1. What are organic molecules?
Molecules of Life
What are organic molecules?
Compounds that contain carbon
What are biological molecules?
Nucleic Acids
Carbohydrates
Lipids
Proteins

2. Organic Molecules What is a cell made up of mostly?
Mostly water, but what else?
Carbon based molecules
Why is carbon so significant for these molecules?

3. Each carbon acts as an ‘intersection’
With 4 different branch points
Creates endless variety of (organic) carbon molecules
Vary in length

4. Diversity of Carbon-Based Molecules
Different location of double bonds
Unbranched or branched
Rings

5. Methane ……….. Is a hydrocarbon What is a hydrocarbon?
& Hydrogen
Methane is the simplest

6. Functional Groups
Groups of atoms known as functional groups can give special properties on carbon-based molecules.
Carbon is a central element to life because most biological molecules are built on a carbon framework.

7. Functional Groups
For example, the addition of an –OH group to a hydrocarbon molecule always results in the formation of an alcohol.

8. Functional Groups

9. Making Polymers Dehydration* Reaction - links molecules together
A covalent bond forms between molecules and water is removed
Reaction by which monomers are joined to form larger molecules
Examples:
*Also called a condensation reaction

11. Breaking Polymers Hydrolysis reaction – breaks down larger molecules
Water is added to a larger molecule to split off a smaller molecule.
Reaction involves breaking a covalent bond by adding water
Reverse of a dehydration reaction

13. Biological Molecules Food ‘Carbs’ Structural Sugar Storage Glucose
Enzymes
Glycogen
Antibodies
Cellulose
Oils
Fatty acids
(sat & unsat)
DNA
RNA
Butter

14. Carbohydrates
Carbohydrates are formed from the building blocks or monomers of simple sugars, such as glucose.
These monomers can be linked to form larger carbohydrate polymers, which are known as polysaccharides or complex carbohydrates.

15. Carbohydrates What type of sugar is found in the following?
Small (simple) sugar molecules
Examples?
Monosaccharides
Glucose
Fructose
Disaccharides
Lactose
Sucrose
Long starch molecules in pasta, potatoes
Examples?
Polysaccharides
Starch
Cellulose
These are our primary sources of dietary energy
In plants, carbs used as building material

16. Monosaccharides What type of sugar is found a sports drink?
Glucose
What type of sugar is found in fruit?
Fructose

17. What about honey? Its really sweet? Why?
It contains both glucose and fructose

18. Glucose and Fructose Have the same formula… C6H12O6
Why are they ‘different’?
They are isomers

19. Form rings in aqueous solutions
Which sugar is this?
Glucose

20. Disaccharides Are ‘double sugars’ What are they constructed from?
2 monosaccharides

21. Disaccharides Maltose: glucose and glucose Lactose: galactose and
Sucrose:
glucose and
fructose

22. Lactose, another disaccharide
Some people have trouble digesting lactose
Its a condition called lactose intolerance
Missing gene for lactase enzyme

23. Sucrose Common table sugar Sugar cane Roots of sugar beets
The most common disaccharide is sucrose, what do you know it as?
Common table sugar
What plants do we use to extract table sugar?
Sugar cane
Roots of sugar beets

24. Polysaccharides Are long chains of sugar units Starch Glycogen
(polymers)
(monosaccharides)
What are some polysaccharides?
Starch
Glycogen
Cellulose

25. Starch Glycogen Cellulose
Potatoes and grains are major sources of starch in the human diet
Glycogen
Liver, muscle cells break down glycogen to release glucose when needed for energy
Cellulose
Structural component, dietary fiber

26. Complex Carbohydrates
Four polysaccharides are critical in the living world:
starch
glycogen
cellulose
chitin

27. Four Complex Carbohydrates
Potato
(b)
Liver
(c)
Algae
(d)
Tick
Starch
Glycogen
Cellulose
Chitin

28. Biological Macromolecule: Carbohydrates
Function:
Monomer:
Dietary energy
Storage
Plant structure
Examples:
Monosaccharides
(simple sugars)
(glucose, fructose)
Disaccharides
(double sugars)
(maltose, lactose, sucrose)
Polysaccharides
(long polymers)
(starch, glycogen, cellulose)

29. Starch is the nutrient storage form of carbohydrates in plants.
Glycogen is the nutrient storage form of carbohydrates in animals.

30. Lipids Butter, lard, margarine, and salad oil
Do these lipids mix well with water?
Lipids do not possess the monomers-to-polymers structure
seen in other biological molecules; no one structural element
is common to all lipids.
Among the most important lipids are the triglycerides,
composed of a glyceride and three fatty acids.
Most of the fats that human beings consume are triglycerides.

31. Lipids This diverse group of molecules includes? Fatty acids Steroids
(energy storage, cushioning, insulation)
A biological compound consisting of three fatty acids linked to one glycerol molecule
Steroids
(cholesterol, in membranes)
Characterized by a carbon skeleton consisting of four rings with various functional groups attached

32. Fatty Acids Technically called? triglycerides A fat molecule: Glycerol
‘saturated’
‘unsaturated’
Double bond ‘unsaturated”

33. Unsaturated fatty acids
(plant oils)
Have less than the maximum number of hydrogens bonded to the carbons
Saturated fatty acids
(butter)
Have the maximum number of hydrogens bonded to the carbons

34. Double Bonds
What is the significance of the number of double bonds in the hydrocarbon tails?
Unsaturated fats tend to be liquids at room temperature
Example?
vegetable oils
Impact on health?
unsaturated fats are safer
Saturated fats are solid at room temperature
Example?
butter and lard
Impact on health?
Saturated fats in the diet can lead to heart disease

35. Steroids How does the structure differ from fatty acids?
Ring structure, various functional groups
How does the function differ from fatty acids?
Functional groups affect function
causes differences between the hormones estrogen and testosterone
Example?
(anatomical and physical development)
cholesterol in membranes

36. Steroids (a) Four-ring steroid structure (b)
Side chains make each steroid unique
testosterone
estrogen
cholesterol

37. Phospholipids
A third class of lipids is the phospholipids, each of which is composed of two fatty acids, glycerol, and a phosphate group.
The material forming the outer membrane of cells is largely composed of phospholipids.

38. Waxes
A fourth class of lipids is the waxes, each of which is composed of a single fatty acid linked to a long-chain alcohol.
Waxes have an important “sealing” function in the living world.
Almost all plant surfaces exposed to air, for example, have a protective covering made largely of wax.

39. Biological Macromolecule: Lipids
Function:
Monomer:
Long term energy storage
Hormones
Examples:
Fats, oils
(triglycerides)
(butter, lard, margarine, salad ols)
Steroids
(lipid rings)
(cholesterol, hormones)

40. Proteins What is a protein? Proteins are an extremely diverse group of
biological molecules composed of the monomers
called amino acids.
Constructed from a set of 20 different monomers

41. Proteins
Sequences of amino acids are strung together to produce polypeptide chains, which then fold up into working proteins.
Important groups of proteins include enzymes, which hasten chemical reactions, and structural proteins, which make up such structures as hair.

42. Types of Protein

43. The Monomers What does each amino acid monomer consist of?
Amino group
Carboxyl group
A central carbon atom
Bonded to four covalent partners
Each side group is unique
Identifies each amino acid’s characteristics

44. Examples of 2 different amino acids and their side groups

45. Beginnings of a Protein
The linkage of several amino acids . . .
ala
gln
ile
ala
gln
ile
A typical protein would
consist of hundreds of
amino acids
. . . produces a polypeptide chain like this:

46. Structure Proteins are complex! Primary Secondary Tertiary Quaternary
To simplify, we’ll describe them in terms of 4 levels of structure:
Primary
a particular # and sequence of amino acids
Secondary
turns and folds, alpha helix, pleated sheet
Tertiary
irregular loops and folds, 3-D shape
Quaternary
2 or more polypeptides combined

47. Levels of Protein Structure
Four Levels of Structure In Proteins
(a)
Primary structure
The primary structure of any
protein is simply its sequence
of amino acids. This sequence
determines everything else
about the protein’s final shape.
amino acid sequence
(b)
Secondary structure
Structural motifs, such as
the corkscrew-like alpha
helix, beta pleated sheets,
and the less organized
“random coils” are parts
of many polypeptide
chains, forming their
secondary structure.
alpha helix
random coil
beta pleated sheet
(c)
Tertiary structure
These motifs may persist
through a set of larger-scale
turns that make up the
tertiary structure of the
molecule
folded polypeptide
chain
(d)
Quaternary structure
Several polypeptide chains
may be linked together in a
given protein, in this case
hemoglobin, with their
configuration forming its
quaternary structure.
two or more
polypeptide chains

48. Biological Macromolecule: Proteins
Monomer:
Function:
Amino group
Carboxyl group
Many!
Change rate of reaction
Carry molecules
Cell communication
Examples:
Enzyme
(lactase)
Transport
(hemoglobin)
= 20 amino acids
Defense
(antibodies)

49. Biological Molecules

50. Nucleic Acids What are nucleic acids?
The cells information storage molecules
There are two types of nucleic acids
DNA, deoxyribonucleic acid
RNA, ribonucleic acid
These ‘work together’ to synthesize protein

51. Synthesizing Protein What does DNA do?
It carries instructions for building all the proteins

52. What does DNA do?
Information in DNA is transcribed into RNA

53. What does RNA do?
RNA acts as an intermediary in the protein-making process
DNA
RNA
Protein

54. What else does RNA do?
RNA then translates the (transcribed) information into the primary structure of proteins
What is the primary structure of proteins?

56. What does protein do?
Proteins carry out cell activities

57. Structure What is the structure of nucleic acids?
They are polymers of nucleotides
What do the nucleotides contain?
Phosphate group
Nitrogen base
Sugar
(Deoxyribose)

58. What do DNA nucleotides contain?
Each DNA nucleotide has one of the following bases: 2 1
Adenine (A)
Thymine (T)
Cytosine (C) 4 3
Guanine (G)
Which one is which?
Match the numbers to the base

59. Polymers of nucleotides
Linked into long chains
Nucleotide
Called polynucleotides or DNA strands
A sugar-phosphate backbone joins them together
Bases
Activity: Nucleic Acid Structure

60. 2 DNA strands form helix How does this happen? A always binds with T
Via complementary binding
(and hydrogen bonding)
A always binds with T
C always binds with G

61. RNA, different from DNA
It has the base uracil (U) instead of thymine (T) in DNA
The RNA sugar has 2 OH groups vs 1 in DNA
(Ribose vs deoxyribose)

62. Biological Macromolecule: Nucleic Acids
Monomer:
Function:
Information storage
Phosphate
Examples:
DNA
Sugar
Base
RNA
Could this be a monomer for RNA?