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Nucleic Acids Made of Nucleotides
Nucleotide - 1 Sugar; 1 Phosphate; 1 Nitrogen Base 2 types DNA RNA
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DNA Structure Ladder shape with 2 chains of sugar-phosphate-sugar-phosphate... connected by pairs of Nitrogen Bases
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Nucleic Acids - DNA Structure
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Nucleic Acids - DNA Structure
Nitrogen bases connected by “hydrogen bonds” [weak] Ladder is twisted into double spiral - Double Helix Sugar is Deoxyribose 2 Types of Nitrogen bases Adenine & Guanine Thymine & Cytosine Adenine always bonds with Thymine Guanine always bonds with Cytosine
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Nucleic Acids RNA - Ribonucleic Acid
Helps transport Genetic information Helps in the making of Protein [Protein Synthesis] Structure - One half of a DNA Ladder shape
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Nucleic Acids - RNA - Structure
Sugar is Ribose 1 Nitrogen base substitution RNA has no THYMINE Rna has URACIL instead
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REPLICATION (DNA makes a copy of itself) 1- Enzymes break hydrogen bonds between nitrogen bases 2- DNA ‘unzips’ 3- Free DNA nucleotides bond to exposed nitrogen bases on both sides [ A bonds to T ; C bonds to G ] 4- Enzymes link nucleotides together RESULT- 2 identical strands of DNA
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Protein Synthesis A process in 2 parts Transcription Translation
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Protein Synthesis - Transcription
#1 Transcription (DNA makes a messenger RNA blue print) -Enzymes unzip DNA like in replication -RNA nucleotides bond to one side of unzipped DNA -RNA nucleotides have ribose instead of deoxyribose and have uracil instead of thymine -RNA nucleotides bond together sugar-phosphate to become mRNA -New mRNA breaks off from DNA and goes to ribosome -DNA zips back up
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Protein Synthesis - Translation
#2 Translation (mRNA information is used to make protein) -mRNA goes to ribosome -Ribosome (made of rRNA) “reads” the first 3 nitrogen bases (Called a codon) and “calls for” a tRNA with the matching anticodon
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Protein Synthesis - Translation
#2 Translation (mRNA information is used to make protein) -mRNA goes to ribosome -Ribosome (made of rRNA) “reads” the first 3 nitrogen bases (called a codon) and “calls for” a tRNA with the matching anticodon Amino Acid tRNA (transfer RNA) Anticodon
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Protein Synthesis - Translation
-tRNA bonds to mRNA -Ribosome reads the next codon (3 bases) and “calls for” the next tRNA Next tRNA bonds to mRNA -Enzymes link the amino acids together -The first tRNA leaves its amino acid and goes to get more The ribosome moves on and so on, and so on until the protein is complete
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The Genetic Code The genetic code shows the amino acid to which each of the 64 possible codons corresponds. To decode a codon, start at the middle of the circle and move outward.
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The Genetic Code The genetic code shows the amino acid to which each of the 64 possible codons corresponds. To decode a codon, start at the middle of the circle and move outward.
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MUTATION -Change in genetic information that can be inherited
2 main types -Chromosomal Mutations -Gene Mutations
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MUTATION Chromosomal Mutations major types -Nondisjunction
-Translocation [Crossing Over] - 2 chromosomes tangle with each other and switch parts
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MUTATION Gene Mutations Mutations that affect only one gene 2 types
-Point Mutation (Substitution) - One nucleotide is substituted for another -Frameshift Mutation- One nucleotide is added (addition) or deleted (deletion)
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MUTATION Which of these two types of gene mutations can create the most change? Justify your answer.
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Replication
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Protein Synthesis
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