1. DNA and the Development of an Organism

2. Bell Work Create a hypothesis for the following question:
How is it possible that every cell in your body, in a dog’s body, or in a plant’s structure contains the same DNA code?

3. Genetic and Cellular Make-Up of Living Things
Human
Dog
Average number of cells:
100 trillion
Average number of cells:
Varies depending on breed

4. Cell Structure (Organelles and Genetic Material)
Humans and dogs are both EUKARYOTES
Cells with membrane-bound organelles
Similar cellular structure
Cell organelles
Mitochondria, vacuoles, ribosomes, ER, Golgi, nucleus, and more
Genetic material is inside nucleus

5. The Genetic Material
DNA is tightly coiled into chromosomes

7. All Cells Organized the Same

8. Genetic and Cellular Make-Up of Living Things
Human
Dog
Number of chromosomes:
23 pairs
Number of chromosomes:
37 pairs

9. 23 Chromosomes 23 Chromosomes
The Birds and the Bees 101
Sperm
Egg
Contains 23 chromosomes from father
Contains 23 chromosomes from mother 23
Chromosomes 23
Chromosomes

10. The Birds and the Bees 101
Sperm + egg 
Embryo
Embryo will go through cell division and make exact replicas of cell structure and genetic code.

11. Discuss with partner for 30 seconds
The Big Question
If cells divide and create other cells that contain the same genetic code, what must that mean happens to the DNA?
Discuss with partner for 30 seconds

12. Your Challenge
Work with you table partner to create a hypothesis for how DNA replication takes place.
Diagram what it looks like and explain your diagram
Provide labels and a detailed written explanation
Be creative!
You will share your hypothesis with class

13. Things to Recall DNA structure
Double stranded
A-T and G-C
Strands held together by strong H-Bonds between nitrogen bases
Start with 1 strand of DNA and end with 2
Enzymes are used
Proteins that are responsible for directing and speeding up cell activities

14. DNA Replication Notes

15. Bell Work
Do you think the DNA replication process is the same in every organism? Why or why not.
Explain how this might impact how scientists study human DNA replication.

16. DNA Replication Review
4 Corners activity
Each corner represents an answer.
You need to choose your answer in 10 seconds.
Be prepared to share you answer and justify it. A B C D

17. Choose the correct statement:
A – Most cells in a living organism have the same genetic make-up.
B – All cells in a living organism have the same genetic make-up.
C – All cells in a living organism have different genetic make-ups.

18. All cells in a living organism have the same genetic make-up because:
A – They are all made at the same time.
B – They all divide from a single cell (embryo) that is formed when a sperm and egg combine.
C – Not all cells have the same genetic make-up

19. DNA replication is:
A – A process in which a copy of DNA is made using a previously existing strand as a template.
B – A process in which a copy of DNA is made without the use of a template strand.

20. DNA replication results in:
A – 3 strands of DNA with different genetic codes
B – 3 strands of DNA with the same genetic codes
C – 2 strands of DNA with different genetic codes
D – 2 strands of DNA with the same genetic codes

21. The red enzyme below is:
A – Helicase
B – Polymerase
C – Primase
D - Ligase

22. The enzyme laying the RNA primer is:
A – Helicase
B – Polymerase
C – Primase
D - Ligase

23. The enzyme that matches the base pairs of the daughter strand of DNA is:
A – Helicase
B – Polymerase
C – Primase
D - Ligase

24. Because polymerase can only build a new strand of DNA from 5’ to 3’:
A – The leading strand is built in small sections at a time called Okazaki fragments.
B – The lagging strand is built in small sections at a time called Okazaki fragments.
C – Both strands are built in small sections called Okazaki fragments.
D – Both strands are built at the same time as one continuous fragment.

25. A Quick Review

26. Student Choice You can either:
Work on a special project displaying the steps of DNA replication
Get extra help using a model to explain the process of DNA replication