1. The Chemistry of Life
Chapter 2

2. vocabulary Atom the most basic and smallest unit of matter Nucleus
center of the atom
holds protons and neutrons
Contains subatomic particles
called protons, electrons and neutrons
Discuss next diagram

3. Atoms Nucleus; Protons; + charge; mass = 1AMU
Neutrons; no charge; mass = 1AMU
Electrons: - charge; no mass

4. vocabulary Element specific atoms of one type form pure substances
Over 100 elements/pure substances exist
Ca calcium
H hydrogen
O oxygen
Na sodium
C carbon

5. Periodic table Elements are organized in a table and assigned a number
Number atomic number
Table periodic table
This your new friend…at least for this next unit!
Get use to it

6. Atomic Number Defines the element Is equal to the number of protons
Is equal to the number of electrons in a neutral atom
Always the whole number

7. C 6 Carbon 12.011 Atomic Mass Atomic Number
An Element in the Periodic Table
Section 2-1
Atomic Number 6 C
Carbon
12.011
Atomic Mass
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9. Atomic Mass
Is equal to the number of protons and neutrons in the nucleus of the atom
May not be a whole number on the periodic table
In biology you may round up the mass number to a whole number

10. To find the number of Neutrons
Atomic mass – atomic number = Neutrons

11. Isotopes of Carbon
Nonradioactive carbon-12
Nonradioactive carbon-13
Radioactive carbon-14
6 electrons
6 protons
6 neutrons
6 electrons
6 protons
7 neutrons
6 electrons
6 protons
8 neutrons
Isotopes have the same number of protons and electrons but have a different number of neutrons

12. Time to play…
Candium isotope lab!!!

13. Energy Levels
1st 2e-
2nd 8e-
3rd 8e-
4th18e-

14. Valence Electrons
Outer level Electrons
Bonding Electrons

15. Image Source: SStevens 2002

16. Image Source: SStevens 2002

17. Image Source: SStevens 2002

18. Image Source: SStevens 2002

19. Image Source: SStevens 2002

20. Image Source: SStevens 2002

21. How are things kept together
Ionic Bonds
Transferring of electrons
Create ions
Opposite charged particles are attracted to each other
Electrons are gained/lost
Covalent bonds
Can create slightly different charges
Strongest chemical bond
Orbitals/shells overlap and electrons bounce back and forth
Van der Waals forces
Happens when molecules are super close together
Hydrogen bonding-weak bonds

22. Drawing molecules showing Ionic Bonding
Draw all atoms showing protons, and electrons in their energy levels
Decide which electrons must be transferred in order to fill all of the atoms outer level
Draw the electrons being transferred
Show the resulting charge on the Ions

23. Ionic Bonding Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na+)
Chloride ion (Cl-)
Transfer
of electron
Protons +11
Electrons -11
Charge
Protons +17
Electrons -17
Charge
Protons +11
Electrons -10
Charge
Protons +17
Electrons -18
Charge

24. Ionic Bonding Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na+)
Section 2-1
Sodium atom (Na)
Chlorine atom (Cl)
Sodium ion (Na+)
Chloride ion (Cl-)
Transfer
of electron
Protons +11
Electrons -11
Charge
Protons +17
Electrons -17
Charge
Protons +11
Electrons -10
Charge
Protons +17
Electrons -18
Charge

25. Draw the following molecules showing them form ionic bondsKF
MgCl2

26. Chemical formulas CO2 3 Atoms H2O 3 Atoms Ca(OH)2 5 Atoms
2C6H12O atoms

27. Covalent Bonding Sharing of electrons No ions are formed
Sharing of electrons holds it together.

28. Guided/independent practice
Chemistry worksheet…time to think!

29. Water Most abundant compound found in living things.
Water is a molecule (H2O)
Water is a polar molecule. (unequal sharing of electrons)
Hand out chemistry worksheet!

30. Water Facts It is a neutral molecule
Water is the single most abundant compound on earth
It expands when it freezes
It floats when frozen
What advantage does this play in the survival of fish and plants
75% of earth is water
The human body is 70% water
Ph of 7.0

31. Properties of Water Its Polar High heat capacity
It has a negative end and a positive end
Uneven sharing of electrons
High heat capacity
Absorb

32. Hydrogen bonds
Because of the uneven charge water atoms can attract each other
Cohesion: attraction between molecules of the same substance
Insects walking on water
Adhesion: attraction between molecules of different substances
Water drawn up a plant (capillary action)

33. Hydrogen Bonding

34. Water demo
Water lab

35. Acids, Bases, and the pH scale
Water is the universal solvent
Most compounds will dissolve in water
Remember 75% of most animals are water
H20 → H+ + OH-
Water → Hydrogen ion + Hydroxide ion
Only about one water molecule in 55 million will form a hydrogen ion
H+ = OH- , so water is always neutral

36. PH scale – measures the concentration of H+ and OH- ions.
Ranges from 0-14
At 7 the concentration of H+ and OH- is equal. (pure water)
Acid – H+ ions, 0-6
Alkaline or base- OH- ions, 8-14
Each step represents a factor of 10

37. pH Scale Increasingly Basic Neutral Increasingly Acidic Oven cleaner
Bleach
Ammonia solution
Increasingly Basic
Soap
Sea water
Human blood
Neutral
Pure water
Milk
Normal
rainfall
Acid rain
Increasingly Acidic
Tomato
juice
Lemon juice
Stomach acid
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38. Acids
Any compound that gives off a hydrogen ion (H+) in a solution.
HCl
Stomach acid
Lemon juice
Tomato juice

39. Bases
Any compound that will produce hydroxide ions (OH-) in a solution.
Human blood
Sea water
Oven cleaner
Bleach
soap

40. Time to play…
Ph lab

41. Buffers
Facts
Most cells in animals must generally be kept at a pH level between 6.5 and 7.5
Human blood has a pH of 7.4
If the body’s pH level goes to high or too low then cells do not work
Maintaining pH levels is important for homeostasis
Large changes in pH are controlled by substances called buffers

42. Examples of buffer in the body’s cells
Carbonic Acid (H2CO3)
(H2CO3) → HCO3- + H+
Carbonic acid dissociates in water to form bicarbonate ion and H ions

43. Chemical Reactions
Everything that happens in an organism is based on chemical reactions
Definition: a chemical reaction is a process that changes one set of chemicals into another set of chemicals
Cellular respiration
Formation of Carbonic Acid from carbon dioxide and water

44. Mixture
2 or more elements or compounds that are physically mixed together but not chemically combined.
Salt & pepper
Earth’s atmosphere
Salad
soil

45. Solutions Evenly distributed throughout. Solvent; does the dissolving
Solute; gets dissolved
Water is the greatest solvent.

46. NaCI Solution
Cl-
Cl-
Na+
Na+
Water
Water

47. NaCI Solution
Cl-
Cl-
Na+
Na+
Water
Water

48. Suspension Unevenly distributed throughout. (settle out) Water & gas
Water & oil
Blood

49. 4 Organic Compounds Carbon Compounds Carbohydrates Lipids
include
Carbohydrates
Lipids
Nucleic acids
Proteins
that consist of
that consist of
that consist of
that consist of
Sugars and
starches
Fats and oils
Nucleotides
Amino Acids
which contain
which contain
which contain
which contain
Carbon,
hydrogen,
oxygen
Carbon,hydrogen,
oxygen, nitrogen,
phosphorus
hydrogen,oxygen,
nitrogen,

50. Organic Compounds
Organic compounds contains Carbon, Hydrogen and Oxygen

51. Carbohydrates Main source of energy Monosaccharide (simple sugar)
Glucose – produced by green plants.
Fructose – fruits, vegetables, honey.
Disaccharides (double sugar)
Lactose – mammals milk.
Sucrose – table sugar.
Polysaccharides (complex sugar)
Cellulose (plants)
Starch (plants)
Glycogen (animals)

53. Plants store carbohydrates as Starch
Glucose
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54. Animals store carbohydrates as Glycogen in the liver and muscles

55. Lipids Stored energy Fatty acids Saturated fatty acids – meat & dairy.
Unsaturated fatty acids – plants.
Phospholipids
Waxes
Oils
Steroids

56. Lipids What is it? Functions Fat, oils, and waxes
Lipid cells together are know as adipose tissue, hey look at that spare tire!
Adipose tissue acts to cushion vital organs
Once your body creates a fat cell, it is yours for life, you can never get rid of it!
Functions
Stores a huge amount of energy, even more than that carbohydrates
But it is used for emergency situations when you run out of carbohydrates

57. Types of lipids found in animals
HDL
Known as the “good” lipid
Found in vegetables, oils, and some nuts
Helps clear out LDL of you system
Exercise will increase the levels of HDL in an animals system
LDL
Triglycerides

58. Proteins Made up of Amino acids 20 different amino acids
Structural- cell, muscle, skin, organs.
Movement
Enzymes

59. Proteins Examples of proteins Facts Muscle, insulin, hair
Accounts for %50 of cells weight
Used for support, storage, transport defense, signaling other cells
Humans have 10s of thousands of different proteins
Are made of monomers called amino acids
There are 20 different amino acids

60. What makes a protein function
The order of the amino acids
Each protein has a specific order
The shape of a protein determines its function
Homeostasis: too much acid-proteins unfold. To high a temperature: proteins unfold, to cold: proteins cant function

66. 3-D Protein

67. Nucleic Acids Deoxyribonucleic Acid (DNA) Ribonucleic Acid (RNA)
Contains genetic information
Controls the production of proteins
Nucleotides
Phosphate
Sugar
base

71. Enzymes
Some reactions that are needed in life are too slow to happen by themselves.
To speed up these reactions cell in plants and animals produce catalysts.
A substance that speeds up chemical reactions
They work by lowering the activation energy
Enzymes are proteins that act as biological catalysts
Always end in ase
Lactase, carbonic anhydrase
Very specific

72. Catalyst
Substance that reduces the amount of energy for a reaction to occur.
Catalyst in cells are proteins called Enzymes.
The substance that the enzyme works on are called a substrate.
Enzymes are very selective.

73. Enzyme animation

74. Effect of Enzymes Reaction pathway without enzyme Activation energy
Section 2-4
Reaction pathway
without enzyme
Activation energy
without enzyme
Reactants
Activation
energy
with enzyme
Reaction pathway
with enzyme
Products
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75. Time to play…
Enzyme lab
Organic compounds lab