Another Look at the Hershey & Chase

Experiment


U. DNA Nucleotide

V. Phosphate

W.Adenine

X.Cytosine

Y. Gene Locus, DNA backbone

Z. Hydrogen bonds

U

V

W

X

Y

Z


Avery & MacLeod Experiment: If you damage DNA, you destroy heredity.


Match-up Question:1. Meselson & Stahl = C

2. Chargaff = G3. Meischer = E4. Franklin = A

5. Watson & Crick = H6. Hershey & Chase = F

7. Avery, MacLeod, McCarty = D8. Griffith = B


Identify the labeled structures:

A Amino Acid

B tRNA

C Anticodon

E mRNA

F Ribosome

G Polypeptide


Identify the labeled structures:

1 Lagging Strand2 Leading Strand

3 DNA pol.4 Ligase

5 RNA Primer6 Primase

7 Okazaki fragment

8 DNA pol.9 Helicase10 ssb’s

11 Gyrase


Review Booklet – 6.4 DNA Replication & RepairQ 1: Replication is more suitable because it conveys not

only the precision required, but also the semi-conservative nature of DNA synthesis: “half old, half new”

Q 3: Table 1 information:R.O: the starting point, at an RNA primer

H: Unzips DNA strandsR.F: point of DNA strand separationT: aka gyrase; untwists DNA helix

SSB: loosely bound to DNA strands, prevent reannealingR.B.: gap between two replication forks


Review Booklet – 6.4 continuedQ 4: Table information:

NT: provides bases for the nucleotidesPB: strong covalent bond of DNA backboneRNAp: builds a primer needed for DNApol

RNA primer: provides attachment pt for DNApolDNApolIII: extends the DNA chain

LdS: 5’ 3’ direction, continuous synthesisLgS: 3’ 5’ orientation, discontinuous syn.

OF: short DNA strands of Lagging strandDNApolI: aka RNAse H; removes primer

Ligase: joins Okazaki fragments


Review Booklet – 6.4 continuedQ 5: Table information:

Bp mismatch leads to a bulge or twist in the DNA double helix. The weakened point could lead to a gross chromosomal

mutation.DNA repair complex, involves DNApol II & I; able to ‘edit’ point

mutations in most cases by excising incorrect nucleotide, replacing w correct one.

Q 6: Diagram Labels:1. Helicase & Gyrase2. Replication Fork

3. SSb’s 4. Ligase 5. point of ligation6. DNA Polymerase III 7. Template strand

8. 9. Okazaki fragments 10. RNA primer 11. Primase

SBI4U Molecular Genetics ReviewReview Booklet – 7.2 Transcription & 7.3 Translation

Q 1: Table information:Promoter + TATA Box: site of RNA polymerase binding

RNA Polymerase: synthesis of new mRNA strand

Coding strand: DNA strand NOT being transcribed. 5’ 3’Template strand: 3’ 5’ strand of DNA that IS being

transcribed.*it must be this strand in order to ensure mRNA is made in

5’ 3’ direction

Start Codon: TAC triplet that indicates start point of transcription

Q 2: uh….. Transcription, perhaps? Give us some credit, textbook.

Q 1: tRNA is much shorter than mRNAQ 2: why yes, I do have a picture to show you!

SBI4U Molecular Genetics ReviewReview Booklet –7.3 Translation

Q 3: Anticodon sequences will be: CAA, CGG, UUU, GGA

Q 4: This is a property of the code called Code Redundancy. A limited set of bases in the ribonucleotides (A, C, G, U) can be rearranged into 61 codons (64, with the stop codons!) for the 20 amino acids. Proteins are

built out of a limited ‘alphabet’ of 20 amino acids by repetition and duplication of them, as needed.

Q 5: A Ribosome is made of two different parts, called the small and large ribosomal subunits. mRNA threads through a ribosome.

A tRNA molecule, with an amino acid attached to it and the anticodon that pairs with the amino acid’s mRNA codon,

introduces the amino acid to be added to the polypeptide chain next. The amino acid is added to the chain and the tRNA is

released. Other tRNA molecules add subsequent amino acids to the polypeptide.

And that, children, is the world’s lamest fill in the blanks paragraph. #aminoacid


Review Booklet – Chapter 7 summaryQ 5: Transcription diagram:

a. DNA b. RNA polymerase c. mRNA

Q 6: Translation diagram:a. Ribosome b. mRNAc. anticodons d. codon

e. Ribosomal large subunit, A sitef. P Site g. E site h. polypeptide

i. tRNA


Review Booklet – short answer questionsQ 1: DNA excision (cutting) by restriction enzymes, and

complementary pairingQ 2: Bacteria conjugate, Viruses transfer plasmids to

host cellsQ 5: Introduction of desirable traits into crop

plants or farm animalsQ 6: By creating transgenic bacteria to produce clotting factor much more quickly in a lab setting

Q 7: Paternity testing; criminal forensics; paleobiology; taxonomy; identification of missing persons, etc.


Review Booklet – short answer questionsQ 9 - 20: Matching Test

9B 10C 11E 12A 13B 14D15C 16B 17E 18B 19C 20B

Q 21: A Q 22: E Q 23: BQ 24: E Q 25: B Q 26: B Q 27: E


Review Booklet – short answer questionsQ 4-13: 4A 5B 6A 7B 8A 9B 10B 11B 12A 13B

Q14-21: 14B 15B* (really all of them!) 16A 17B 18C 19A 20B 21B

Q22: ACGGAAUCUUC

Q23. Initiation: Binding of mRNA to Ribosome, translation begins; Elongation: adding a.a. to

the polypeptide; Termination: release of ribosome when STOP codon reached.


Review Booklet – short answer questionsQ 25-29: 25C 26A 27A 28B,D 29D

Q30: Absence of Lactose: Repressor protein is free to bind to DNA & prevent transcription. Presence of Lactose: Repressor protein is disabled by Lactose, changed shape prevents it from binding to DNA – transcription proceeds

as RNA polymerase binds to DNA.

Q31. Exons = coding; Introns = junk DNA.Q32. Promoter = identifies beginning of gene locus, binds RNA polymerase; Enhancer = binds proteins that enhance

(improve, promote) transcription. Q 34: A Q 35: A


Review Booklet – short answer questionsQ 6,7,8: See notes on DNA discovery!

Q 9: TCCAGTTACGCG

Q 10: Semi-conservative: half old, half new; template DNA opens up & is copied by enzymes, producing two new DNA molecules, each consisting of one template

strand & one new.

Q12-16: 12D 13B 14C 15A 16E

Q17. C Q 18: B or D both valid

Q19: C Q 20: E Q 21: D

sbi4u molecular genetics review explain the significance of this experiment

Documents

dna polymerase

dna nucleotide

gyrase slide

b slide

p slide

primase slide

dna replication repair

conclusive slide