1. DNA, RNA, Transcription & Replication
Genetic Material & Replication

2. Double Helix James Watson & Francis Crick (1950s)
DNA was modeled as a double helix
two strands of DNA twisted with nucleotides linking them together

3. Double Helix Deoxyribose:
The five carbon sugar that is contained within DNA (the D in DNA)

4. Double Helix
Nucleotides:
subunits containing a phosphate group, a five carbon sugar (backbone) & a nitrogen-containing base

5. Double Helix Cont. Purines Pyrimidines
Purines: two rings of carbon and nitrogen (shorter names)
Pyrimidines: one ring (longer names)

6. Chargaff’s Observations
Erwin Chargaff – Biochemist (1949)
Data from different organism DNA analysis concluded that:
Adenine = the amount of Thymine
Guanine = the amount of Cytosine
However the amount of each pair varies from organism to organism = INDIVIDUALITY OF HUMANS

7. Base Pairing
Rules and Chargaff’s observations allow for only two complementary pairs:
Adenine and Thymine
Guanine and Cytosine
Let the student work one out

8. Base Pairing
One strand is used as a template for the other strand during DNA Replication
Let the student work one out

9. DNA Replication & Enzymes
Process of copying DNA using enzymes
Purpose: creates IDENTICAL copies of DNA for mitosis (cell growth and repair)
Location:
Prokaryotic Cells: Cytoplasm
Eukaryotic Cells: Nucleus

10. Roles of Enzymes Step 1: Unwinding DNA Helicase:
an enzyme that unwinds the DNA strand by breaking hydrogen bonds between the pairs
Draw on the board

11. Roles of Enzymes Step 2: Nucleotide Addition DNA polymerase:
An enzyme that adds complementary nucleotides to each exposed strand follow the base pairing rules

12. Roles of Enzymes Step 3: Finishing
The new DNA strand is complementary to the template

14. RNA genetic information transcribed from DNA Complementary pairs:
Adenine and Uracil
Guanine and Cytosine
Sugar: Ribose
Number of strands: One
Three types: messenger RNA (mRNA), ribosomal RNA (rRNA) and transfer RNA (tRNA)

15. Transcription (DNA to mRNA)
Definition:
The method of using DNA as a template to create a strand of mRNA of information
Location: Nucleus
Purpose:
The mRNA will carry the genetic information to the cytoplasm for translation (occurs later)

16. Transcription (DNA to mRNA)
RNA polymerase begins the process and complementary base pairing rules commence the elongation of the strand

18. Video https://www.youtube.com/watch?v=itsb2SqR-R0 (unit 6:00)
Animation/Activity