1. Carbon The LEGO of biological molecules!
Copyright Cmassengale

2. Carbon-based Molecules
Although a cell is mostly water, the rest of the cell consists mostly of carbon-based molecules
Organic chemistry is the study of carbon compounds
Copyright Cmassengale

3. Organic molecules are complex molecules of life, built on a framework of carbon atoms
Carbohydrates
Lipids
Proteins
Nucleic Acids

4. Carbon is a Versatile Atom
It has four electrons in an outer shell that holds eight
Carbon can share its electrons with other atoms to form up to four covalent bonds
Copyright Cmassengale

5. Copyright Cmassengale
Hydrocarbons
The simplest carbon compounds …
Contain only carbon & hydrogen atoms
Copyright Cmassengale

6. Uses of Organic Molecules
A typical cell in your body has about 2 meters of DNA
A typical cow produces over 200 pounds of methane gas each year
Copyright Cmassengale

7. Isomers
Isomers are compounds with the same molecular formula but different structures and properties:
Structural isomers have different covalent arrangements of their atoms
Geometric isomers have the same covalent arrangements but differ in spatial arrangements
Enantiomers are isomers that are mirror images of each other
Animation: Isomers
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

8. Figure 4.7 Three types of isomers
Pentane
2-methyl butane
(a) Structural isomers
cis isomer: The two Xs are
on the same side.
trans isomer: The two Xs are
on opposite sides.
(b) Geometric isomers
Figure 4.7 Three types of isomers
L isomer
D isomer
(c) Enantiomers

9. Enantiomers are important in the pharmaceutical industry
Two enantiomers of a drug may have different effects
Differing effects of enantiomers demonstrate that organisms are sensitive to even subtle variations in molecules
Animation: L-Dopa
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

10. Effective Enantiomer Ineffective Enantiomer Drug Condition Pain;
Fig. 4-8
Effective
Enantiomer
Ineffective
Enantiomer
Drug
Condition
Pain;
inflammation
Ibuprofen
S-Ibuprofen
R-Ibuprofen
Figure 4.8 The pharmacological importance of enantiomers
Albuterol
Asthma
R-Albuterol
S-Albuterol

11. Carbon can use its bonds to::
Attach to other carbons
Form an endless diversity of carbon skeletons
Copyright Cmassengale

12. Large Hydrocarbons:
Are the main molecules in the gasoline we burn in our cars
The hydrocarbons of fat molecules provide energy for our bodies
Copyright Cmassengale

13. Shape of Organic Molecules
Each type of organic molecule has a unique three-dimensional shape
The shape determines its function in an organism
Space-filling models show how
Atoms sharing electrons overlap
Copyright Cmassengale

14. Functional Groups are:
Groups of atoms that give properties( such as polarity, acidity) to the compounds to which they attach
Lost Electrons
Gained Electrons
Copyright Cmassengale

15. Common Functional Groups
Copyright Cmassengale

16. Effects of Functional Groups: Sex Hormones

17. What cells Do to Organic Compounds
Metabolism
Activities by which cells acquire and use energy to construct, rearrange, and split organic molecules
Allows cells to live, grow, and reproduce
Requires enzymes (proteins that increase the speed of reactions)

18. What cells Do to Organic Compounds
Large molecules are called polymers
Polymers are built from smaller molecules called monomers
Biologists call them macromolecules
Copyright Cmassengale

19. Copyright Cmassengale
Examples of Polymers
Proteins
Lipids
Carbohydrates
Nucleic Acids
Copyright Cmassengale

20. Most Macromolecules are Polymers
Polymers are made by stringing together many smaller molecules called monomers
Nucleic Acid Monomer
Structural model: each line is a covalent
bond; two lines are double bonds;
three lines are triple bonds.
Copyright Cmassengale

21. Linking Monomers
Cells link monomers by a process called condensation or dehydration synthesis (removing a molecule of water)
Remove H
H2O Forms
Remove OH
This process joins two sugar monomers to make a double sugar
Copyright Cmassengale

23. Breaking Down Polymers
Cells break down macromolecules by a process called hydrolysis (adding a molecule of water)
Water added to split a double sugar
Copyright Cmassengale

24. Macromolecules in Organisms
There are four categories of large molecules in cells:
Carbohydrates
Lipids
Proteins
Nucleic Acids
Copyright Cmassengale

25. Structure Dictates Function
We define cells partly by their capacity to build complex carbohydrates, lipids, proteins, and nucleic acids
All of these organic compounds have functional groups attached to a backbone of carbon atoms.
Most biological molecules have at least on functional group ( a cluster of atoms that imparts specific chemical properties to a molecule)

26. Copyright Cmassengale
End
Copyright Cmassengale