1. Biochemical Basis of Life

2. Atoms Atoms are the basic units of matter.
The atom is the smallest particle of a substance that still remains the properties of that substance.
Atoms are composed of protons, neutrons, and electrons.

3. Atoms (continued) Protons: positive charge Neutrons: no charge
Electrons: negative charge
Protons and neutrons have about the same mass and are found in the center of the atom, the nucleus.
Electrons are very light and in constant motion surrounding the nucleus.

4. Elements
A chemical element is a pure substance that consists entirely of one type of atom.
More than 100 are currently known to exists; however, only about 20 to 24 are commonly found in living organisms.

5. Symbols for Elements
Chemists use symbols of one or two letters to represent elements. The first letter is always capitalized. If there is a second letter, it is not capitalized.
C represents carbon.
Al represents aluminum.
Au represents gold. (The Latin name for gold is aurum.)

6. Compounds
A compound is a substance formed by the chemical combination of two or more elements in definite proportions.
The composition of compounds are represented by a kind of shorthand known as a chemical formula.
H20: 2 elements of hydrogen and 1 element of oxygen
The physical and chemical properties of a compound are usually very different from the individual elements.

7. Chemical Bonds
The atoms in compounds are held together by various types of chemical bonds.
Bond formation involves the electrons that surround each atomic nucleus. The tendency of elements to combine and form compounds depends on the number and the arrangement of electrons in their outermost energy level.
The main types of bonds are ionic and covalent bonds.

8. Inorganic Molecule Inorganic Molecules: Are not organic (non-living)
Most (but not all) do not include the element carbon
Examples: water (H2O), ammonia (NH3), table salt (NaCl), and carbon dioxide (CO2)

9. Ionic Bonds
An ionic bond is formed when one or more electrons are transferred (donated or accepted).
An atom that loses electrons becomes positively charged. An atoms that gains electrons becomes negatively charged. Atoms with a charge are called ions.
Ionic bonds form between sodium and chlorine to form table salt (NaCl).

10. Electrons Electrons have energy levels surrounding the nucleus.
1st energy level has 2 electrons
2nd energy level has 8 electrons
3rd energy level has 18 electrons
4th through 7th energy levels like bond in 8 or groups of 8 or have full electron shells. (An electron’s happy state is 8: octet rule)

11. Ionic Bonds
Protons Protons Protons Protons Electrons Electrons Electrons Electrons -18
Charge Charge Charge Charge

12. Covalent Bonds
A covalent bond is formed when electrons are shared by atoms.
When atoms of the same element join together, they also form a molecule.
Covalent bonds form between hydrogen and oxygen to form H2O, water.

13. What type of bond is the cartoon illustrating?

14. Answer
The cartoon is illustrating an ionic bond. An ionic bond is an electrical attraction between two oppositely charged atoms. The positively charged atoms are inside the classroom are attracted to the negatively charged atoms on the outside of the window.

15. Properties of Water
A water molecule (H20), is made up of three atoms: two hydrogen and one oxygen.
Water is one of the few compounds found in a liquid state over most of the surface of Earth. In its solid state, ice has a low density allowing objects to float.
Water is polar. The charges are unevenly distributed. The hydrogen end is positive and the oxygen end is negative.
Because water is a polar molecule, it is able to perform multiple hydrogen bonds, which account for many of water’s special properties.

16. Properties of Water
The attraction between a hydrogen atom on one water molecule and the oxygen atom on another water molecule is called a hydrogen bond.
Hydrogen bonds are not as strong as ionic or covalent bonds, and they can form in other compounds as well.

17. Properties of Water
High Heat Capacity is the amount of heat energy required to increase its temperature.
Adhesion is an attraction between molecules of different substances. Adhesion forms capillary action which give water the ability to climb structures.
(Ex. Water in the stem of plant stalks)
Cohesion is attraction between molecules of the same substance. Cohesion causes water molecules to be drawn together . This results in surface tension.

18. Properties of Water
Surface tension – cohesion of water with a film-like quality on the surface of a liquid
Capillary action – tendency of a liquid to draw up into a narrow tube due to the liquid’s properties of cohesion and adhesion

19. Solutions A solution is composed of two parts: solute and solvent.
- In a salt water solution, table salt is the solute – the substance that is dissolved.
- Water is the solvent – the substance in which the
solute dissolves.
Water is the universal solvent.
A homogenous mixture is a solution where the substance looks the same throughout .

20. Van der Waals
Van der Waals forces include attractions and repulsions between atoms, molecules, and surfaces, as well as other intermolecular forces. 
Geckos can stick to walls and ceilings because of Van der Waals forces.

21. Let’s Practice
Identify the property of water that best describes the following statements:
Water forms raindrops as is flows through the air. ________________
Fish and other aquatic life are able to survive in subzero temperatures. _______________
Water is able to ascend very tall trees. ______________
Many types of materials are able to be dissolved in water. _________________

22. Answers Water forms raindrops as is flows through the air. Cohesion
Fish and other aquatic life are able to survive in subzero temperatures. low density of ice
Water is able to ascend very tall trees. adhesion
Many types of materials are able to be dissolved in water. polarity

23. Acids and Bases
Some compounds break into ions when they dissolve in water.
An acid is any compound that forms hydrogen ions (H+) in a solution.
A base is a compound that produces hydroxide ions (OH-) in a solution.

24. pH
The pH scale is a measurement system used to indicate the concentration of H+ ions in a solution.
pH scale ranges from 0 to is neutral.
Solutions with a pH below 7 are called acidic because they have more H+ ions than OH- ions. The lower the pH, the greater the acidity.
Solutions with a pH above 7 are called basic because that have more OH- ions than H+ ions. The higher the pH, the more basic the solution.

25. Buffers
The pH of the fluids within most cells in the human body must generally be kept between 6.5 and 7.5 in order to maintain homeostasis. If the pH is lower or higher, it will affect chemical reactions that take place within the cells.
One of the ways that organisms control pH is through dissolved compounds called buffers, which are weak acids or weak bases that can react with strong acids or bases to prevent sharp, sudden changes in pH.

26. pH Scale

27. Practice #2 Use the diagram below to answer the following:
5. Which is more basic: blood or ammonia? _______ 6. What is the pH of drain cleaner? ____________ 7. Would a lemon have more hydrogen or hydroxide ions? _____________ 8. What is the pH of lemon?_______________ 9. Is water an acid, a base, or neutral? ___________

28. Answers
5. Which is more basic: blood or ammonia? ammonia 6. What is the pH of drain cleaner?14 7. Would a lemon have more hydrogen or hydroxide ions? hydrogen 8. What is the pH of lemon?2 9. Is water an acid, a base, or neutral? neutral

29. Let’s Practice - 3
10. John consumes large amounts of black coffee and tomato juice daily. Sometimes these fluids cause digestive discomforts, and he takes antacids to reduce the symptoms. Use your knowledge of acids, bases, and pH to explain why antacids reduce the symptoms.

30. Answer
Coffee and tomatoes are acidic fluids. Antacids are bases. A base reacts with an acid to form a less acidic product. Antacids help neutralize digestive juices by changing its pH.

31. Carbon Compounds
Biomolecule is an organic molecule produced by a living organism
Carbon can bond with many elements, including hydrogen, oxygen, phosphorus, sulfur, and nitrogen to form the molecules of life.
Carbon can share its electrons with other atoms to form up to four covalent bonds.
Carbon-carbon bonds can be single, double, or triple covalent bonds.
Chains of carbon atoms can even close up on themselves to form rings.

32. Macromolecules Polymer Train
Many of the molecules in living cells are very large and known as macromolecules.
Most macromolecules are formed by a process known as polymerization through which large compounds are built by joining smaller ones together.
The smaller units or monomers join together to form polymers.
Polymer Train
monomer + monomer + monomer + monomer

33. Polymers
Polymers are formed by dehydration synthesis or condensation reaction because water is given off every time a monomer is added to the chain.
Polymers are broken apart by hydrolysis because water is added to break off monomers from the chain.

34. Types of Macromolecules
Carbohydrates
Lipids
Proteins
Nucleic Acids

35. Macromolecules: Carbohydrates
Type
Structures
Monomers
Function
Sugar, starches, and cellulose
Carbon:Hydrogen:Oxygen
Glucose
Living things use carbohydrates as their main source of energy.
Monosaccharide
1:2:1 ratio
C6H12O6
Disaccharides
Polysaccharides

36. Types of Carbohydrates
Monosaccharide: one simple sugar. Examples are glucose (plant sugar), fructose(fruit sugar), galactose(milk sugar)
The formula for glucose is C6H12O6. Plants produce glucose during photosynthesis
Disaccharide: two simple sugars joined by a saccharide bond. Examples are sucrose(table sugar made of glucose bonded to fructose), lactose(milk sugar), and maltose (malt beverage sugar)

37. Types of Carbohydrates
Polysaccharide: many sugars; three or more monosaccharides combined.
Examples:
starch (stores glucose in roots of plants)
cellulose(cell walls to support plant)
chitin (shell of crustaceans and insects or cell wall for fungi)
glycogen (energy storage for glucose in liver cells and breaks
down by hydrolysis)

38. Isomers Isomers have the same elements, but are arranged differently.
An example of an isomer is glucose, fructose, and galactose.

39. Macromolecules: Lipids
Type
Structure
Monomer
Function
Fats, Oils, Waxes
Carbon, Hydrogen, and Oxygen
3 Fatty Acids and Glycerol
Lipids form part of biological membranes, store energy, help insulate the body, and cushion and protect organs.
NOT in the same 1:2:1 ratio as carbohydrates

40. Lipids Lipids are made of glycerol and three fatty acids.
Lipids contain fewer oxygen than carbohydrates
Lipids are used for protection, cushion, structure, insulation, and long-term energy storage.
Main types of lipids are fat, phospholipids, steroids, and wax.

41. Phospholipids
Fatty acids: an organic acid that contains a long chain of hydrocarbons (carbon atoms bonded to other carbon atoms and hydrogen atoms)
Phospholipids make up cell membranes.
They are fatty acids that contain phosphorus.

42. 2 Types of Fats
Saturated: solid at room temperature, example animal fats (butter, shortening, lard)
Unsaturated: liquids at room temperature and can be monounsaturated or polyunsaturated
Monounsaturated: a fat that has one double carbon-to-carbon bond examples: nuts, seeds, avocados, olive oil, peanut oil
Polyunsaturated: fats that contain fatty acids with double carbon-to-carbon bonds; examples: vegetable oils cold water fish

43. Other Types of Lipids
Steroid: a type of lipid that can be present in cell membranes or can make up certain hormones which are chemical messengers or regulators.
Wax: a type of lipid that is used to waterproof leaves, skins, and feathers.

44. Macromolecules: Proteins
Type
Structure
Monomer
Function
Antibodies, Muscles, Enzymes, and Hair.
Carbon, Hydrogen, Oxygen, and Nitrogen
Amino Acids (20)
Proteins control rate of reactions, regulate cell processes, form cellular structures, and fight diseases.

45. Proteins
Amino acids are organic molecules that are building blocks of protein
Nitrogen is an element found in amino acids and proteins but not carbohydrates
The arrangement, number, and type of amino acids are important. Any change in a protein’s shape determines its function.
Proteins are receptors that detect chemical signals so cells can respond to stimuli and chemical messengers by sending signals for changes in cell activities.
Thyroid is a stimulating hormone which maintains body metabolism (energy).
They provide storage for elements such as iron.

46. Proteins
Proteins are composed of carbon, hydrogen, oxygen, and nitrogen with sulfur and two amino acids
The building blocks of protein are amino acids held together by a peptide bond, a chain of amino acids.
Examples of proteins are antibodies (protect against disease), main structural component of muscles, skin, bone, hair, and enzymes.

47. Chemical Reactions
Chemical reaction is a process that changes one set of chemicals into another set of chemicals.
Reactants are substances that go into a chemical reaction.
Products are substances that result from a chemical reaction.
Reactants and products are separated in a chemical reaction by a yields sign .

48. Enzymes
Activation energy is the term used to describe the energy needed to get a reaction started. A catalyst is a substance that accelerates the rate of a chemical reaction.
Enzymes are proteins that act as biological catalysts. Enzymes do not cause reactions to happen. They speed up chemical reactions that take place in cells.
Enzymes act by lowering activation energies, which has a dramatic effect on how quickly reactions are completed. Without enzymes the reactions of the cells would proceed very slowly.
Enzymes are never used up in the reaction. They can be used over and over again.
Enzymes get their names from the substances they act on and on the action of the enzyme and end in “ase.”
Examples: Lipase – breaks down a lipid; protease breaks down protein; amylase breaks down carbohydrates; lactase breaks down lactose

49. How Enzymes Work
Enzymes are very specific, generally catalyzing only one chemical reaction.
The reactants of the enzyme-catalyzed reactions are known as substrates.
The substrates bind to a site on the enzyme called the active site.
The active site and the substrate have complementary shapes.
The fit is so precise the active site and substrate are often compared to a lock and key.

51. Enzyme Regulation
Concentration- the number of particles either substrate or enzyme can cause a reaction to speed up until it reaches a saturation point in which all enzyme or substrate molecules are exchanged in reaction.
Temperature – Enzymes produced by the human cells generally work best at temperatures close to 37°C, the normal temperature of the human body.
pH – Enzymes work best at certain pH values. For example, the stomach enzyme pepsin, which begins protein digestion, works best under acidic conditions.
Salinity – refers to the concentration of salt in a solution or the number of ions in a solution.
Regulatory Molecules- The activities of most enzymes are regulated by molecules that carry certain chemical signals within cells, switching enzymes “on” or “off” as needed.

52. Feedback Loops
A series of reactions that takes place in a cell is a metabolic pathway. Enzymes are used at each step in a series of reactions until the desired final substrate is created. Once the final substrate is created, it often inhibits the enzyme at the beginning of the metabolic pathway so production stops or slows down. This type of feedback is called a negative feedback loop.

53. Let’s Practice – 4 Label as enzyme, active site, products, substrate (reactants) , and enzyme-substrate complex (one is used twice). #11

54. Answers #11

55. Review
12. The effect of pH on a certain enzyme is shown in the graph below:
At what pH would the enzyme be most effective?
A. Above 10 B. between 8 and 10
C. Between 5 and 7 D. below 5

56. Review
12. The effect of pH on a certain enzyme is shown in the graph below:
At what pH would the enzyme be most effective?
A. Above 10 B. between 8 and 10
C. Between 5 and 7 D. below 5

57. Review
13. An enzyme and four different molecules are shown in the diagram below: The enzyme would most likely affect reactions involving: A. molecule A, only B. molecule D, only C. molecules B and D D. molecules A and C

58. Review
13. An enzyme and four different molecules are shown in the diagram below:
The enzyme would most likely affect reactions involving:
A. molecule A, only B. molecule D, only
C. molecules B and D D. molecules A and C

59. Review
14. Ice floats on a lake. This characteristic of water is responsible for A. Suffocation of aquatic organisms B. Mixing a lake’s thermal layers C. Preventing a lake from freezing solid D. Altering migration patterns of fish

60. Review
14. Ice floats on a lake. This characteristic of water is responsible for
A. Suffocation of aquatic organisms
B. Mixing a lake’s thermal layers
C. Preventing a lake from freezing solid
(High Heat Capacity is the amount of heat energy required to increase its temperature.)
D. Altering migration patterns of fish

61. Review
15. Proteins are formed from monomers (subunits) called: A. Nucleic acids B. Fatty acids C. Nucleotides D. Amino acids

62. Review 15. Proteins are formed from monomers (subunits) called:
A. Nucleic acids (it’s a type of macromolecule)
B. Fatty acids (monomers of lipids)
C. Nucleotides (monomers for nucleic acids)
D. Amino acids

63. Macromolecules: Nucleic Acids
Type
Structure
Monomer
Function
DNA
RNA
Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus
Nucleotides
Nucleic acids store and transmit genetic information.

64. Nucleic Acids
Nucleic acids are used for controlling cellular activities and making protein (genes)
Nucleic acids are made of:
a simple sugar: deoxyribose for DNA and ribose for RNA
phosphate group
nitrogen base: adenine, cytosine, guanine, and thymine for DNA and adenine, cytosine, guanine, and uracil for RNA
DNA stores and transmits genetic information. The main function of RNA is protein synthesis, making proteins.

65. Organic Substances of the Body
Organic Compound
(Polymer)
Elements
Building Blocks
(monomer)
Carbohydrates
C, H, and O
(H:O ratio of 2:1)
Simple sugars (monosaccharaides)
Lipids
C, H and O
Glycerol and Fatty Acids
Proteins
C, H, O, and N
Amino Acids
Nucleic Acids (DNA and RNA)
C, H, O, N and P
Nucleotides

66. Let’s Practice -5 Matching #16

67. Answer for Practice -5 #16

68. Review
17. Which of the following macromolecules are a prominent part of animal tissues that function in insulation, helping animals to conserve heat? A. Carbohydrates B. Lipids C. Proteins D. Nucleic Acids

69. Review
17. Which of the following macromolecules are a prominent part of animal tissues that function in insulation, helping animals to conserve heat? A. Carbohydrates B. Lipids C. Proteins D. Nucleic Acids