Basic overview of molecules of living things

1. Four Classes of
Macromolecules
Notes Booklet: Inside Panels
Biological Importance, Dietary Sources,
Functional Groups

2. Carbohydrates
• Biological Importance
• Very abundant in nature
• Preferred energy source for most organisms
• Photosynthesis directly produces glucose
• Cellulose is the most abundant terrestrial biomolecule
• Energy is extracted from glucose during cellular respiration
• Make up cell walls
• plants, bacteria, fungi, algae
• Make up exoskeletons
• arthropods, insects

3. Carbohydrates
Dietary Sources
• Fruits, honey, milk
• Vegetables, grains
Functional Groups
• Hydroxyl (-OH)

4. Lipids
• Biological Importance
• Long term energy storage
• A gram of fat stores twice as much energy as a gram of starch
• Lots of C-H bonds (high-energy bonds)
• Cell membranes would NOT exist (there for no cells, no life as we
know it)
• Phospholipid bilayer
• Biological markers (glycolipids)

5. Lipids
Dietary Sources
• Animal fats
• Plants: nuts, seeds (oils)
Functional Groups
• Hydroxyl (-OH)
• Phosphate (-PO4)
• Carbonyl (-C=O)

6. Proteins
• Biological Importance
• Determine the structure and function
of cells!
• Do the WORK of cells
• Every living cell contains 100s – 1000s of proteins
• ~50% the dry mass of a cell is protein!
• Every dynamic function of a living thing depends on proteins
• Regulate metabolism
• Biomarkers (glycoproteins)
• Human proteome
• Over 19,000 proteins identified
• Expected # of human proteins = 250,000 – one million!

7. Proteins
Dietary Sources
• Animals
• Plants
Functional Groups
• Amino (-NH2)
• Carboxyl (-COOH)

8. Nucleic Acids
• Biological Importance
• Reproduction (cellular and organism level)
• DNA controls its own reproduction
• RNA production is controlled by DNA
• Protein production is controlled by DNA and RNA
• DNA is like computer software
• RNA and proteins are like the hardware
• DNA contains a code for the production of PROTEINS!
• Human genome
• About 20,000 genes code for proteins

9. Nucleic Acids
Dietary Sources
• Almost every type of
food has DNA in it!
• Raw foods = highest
amount of DNA
• Unprocessed
• Uncooked
Functional Groups
• Phosphate (-PO4)
• Hydroxyl (-OH)
• Amino (-NH2)

10. ATP
• Biological Importance
• Life processes require a constant supply of energy
• ATP is the molecular unit of energy for cells to do work
• ATP fuels cellular metabolism!
• ATP stores and transfers energy in cells!
• Covalent bonds between –PO4 are high-energy
• Hydrolysis of ATP releases high energy that is used by the cell to
drive its activities
• Reverse reaction is a special type of reaction called
PHOSPHORYLATION.
• Ingested nutrients are converted to ATP

11. ATP
Dietary Sources
• ATP is not directly
supplied in the diet
• Nutrients in the diet are
converted to ATP in cells
Functional Groups
• Phosphate (-PO4)
• Amino (-NH2)
• Hydroxyl (-OH)