dna, rna, and protein synthesis chapter 10 section 1 discovery of dna meischer levene griffith avery...
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DNA, RNA, and Protein SynthesisChapter 10
Section 1 Discovery of DNA
Meischer
Levene
Griffith
Avery
Hershey and Chase
Section 2 DNA Structure
Section 3 DNA Replication
Section 4 Protein Synthesis
Section 1 Discovery of DNAChapter 10
Objectives
• Relate how Griffith’s bacterial experiments showed that a hereditary factor was involved in transformation.
• Summarize how Avery’s experiments led his group to conclude that DNA is responsible for transformation in bacteria.
• Describe how Hershey and Chase’s experiment led to the conclusion that DNA, not protein, is the hereditary molecule in viruses.
Section 1 Discovery of DNAChapter 10
WHAT is the Genetic Material?
• History and Scientist – (http://dnaftb.org/15/concept/)– 1869 Miescher– Early 1900s, Levene– 1928, Griffith– 1940’s Avery– 1952 Hershey and Chase
Section 1 Discovery of DNAChapter 10
Griffith’s Experiments
• Griffith’s experiments showed that hereditary material can pass from one bacterial cell to another.
• The transfer of genetic material from one organism to another organism is called transformation (60427).
• http://dnaftb.org/17/concept/index.html
Chapter 10
Griffith’s Discovery of Transformation
Section 1 Discovery of DNA
Section 1 Discovery of DNAChapter 10
Avery’s Experiments
• Also worked with bacteria cells (Streptococcus pneumonia) and mice
• Avery’s work showed that DNA, is the hereditary material that transfers information between bacterial cells.
Section 1 Discovery of DNAChapter 10
Hershey-Chase Experiment (61132)• Hershey and Chase confirmed that DNA, and not protein,
is the hereditary material.
– Used bacteriaphase, which is a virus that infects bacteria
– Viruses have DNA inside and protein coat outside. • DNA has phosphorus (only phosphorus goes into
bacteria during infection)• Proteins have sulfur
• http://dnaftb.org/18/concept/index.html
Chapter 10The Hershey-Chase Experiment
Section 1 Discovery of DNA
DNA, RNA, and Protein SynthesisChapter 10
Section 1 Discovery of DNA
Meischer
Levene
Griffith
Avery
Hershey and Chase
Section 2 DNA Structure
Section 3 DNA Replication
Section 4 Protein Synthesis
DNA, RNA, and Protein SynthesisChapter 10
Section 1 Discovery of DNA
Section 2 DNA Structure
Nucleotide (sugar, phosphate and nitrogen base)
Bonding within DNA molecules
Complementary Base Pair Rule
Watson and Crick (Franklin and Wilkins)
Why Twist?
Section 3 DNA Replication
Section 4 Protein Synthesis
Section 2 DNA StructureChapter 10
Objectives
• Evaluate the contributions of Franklin and Wilkins in helping Watson and Crick discover DNA’s double helix structure.
• Describe the three parts of a nucleotide.
• Summarize the role of covalent and hydrogen bonds in the structure of DNA.
• Relate the role of the base-pairing rules to the structure of DNA.
Chapter 10Nucleic Acids
• A nucleic acid is a large and complex organic molecule that stores and transports genetic information
• Made of: ______, _____, ______, and _______.• Monomer is called _____________________
• Five carbon sugar named ____________________• Phosphate Group• Nitrogen base
• Guanine• Adenine• Thymine• Cytosine
Section 2 DNA Structure
Chapter 10
Structure of DNA : Nucleotides
Section 2 DNA Structure
Section 2 DNA StructureChapter 10
DNA STRUCTURE
• Bonds Hold DNA Together– Nucleotides along each DNA strand are linked
by covalent bonds between the sugars and phosphates. – Antiparallel: two strands run on opposite
directions. – Complementary nitrogenous bases are
bonded by hydrogen bonds and connect the two strands together.
Section 2 DNA StructureChapter 10
DNA STRUCTURE
• Hydrogen bonding between the complementary base pairs, • Guanine pairs with
Cytosine (3 H-bonds)• Adenine pairs with
Thymine (2 H-bonds)
• 60171
Section 2 DNA StructureChapter 10
DNA STRUCTURE
1953: Watson and Crick created a model of DNA by using Franklin’s and Wilkins’s DNA diffraction
X-rays.
DNA is made of two nucleotide strands that wrap around each other in the shape of a double helix.
Chapter 10
Structure of DNA
Section 2 DNA Structure
Chapter 10
Structure of DNA
Section 2 DNA Structure
DNA, RNA, and Protein SynthesisChapter 10
Section 1 Discovery of DNA
Section 2 DNA Structure
Nucleotide (sugar, phosphate and nitrogen base)
Bonding within DNA molecules
Complementary Base Pair Rule
Watson and Crick (Franklin and Wilkins)
Why Twist?
Section 3 DNA Replication
Section 4 Protein Synthesis
DNA, RNA, and Protein SynthesisChapter 10
Section 1 Discovery of DNA
Section 2 DNA Structure
Section 3 DNA Replication
STEPS and Enzymes used
Semi-conservative Replication
Correct Errors
Section 4 Protein Synthesis
Section 3 DNA ReplicationChapter 10
Objectives
• Summarize the process of DNA replication.
• Identify the role of enzymes in the replication of DNA.
• Describe how complementary base pairing guides DNA replication.
• Compare the number of replication forks in prokaryotic and eukaryotic cells during DNA replication.
• Describe how errors are corrected during DNA replication.
Section 3 DNA ReplicationChapter 10
How DNA Replication Occurs
• DNA replication is the process by which DNA is copied in a cell before a cell divides.
Occurs during the S phase of the cell cycle
Section 3 DNA ReplicationChapter 10
How DNA Replication Occurs, continued
• Steps of DNA Replication – 1. Replication begins with the separation of the
DNA strands by helicases. – 2. Then, DNA polymerases form new strands by
adding complementary nucleotides to each of the original strands.
– Lagging strand and Okazaki Fragments– 3. Each new DNA molecule is made of one strand
of nucleotides from the original DNA molecule and one new strand. This is called semi-conservative replication.
Chapter 10DNA Replication (60172)
Section 3 DNA Replication: Video
Chapter 10
Replication Forks Increase the Speed of Replication
Section 3 DNA Replication
Section 3 DNA ReplicationChapter 10
DNA Errors in Replication :
• Changes in DNA are called mutations. • Due to mutagens or carcinogens
• These can be environmental factors• Smoking , radiation, UV Light.• Video
• DNA proofreading and repair prevent many replication errors.
DNA, RNA, and Protein SynthesisChapter 10
Section 1 Discovery of DNA
Section 2 DNA Structure
Section 3 DNA Replication
STEPS and Enzymes used
Semi-conservative Replication
Correct Errors
Section 4 Protein Synthesis
DNA, RNA, and Protein SynthesisChapter 10
Section 1 Discovery of DNA
Section 2 DNA Structure
Section 3 DNA Replication
Section 4 Protein Synthesis
Central Dogma of Molecular Genetics
Compare RNA and DNA molecules
Steps of Protein Synthesis
Transcription, Genetic Code, and Translation
Human Genome
Section 4 Protein SynthesisChapter 10
Objectives
• Outline the flow of genetic information in cells from DNA to protein.
• Compare the structure of RNA with that of DNA.
• Describe the importance of the genetic code.
• Compare the role of mRNA, rRNA,and tRNA in translation.
• Identify the importance of learning about the human genome.
Section 4 Protein SynthesisChapter 10
Flow of Genetic Information
• The flow of genetic information can be symbolized as
DNA RNA protein.
Section 4 Protein SynthesisChapter 10
RNA Structure and Function
• RNA also made of _________________• Sugar is _____________• Phosphate• Nitrogen bases are
• ____________• ____________• ____________• ____________
• RNA is single stranded and is shorter than DNA.
Compare
DNA and
RNA
60175
Section 4 Protein SynthesisChapter 10
RNA Structure and Function
• Types of RNA– Cells have three major
types of RNA: • messenger RNA
(mRNA)• ribosomal RNA
(rRNA)• transfer RNA
(tRNA)
Section 4 Protein SynthesisChapter 10
RNA Structure and Function (60176)
• mRNA (messenger) carries the genetic “message” from the nucleus to the cytoplasm. (copy of blueprint)
• rRNA (ribosomal) is the major component of ribosomes. (factory)
• tRNA (transfer) takes specific amino acids to the ribosome to make proteins. (shuttle train or taxi for supplies)
Section 4 Protein SynthesisChapter 10
Steps to Protein Synthesis (made of amino acids)Transcription
• During transcription, DNA acts as a template for directing the synthesis of RNA. Video
• DNA is A T G C G C A T T A G C• mRNA is ____________________________
Chapter 10
Transcription:Video
Section 4 Protein Synthesis
Section 4 Protein SynthesisChapter 10
Steps to Protein SynthesisGenetic Code• The nearly universal genetic code identifies the
specific amino acids coded for by each three-nucleotide mRNA codon.
• AUG is a codon for Methionine amino acid. • CCC is a codon for Proline amino acid.
Section 4 Protein SynthesisChapter 10
Section 4 Protein SynthesisChapter 10
Steps to Protein Synthesis Translation
• Steps– During translation, amino acids are picked up and
organized according to mRNA. – tRNA is picking up amino acids from the cytoplasm– mRNA codons move through the ribosome– tRNAs add specific amino acids to create a growing
polypeptide chain (future protein. – The process continues until a stop codon is reached
and the newly made protein is released.
Chapter 10
Translation: Assembling Proteins Video
Section 4 Protein Synthesis
video
Section 4 Protein SynthesisChapter 10
The Human Genome
• The entire gene sequence of the human genome, the complete genetic content, is now known.
• To learn where and when human cells use each of the proteins coded for in the approximately 30,000 genes in the human genome will take much more analysis.
DNA, RNA, and Protein SynthesisChapter 10
Section 1 Discovery of DNA
Section 2 DNA Structure
Section 3 DNA Replication
Section 4 Protein Synthesis
Central Dogma of Molecular Genetics
Compare RNA and DNA molecules
Steps of Protein Synthesis
Transcription, Genetic Code, and Translation
Human Genome
Section 2 Cell Division and CancerChapter 11
Objectives
• Summarize the effects of mutations in causing cancer.
• Compare the characteristics of cancer cells with those of normal cells.
Section 2 Gene Expression in Development and Cell DivisionChapter 11
Gene Expression, Cell Division, and Cancer
• Mutations of proto-oncogenes, which regulate cell growth, or tumor-suppressor genes, which prevent cell division from occurring too often, may lead to cancer.
• Cancer is the uncontrolled growth of abnormal cells.
Chapter 11
Effect of Mutation on Gene Expression
Section 2 Gene Expression in Development and Cell Division
Chapter 11
Section 2 Gene Expression in Development and Cell DivisionChapter 11
Gene Expression, Cell Division, and Cancer, continued
• Gene Expression in Cancer– Unlike normal cells,
cancer cells continue to divide indefinitely, even if they become densely packed.
– Cancer cells will also continue dividing even if they are no longer attached to other cells.
Section 2 Gene Expression in Development and Cell DivisionChapter 11
Gene Expression, Cell Division, and Cancer, continued
• Causes of Cancer– A carcinogen is any substance that can induce or
promote cancer. – Most carcinogens are mutagens, substances that
cause mutations.