1. Proteins and DNA
Chapter 3

2. Proteins Proteins are polymers constructed from 20 amino acids
Amino acids are linked by dehydration
Covalent bonds between amino acids are called peptide bonds

3. Amino acid structure Each amino acid contains A central carbon
An amino group
A carboxylic acid group
A lone Hydrogen
An R group which varies and makes each AA different

7. Levels of protein organization
Primary structure- DNA directions determine the sequence of 20 amino acids in a long chain. Each protein has a different sequence
2. Secondary structure – Hydrogen bonds form two folding patterns
Alpha helix- coil
Beta pleated sheet- accordion
Or no pattern
Random coil- no shape

8. Levels of protein structure
3. Tertiary structure- R groups of different Amino acids bond and create distorted shapes. Protein is called a globular protein. Most proteins are now ready to work 4. Quaternary structure- some proteins require several globular units to do their job collagen is made of three strands hemoglobin is made of four globs

10. Denaturing Proteins
When proteins are exposed to high temperatures or extreme pH the secondary, tertiary and quaternary bonds unravel
Protein loses its shape and cannot do its function

12. Nucleic Acids DNA- deoxyribonucleic acid RNA- ribonucleic acid
Made of nucleotides (monomers)
Nucleotides are made of
A phosphate
One of two different five carbon sugars
One of five different nitrogen bases

13. DNA Nucleotide structure Phosphate Deoxyribose – sugar
Possible Nitrogenous bases
Adenine (A)
Thymine (T)
Guanine (G)
Cytosine (C)

14. RNA Nucleotide structure Phosphate Ribose – sugar Nitrogen bases
Adenine
Uracil
Guanine
Cytosine