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Biology 12 Mrs. Knowles DNA & Gene expression: Chapters 24 & 25 Discovery of DNA 1. Chargaff’s rule 2. Hershey and Chase experiment 3. Francis & Crick’s model

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Page 1: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

DNA & Gene expression: Chapters 24 & 25

Discovery of DNA

1. Chargaff’s rule

2. Hershey and Chase experiment

3. Francis & Crick’s model

Page 2: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Structure of DNA

Polynucleotide with three subunits:

1)

2)

3)

Purines:

Page 3: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Pyrimidines:

Double helix:

Complementary base pairing:

Page 4: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Antiparallel strands

Replication

Purpose:

semiconservative process:

STEPS:

1) DNA helicase2) DNA polymerase3) DNA ligase

Results:

Page 5: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

RNA structure

DNA RNASugar

Bases

Strands

Helix?

Page 6: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Types of RNA:

1) Messenger RNA (mRNA)

2) Ribosomal RNA (rRNA)

3) Transfer RNA (tRNA)

Page 7: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Checkpoint:

Page 505: 1-14

Differentiate between purines and pyrimidines including examples of each.

What three components make up DNA?

What are the structural differences between ribose and deoxyribose? Between thymine and uracil?

Page 8: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Gene expressionOverall goal:

Overall process:

Gene:

Page 9: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Transcription

Recall that the overall goal is:

Location of transcription:

1) Synthesis of mRNAPromoter region:

RNA polymerase

Page 10: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

2) Processing of mRNA (primary -> mature mRNA)A) Cap

B) Poly-A tail

C) Introns removed, exons joined together

Introns:

Exons:

Ribozyme:

3) Mature mRNA leaves nucleus

Page 11: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Translation

Overall purpose:

The triplet code:

Why triplet?

Codon:

Start codon:

Stop codons:

Page 12: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

tRNA:

its role:

anticodon:

Page 13: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Ribsomes

Made of:

Made at:

Binding sites:

Polyribosome:

Page 14: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Steps in translation:

1) Chain initiationWhat is involved:

Step 1:

Step 2:

Page 15: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

2) Chain elongation

Step 3:

Step 4:

Step 5:

Step 6:

Page 16: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

3) Chain termination

Step 7:

Step 8:

Page 17: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Levels of gene control

1) Unpacking of DNA

2) Transcription

3) mRNA processing

4) translation

Page 18: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

5) protein activity

6) signaling between cells

When gene control fails: cancer

Characteristics of cancer cells:

Page 19: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Proto-oncogenes

Tumor-suppressor genes

Page 20: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

Gene mutations

Definition:

Causes:

i. Errors in replication

ii. Mutagens

iii. transposons

Types of mutations:

i. Frameshift mutations

Page 21: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

ii. Point mutations

DNA Technology

1) Cloning

i) Reproductive cloning

ii) Therapeutic cloning

2) Recombinant DNA (rDNA)

Page 22: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

3) Polymerase chain reaction

4) Fingerprinting

Biotechnology-genetic engineering

1) Transgenic bacteria

2) Transgenic plants

Page 23: Web viewTumor-suppressor genes. Gene mutations. Definition: Causes: Errors in replication. Mutagens. transposons. Types of mutations: Frameshift mutations. Point mutations

Biology 12Mrs. Knowles

3) Transgenic animals

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