1. Condensation and Hydrolysis
Condensation
Two molecules
combine
Hydrolysis
A molecule
splits into two
smaller ones

2. Carbohydrates
• Monosaccharides
– 6 Carbon sugars
• Glucose
• Fructose
• Galactose
– 5 Carbon sugars
• Deoxyribose
• Ribose

3. Carbohydrates
• Oligosaccharides
– Disaccharides
• Sucrose
• Lactose
• Maltose
– Formed by
condensation
reactions

4. Fatty Acids
• Carbon backbone
• Carboxyl group
(- COOH)
• Unsaturated
– One or more double bonds
in backbone
• Saturated
– All single bonds in backbone

5. Triglycerides
• Neutral fats
– Three fatty acids
and a
glycerol
– Condensation
reaction
– Body’s most
abundant
lipid
• Functions:

6. Structure of Amino Acids
• Central carbon
atom
• An amino group
• A carboxyl group
• A hydrogen atom
• One or more atoms
“R Group”

7. Structural Formulas for Some
Amino Acids

8. Peptide Bond Formation
• A type of condensation reaction

9. Levels of Protein Structure
• Primary structure: The sequence of amino acids
in a polypeptide chain.
• Secondary structure: The polypeptide chains
folds on itself to form a helix or a pleated sheet.
• Tertiary structure: The helix and or pleated
sheet fold on itself to form a globular structure
• Quaternary structure: two are more tertiary
structures binding together.

10. Second Level of Protein Structure
• Hydrogen bonds
– Helical coiling
– Sheet-like pattern

11. Third Level of Protein Structure
• Additional folding of secondary structure
• R Group interactions
– Hydrogen bonds
– Disulfide bridges

12. Fourth Level of Protein Structure
• Two or more polypeptide chains joined by
– Weak bonds (Hydrogen bonds)
– Covalent bonds between sulfur atoms and R
groups
• Collagen
• Keratin
• Hemoglobin

13. Structural Changes by
Denaturation
• Disruption of three-dimensional shape of
protein
– Changes in temperature and pH
– Loss of function
• Some proteins have organic compounds
attached
– Glycoproteins
– Lipoproteins

14. Two types of Nucleic acid
• DNA
– Double stranded
– Hydrogen bonds
between strands
– Twisted helically
– Four kinds of
nucleotide monomers
(A, T, C, G)
– Encodes protein-
building instructions
• RNA
– Single stranded
– Four kinds of
nucleotide monomers
(A, U, C, G)
– Do not encode protein-
building instructions
– Key players in the
protein-building
processes
– mRNA, tRNA, rRNA

15. Nucleic Acids - DNA and RNA
• Building
blocks
– Four kinds of
nucleotides
– Differ only in
component
bases

16. Single Strand of Nucleic Acid
A series of
covalently
bonded
nucleotides
Nucleotides
form together by
condensation
reactions

17. DNA

18. In Conclusion
• Organic compounds have elements
covalently bonded to carbon atoms
• Living cells assemble organic compounds:
lipids, carbohydrates, proteins, and nucleic
acids
• The building blocks are amino acids,
nucleotides, simple monosaccharide sugars,
and fatty acids
• Complex carbohydrates are energy storage
forms and structural materials

19. In Conclusion
• Lipids are used as energy storage and
structural components
• Proteins are made of amino acids. They form
structural part of the body as well and
enzymes.
• Nucleic acids are the basis of inheritance
and reproduction
• developed by M. Roig