1. Materials Agenda Notebook Pen/Pencil Packet Cell Book-74
01/12/2015- NO GUM PLEASE!
Materials Agenda Notebook Pen/Pencil Packet Cell Book-74
Agenda
Daily question
DNA PPT
Brain pop
Objective: Today we will learn about DNA, RNA, and protein Synthesis
Daily Question: What does DNA stand for?

2. DNA STRUCTURE
EACH CELL IN YOUR BODY CONTAINS DNA…BUT WHAT IS IT? WHAT DOES IT LOOK LIKE?

3. What is DNA? DNA- Deoxyribonucleic acid
stores and passes on genetic information within cells from one generation to the next
James Watson, Francis Crick, Maurice Wilkins, and Rosalind Franklin are three of the scientists credited with the discovery of the structure of the DNA molecule.

4. What does DNA look like?
What do you think?

5. What is DNA made up of?
The sides are made up of deoxyribose sugar and phosphates.
The rungs (steps) are formed by pairs of nitrogen bases

6. What is DNA made up of?
The sugars are chemicals on the outside of the double helix that hold the bases together
Phosphates are the chemicals that join the sugars together

7. What is DNA made up of? There are 4 nitrogen bases in DNA:
Adenine (A)
Guanine (G)
Cytosine (C)
Thymine (T)
Adenine always pairs with Thymine
Cytosine always pairs with Guanine

8. What is a Nucleotide A unit of DNA that consists of: 1 nitrogen base
1 deoxyribose sugar
1 phosphate

9. Different Forms of DNA Chromatin- thread like chains of uncoiled DNA
Chromosome- rod-shaped coils of chromatin
Gene- the basic unit of heredity that consists of a segment of DNA on a chromosome

11. The Master Molecule of Life
DNA
The Master Molecule of Life

12. THE DNA MOLECULE
DNA-Deoxyribonucleic acid- stores and passes on genetic information from one generation to the next
Many scientists believe that the discovery of the structure of DNA was the most important biological breakthrough of the 20th century
James Watson, Francis Crick, and Maurice Wilkins are three of the scientists credited with the discovery of the structure of the DNA molecule.
They discovered that chromosomes are made up of long strands of DNA molecules. It is the DNA molecules in chromosomes that make up genes.
A gene is the basic unit of heredity that consists of a segment of DNA on a chromosome

13. The Structure of DNA
The DNA molecule looks like a twisted ladder, or spiral staircase
The sides of the ladder are made up of molecules of the sugar deoxyribose and phosphate groups. The rungs of the ladder are formed by pairs of substances called nitrogen bases
The sugars are chemicals on the outside of the double helix that hold the bases together
Phosphates are the chemicals that join the sugars together
There are 4 nitrogen bases in DNA:
Adenine (A) Thymine (T)
Guanine (G) Cytosine (C)

14. THE Structure of DNA (cont)
The order of these substances on the DNA molecule determines what type of gene it is.
Adenine always pairs with Thymine
Cytosine always pairs with Guanine
The order of the nitrogen bases on a DNA molecule determines the particular genes on a chromosome
The genetic code is actually the order of nitrogen bases on the DNA molecule (ACGGTTCAAG) for example

15. A Diagram of the DNA molecule

16. DNA Replication

17. When does DNA Replication occur?
Before Mitosis begins- Interphase
Cell Division: Stage1- Interphase

18. Why is DNA Replication an important cell process?
Ensures that each daughter cell will have all of the genetic information it needs to carry out its activities.
Forming daughter cell
DNA (genetic information)
Forming daughter cell
DNA (genetic information)

19. Structure of DNA Sides (DNA Ladder) Rungs (DNA Ladder)
Phosphate
Sides (DNA Ladder)
Alternating molecules of
Deoxyribose sugar
Phosphate
Rungs (DNA Ladder)
Made up of pairs of nitrogen bases
adenine
thymine
cytosine
guanine
Deoxyribose sugar
Nitrogen base

20. Ladder Rungs Letters A, T, G, C
Used to represent the four bases that make up ladder’s rungs
Nitrogen bases on one side of ladder “match up” in specific way with bases on the other side.
Adenine always pairs with Thymine (A-T)
Guanine always pairs with Cytosine (G-C)
Nitrogen Base
Nitrogen base

21. Pairing pattern of the nitrogen bases
key to understanding how DNA replication occurs.

22. Replication Process Step 1:
Two sides of the DNA molecule unwind and separate between paired nitrogen bases on each rung.
Like a zipper unzipping

23. Replication Process Step 2:
Nitrogen bases floating in nucleus pair up with bases on each half of the DNA molecule.
A always pairs with T
G always pairs with C

24. Replication Process Step 3:
Once new bases are attached, two new DNA molecules formed.
Order of bases in each new DNA molecule exactly matches the order in the original molecule.