1. Chapter 6: Chemistry in Biology

2. Atoms Atoms are the smallest unit of an element Three particles
Protons (+ charge)
Electrons (- charge)
Neutrons (no charge)
Nucleus contains protons and neutrons

3. Elements Pure substance made of only ONE type of atom
Arranged in periodic table using atomic #
Atomic # = # of protons OR electrons
Atomic mass = # of protons + # of neutrons

5. Isotopes Atoms of the SAME element that have a different # of neutrons
Ex: Carbon-12,
Carbon-13, Carbon-14
C-13 and C-14 have
MORE neutrons
(weigh more) than C-12

6. Radioactive Isotopes
Radioactive isotopes have unstable nuclei that break down at a constant rate over time
Uses for radioactive isotopes
Dating of rocks and fossils
Kills bacteria on food
Kills cancer
Trace movements of substances within the body

7. Compounds
A substance formed by combination of two or more atoms in definite amounts or ratios
Ex:
Water (cmpd name), H2O (chem. formula)
Carbon dioxide (CO2) – necessary in large amounts,
Carbon monoxide (CO) – deadly in large amounts

8. Compounds, cont.
Chemical properties of cmpd are TOTALLY different than the elements within it
Ex: NaCl (Na-sodium-is a soft metal; Cl-chlorine-is a green poisonous gas) forms table salt!!!

10. Solutions Solute – the substance that is dissolved
Solvent – the substance in which the solute dissolves
Ex: Salt Water
Solute = Salt
Solvent = Water

11. pH Scale Scale measuring amount of H+ (really H3O+) Ranges from 0-14
Neutral: (pH = 7)
Human blood
Pure water
Acidic: (pH = 0-6.9)
Lemons/lemonade
Stomach acid
Basic: (pH = )
Baking soda
Bleach

12. Acid and Base Buffers
Weak acids/bases that help prevent sharp pH changes
Ex: blood has a buffer (to keep it at pH)
Ex: When you drink lemonade, your body produces a buffer to make sure you blood pH doesn’t lower to acidic levels!

14. Water-Why does it support life?
Like a Buffer for Temperature Change
Cohesion:
Water sticks to itself (makes drops)
Adhesion:
Water sticks to OTHER molecules (travels thru plants)
Hydrogen bonding: (Polar )
Type of bond which holds water
molecules together
Universal Solvent (Saliva)

15. The Element Carbon Symbol: C Forms Organic Compounds
Compounds that make up living things
Also called:
Macromolecules
Polymers

16. Carbon, cont. Carbon has 3 chemical advantages:
1) Can make up to 4 covalent bonds
2) Can bond with many elements
3) Can form long chains
-by bonding to itself
-forms millions of different molecules

18. Carbon Compounds Made of two or more smaller molecules
Monomer + Monomer = Polymer
Polymers = puzzle
Monomers = puzzle pieces
Four main types:
1) Carbohydrates 2) Nucleic acid
3) Proteins 4) Lipids

19. Carbohydrates Made of C, H, and O in a 1:2:1 ratio Monomers Dimers
Monosaccharide
Examples: glucose, fructose, galactose
Dimers
Disaccharides
Examples: sucrose and lactose
Polymers
Polysaccharides
Examples: starch, glycogen, chitin, and cellulose

20. Uses for Carbohydrates
Main source of energy for body functions
(through digestion)
Used to build nucleic acids
Structural purposes (cell membrane)

21. Carbohydrates

22. Carbohydrates (Chitin and Cellulose)

23. Lipids (Fats) Made of C, H, and O (phospholipids have P) Triglyceride
Monomers: 1 Glycerol, 3 Fatty Acid Chains
Examples: Fats found in adipose tissue
Phospholipid
Monomers: 1 Glycerol, 2 Fatty Acid Chains
Example: Molecules found in cell membrane
Steroid
Monomers: 4 Carbon ring structure
Example: cholesterol, testosterone, estrogen, and other hormones

24. Lipids

25. Lipids

26. Lipids
Testosterone
Progesterone
Cholesterol

27. Lipids Uses: Store Energy Long-Term (blubber)
Part of Cell Membranes (phospholipids)
Waterproof Coverings (feathers)
Chemical Communication (hormones)

28. Lipids, cont. Four main categories:
1) Fats – butter, margarines, crisco
2) Oils – olive, veggie, canola, corn
3) Waxes – candles, cosmetics, duck’s feathers surrounded by this
4) Steroids – used in communicating b/t cells

30. Nucleic Acids Made of C, H, O, N and P Monomer: Nucleotide (3 Parts)
Uses:
To store hereditary info
To pass hereditary info on to offspring
Phosphate
Sugar
Nitrogen Base

31. Nucleic Acid Parts DNA (Information Storage)
5 Carbon Sugar : Deoxyribose
Nitrogen Bases: A, T, G, C
Phosphate
RNA (Information Transfer)
5 Carbon Sugar: Ribose
Nitrogen Bases: A, U, G, C
Phosphate
Sugar
Nitrogen Base

32. DNA
RNA

33. Protein Made of C, H, O, S, and N Monomer: Polymer:
Amino acids (20 needed in human body)
Polymer:
Polypeptide Chain  Protein
Amino acids are held together by a peptide bond

34. Proteins Uses: Enzymes: Control rate of reactions
Regulate: cell processes
Structure: form bones/muscle
Transport: substances in or out of cells
Fight disease: Antibodies

35. Glycerol AND fatty acids
Monomers and Polymers
Macromolecule
Monomer
Polymer
Carbohydrate
Monosaccharide
Polysaccharide
Protein
Amino acid
Proteins
Lipid
Glycerol AND fatty acids
Lipids
Nucleic acid
Nucleotide
DNA or RNA

36. Chemical Reactions
Chemical reactions are the breaking and forming of chemical bonds
Reactants- original elements or compounds
Products- ending elements or compounds

38. ATP Structure
Adenine
High Energy Bonds
Adenosine
Ribose
Phosphates

39. Energy in Chemical Reactions
Organisms need E to carry out Reactions
All an Organism’s Chemical Reactions = Metabolism
Where do they get Energy (E)?
Plants – photosynthesis/sun
Animals – eating food/consuming others

40. Energy of Reactions (Rxns)
Reaction Types
Energy Releasing
Reaction is spontaneous (not fast, necessarily)
Activation energy – energy need to get the reaction started
At the end of the reaction, energy is released into the environment
Energy Absorbing
Rxn is not spontaneous
Activation energy- energy needed to get the rxn started
At end of the rxn, energy is absorbed from environment

41. Energy Reaction Diagrams

42. Enzymes Catalyst for the reaction (speeds up it’s rate)
Substrate (reactant) enters the active site of the enzyme to form an enzyme-substrate complex
After the rxn, the product leaves
The enzyme remains unchanged

43. Enzymes

44. Action of Enzymes
Speeds up the reaction by lowering activation energy

45. Enzymes uses DNA replication
Digestion (enzymes in your stomach, saliva)
Water removal (from food)
Carbon dioxide removal (from blood)
Fat breakdown (detergents)