1. DNA, RNA, Protein Synthesis
DNA Structure
DNA Replication : DNA  DNA
RNA Structure
Protein Synthesis
Transcription : DNA RNA
Translation : mRNA  amino acid

2. Human Genotype The human genotype contains 46 chromosomes
Each chromosome has 2 chromatid legs
Each chromatid leg has thousands of genes
Each gene has thousands of DNA nucleotides in loose strands called chromatin

5. Role of DNA
1) DNA stores the genetic information in the nucleus until is time to pass the genetic information on to progeny
2) DNA is the blueprint for the cell to make proteins

6. DNA Structure DNA is a double helix = twisted ladder
DNA is a polymer of DNA monomers
Eg. DNA nucleotides in a DNA strand are like beads in a necklace

8. DNA Nucleotide Each nucleotide has 3 sub-components
1) 5 carbon sugar called deoxyribose
2) phosphate group
3) nitrogen-containing base

9. DNA Nucleotide Base
There are four bases: adenine (A), thymine (T), guanine (G) and cytosine (C)
The name of the DNA nucleotide is the name of the base
The DNA nucleotides undergo “complementary” base-pairing:
A=T , T=A, G=C, C=G

11. DNA Nucleotides Hydrogen bonding between complementary bases :
A=T T=A G=C C=G
Keeps the two DNA strands together in the double helix shape

13. DNA Replication
DNA Replication = 1 “Parent” Double Strand DNA  2 “Progeny” Double Strand DNA
DNA Replication is called “Semi-conservative” because each progeny double strand DNA has one original parent DNA strand and one new DNA strand

15. DNA Replication DNA replication requires 3 enzymes:
DNA helicase : “unzips” the double helix by breaking hydrogen bonds between bases
DNA polymerase : attaches new DNA nucleotide to complementary DNA nucleotide in parent DNA strand
DNA ligase: ties the strands back together

18. RNA Structure DNA Double helix Deoxyribose sugar A=T, T=A, G=C, C=G
DNA remains in nucleus
RNA
Single strand
Ribose sugar
Uracil base replaces Thymine base
A=U, T=A, G=C, C=G
RNA is made in nucleus and moved to cytoplasm

20. Role of RNA
Messenger RNA : carries protein synthesis information stored in DNA in the nucleus to the ribosome in the cytoplasm
Transfer RNA: brings amino acids to the ribosome for protein synthesis
Ribosomal RNA: combines with proteins to make the ribosomes