1. 2.3: Carbon-Based Molecules

2. Carbon-based molecules are the foundation of life.

3. Bonding Properties of Carbon
Carbon forms covalent bonds with up to four other atoms, including other carbon atoms. 1 2
3, 4

4. Structure of carbon-based molecules…
Three general types:
straight chain
H  H   Cl H   H       |   |    |   |    | H - C- C - C - C - C - H       |   |    |  |    |      H   H   H  H   H         
3-chloropentane

5. Structure of carbon-based molecules…
Three general types:
2. Branched chain

6. Structure of carbon-based molecules…
Three general types:
3. Ring

7. Many carbon-based molecules are made of many small subunits bonded together.
Monomers are the individual subunits.
Polymers are made of many monomers.

8. Four Types of Carbon-Based Molecules
Carbohydrates
Lipids
Proteins
Nucleic Acids
ALL four are found in LIVING things.

9. Carbohydrates
Organic molecules made of the elements carbon, hydrogen, and oxygen (CHO)
Includes sugars and starches
Pasta, bread, and fruit are high in carbohydrates

10. Structure of Carbohydrates
Monomer
Monosaccharides
“saccharide” means sugar
simple sugars
Glucose, galactose, fructose

11. Structure of Carbohydrates
Disaccharide
Two monosaccharide molecules bonded together
Sucrose, or table sugar, made of one glucose and one fructose molecule

12. Structure of Carbohydrates
Polymer
Polysaccharides
Chains of monosaccharides
starches, cellulose, and glycogen

13. Function of Carbohydrates
Can be broken down to provide energy for cells.
Glucose-main source of energy for cells, product of photosynthesis
Provide us with energy
Sugar rush then crash
Some carbohydrates are part of cell structure.
Cellulose-makes up the cell wall of plant cells

14. LIPIDS
Organic molecules made of the elements carbon, hydrogen, and oxygen (CHO)
Nonpolar molecules
Do not dissolve in water
Include fats, oils, cholesterol, and wax

15. Structure of Lipids Fatty acids bonded to glycerol.
Glycerol-3 hydroxyl groups
Fatty acids-long carbon chains
Two different types of fatty acids found in fats and oils:
Saturated fatty acids
Unsaturated fatty acids

16. Two Types of Fatty Acids

17. Functions of Lipids Used for long term energy storage
Make up cell membranes
Phospholipid bilayer
Used to make hormones
Testosterone (males) & estrogen (females)
Insulate and waterproof organisms
Cutin-waxy substance that coats leaves of plants to help prevent water loss

18. Lipid Polymer-Phospholipid
Consists of glycerol, two fatty acids (nonpolar tails) and a phosphate group (polar head of molecule)
Makes up ALL cell membranes

19. Lipid Polymer-Triglycerides
Consists of glycerol and three fatty acids
Type of fat found in your blood.
Your body uses them for energy.
You need some triglycerides for good health.
But high triglycerides can raise your risk of heart disease and may be a sign of metabolic syndrome

20. Nucleic Acids
EXTREMELY long carbon-based molecules made of carbon, hydrogen, oxygen, nitrogen, and phosphorus (CHONP)

21. Structure of Nucleic Acids
A phosphate group
nitrogen-containing molecule, called a base
deoxyribose (sugar)
Monomer
Nucleotide
made of a five-carbon sugar, phosphate group, and a nitrogen base.
5 kinds: Adenine, Thymine, Cytosine, Guanine, & Uracil
Polymers
DNA-Deoxyribonuleic Acid
RNA-Ribonucleic Acid

22. Function of Nucleic Acids
DNA
DNA stores genetic information
RNA
RNA builds proteins using information from DNA

23. Proteins
Large organic molecules made of carbon, hydrogen, oxygen, and nitrogen (CHON)
Essential to all life
Foods high in proteins:
Poultry, fish, eggs, beans, nuts, peanut butter, milk

24. Structure of Proteins Monomer Amino acid
Contain an amino group and a carboxyl group
Interact to give a protein its shape and function
Peptide bonds form between amino acids to form chains
Organisms use 20 different amino acids to build proteins
Your body makes 12, others come from food you eat

25. Structure of Proteins
Polymer
Protein
Also called polypeptide
Each protein has a different arrangement of amino acids
Incorrect amino acid sequence and/or arrangement changes the protein’s structure and function

26. Function of Proteins
Building and connecting materials of living things
Collagen-forms bones, tendons, ligaments, and cartilage
Take part in chemical reactions and transport materials
Hormones, antibodies, and enzymes

27. Function of Proteins
Longer-lasting energy source than carbohydrates because broken down more slowly
Involved in eyesight, digestion, etc. as well

28. 2.5: Enzymes Enzymes are catalysts for chemical reactions in living things.

29. Chemical Reactions Reactants  Products
Substances are changed into different substances by breaking and forming chemical bonds
Reactants are changed to form products
Cell growth, reproduction, interaction with the environment, and response to stimuli are the result of a chemical reaction
Reactants  Products

30. Catalysts
Lowers activation energy
Speed up chemical reactions

31. Activation Energy
Energy that needs to be absorbed for a chemical reaction to start
Energy reactants need in order to react
Break bonds and form new ones

32. Rate of Chemical Reactions
Biochemical reactions must occur at certain speeds, or rates, in order to be useful.
Rate of a reaction depends on:
Temperature
Concentration of the chemicals
Surface area

33. Enzymes as Catalysts Enzymes are proteins
Makes reactions that happen in cells possible
Lower activation energy and speed up reaction rate
Without enzymes, many reactions would not happen
Others would occur too slowly for the organism to survive
Enzyme will not be used up or changed during the reaction

34. Structure of Enzymes
Gives reactants a site where they can come together to react
Substrates-reactants affected by enzyme
Substrates bind to the active site
Shape of substrate and active site are complimentary, or opposite
Fit together like a lock and key
substrates (reactants)
enzyme
Substrates bind to an enzyme at certain places called active sites.

35. Lock and Key Model Illustrates how enzymes function
Substrates bind to an enzyme at certain places called active sites.
The enzyme brings substrates together and weakens their bonds.
The catalyzed reaction forms a product that is released from the enzyme.

36. Structure of Enzymes
Allows only certain reactants to bind to the enzyme
An organism may have thousands of different enzymes
Each is specific to one chemical reaction
An enzyme’s function depends on its structure.

37. Functions of Enzymes Energy-releasing enzymes power cell functions
Enzymes in nerve cells produce neurotransmitters to carry impulses from nerves to muscles
Muscle cells have enzymes that are triggered in response to the neurotransmitters

38. Functions of Enzymes Blood contains enzyme carbonic anhydrase
Catalyzes reaction in your blood where carbon dioxide combines with water to form carbonic acid
Makes reaction one million times faster so that carbon dioxide does not build up in your blood, which could be fatal
Enzyme lipase in the pancrease
Speeds up digestion of lipids

39. Functions of Enzymes
Disruptions in homeostasis can prevent enzymes from functioning.
Enzymes function best in a small range of conditions.
Changes in temperature and pH can break hydrogen bonds.
Destroyed at temperatures above 50˚C
Work best at pH of 7