1. DNA & Genes
6A (RS) DNA: Identify components of DNA, and describe how information for specifying the traits of an organism is carried in the DNA

2. What is DNA? DNA - deoxyribonucleic acid
A chemical substance that’s present in the nucleus of all cells in all living organisms
controls the production of proteins

3. DNA is found in the chromosomes in the nucleus.

4. Modern Genetics
DNA of the chromosomes is the genetic material that is passed from generation to generation(Heredity)
Genetics is the study of heredity
Genes are sections of DNA.

5. Eukaryotic Chromosomes
Contain DNA and proteins called histones
Tightly packed DNA and proteins form chromatin
During mitosis, the chromatin condenses to form tightly packed chromosomes

6. Nucleic Acids
Complex molecule that stores and communicates genetic information
Two types of Nucleic Acids
DNA- deoxyribonucleic acid
RNA – ribonucleic acid

7. DNA Shape
Double Helix
The ladder arrangement of DNA is twisted, producing the characteristic double-helix appearance

8. DNA Structure DNA is made up of nucleotides
Nucleotides Have Three Parts
Phosphate group
Simple Sugar (5-carbon sugar)
Nitrogen Base

9. Ribose & Deoxyribose
Ribose is a sugar, like glucose, but with only five carbon atoms in its molecule
Deoxyribose is almost the same but lacks one oxygen atom
Both molecules may be represented by the symbol

10. The Nitrogen Bases Adenine (A) Thymine (T) Cytosine (C) Guanine (G)
The most common organic nitrogen bases are:
Adenine
(A)
Thymine
(T)
Cytosine
(C)
Guanine
(G)

11. Pairing Nitrogen Bases
Adenine forms a bond with Thymine (A-T)
Cytosine bonds with Guanine (C-G)
Adenine
Thymine
Cytosine
Guanine
Bases are held together by a hydrogen bond

12. Nucleotides PO4 adenine deoxyribose
Phosphate Group + Deoxyribose+ one base=
(or Ribose)
Nucleotide
adenine
deoxyribose
PO4

13. Joined nucleotides
PO4
sugar-phosphate
backbone
+ bases
A molecule of DNA is formed by millions of nucleotides joined together in a long chain
Do you remember what kind of chemical reaction joins monomers together by removing water?

14. PO4
thymine
adenine
cytosine
guanine

15. Label the Parts