Chemistry of Biomolecules

1
Chemistry of Biomolecules
2

• Most biological compounds are ORGANIC compounds
  of CARBON
• The study of these compounds is ORGANIC CHEMISTRY.

3
Carbon!

• Why its cool, and what it can do

4
6 electrons 2 - 4
5
ORGANIC CONTAINING CARBON

• The fact that Carbon has 4 electrons in its outer
  valence level, means it can make four covalent
  bonds with other atoms.
• It can also do neat things like
• form long chains, branches, rings, and double
  bonds

6
(No Transcript)
7
Monomers Polymers when carbons get together

• Individual units called MONOMERS are linked
  together to form big molecules called POLYMERS.
• monomer monomer monomer
• Polymer

8
A polymer of glucose (sugar) units
9

• Very large polymers made from Carbon-based chains
  are called MACROMOLECULES
• Macro giant
• (so, giant molecule)

10
How do monomers come together to form a polymer?

• Dehydration Synthesis
• Chemical reaction where two monomers join
  together and release water.

11
How do polymers break down into monomers?

• Hydrolysis
• Chemical reaction in which water is added and
  splits a polymer back into monomers

12
Hydrolysis of a disaccharide
13
MACROMOLECULES come in different varieties

• 4 important groups
• Carbohydrates
• Proteins
• Lipids
• Nucleic Acids

14
What type of macromolecule is shown here?
15
Carbohydrates

• Monomer monosaccharide
• Ex glucose, fructose, galactose
• Function energy, structure
• Example Sugar, cellulose (crunchy part of
  plants), starch, glycogen (glucose storage in
  the liver)

16
Facts about carbs

• Carbohydrates include C. H, and O in a 121
  ratio, such as in glucose C6H12O6.
• They exist as rings with an integral Oxygen and
  many H and OH groups.
• The simplest are monosaccharides, such as
  glucose, fructose, or galactose.

17
Glucose C6H12O6 a monosaccharide
18
Disaccharides

• Disaccharides have two rings, such as sucrose
  which is table sugar.

19
Lactose milk sugar
20
Polysaccharides many monosaccharides linked
together, such as in glycogen, starch, and
cellulose
21
Types of polysaccharides

• a. Glycogen Animal glucose storage in
• the liver and muscles
• b. Starch Plant energy storage.
• c. Cellulose wood, plant material
• Most abundant carbohydrate

22
Glycogen in liver cells
23
Plant starch in potato cells
24
Cellulose fibers in plant cells

25
Models of carbohydrates
26
Test for Sugarsthe Benedicts Test
27
Test for starch - iodine
28
What type is shown here? (Okay, there are a few
hints.)
29
Proteins

• Monomer amino acid (20 of them)
• Functions
• Structure muscle proteins
• Fight disease - antibodies
• Control rates of reaction - enzymes
• Transport substances in out of the cell -
  hormones, channel proteins

30
An Amino Acid
31
The structure of an amino acid
AMINO GROUP
ACIDGROUP
The R groups is any atom or group of atoms. It
makes each amino acid unique.
32
Structure of an Amino Acid
33
There are 20 different amino acids with different
R groups.
34
(No Transcript)
35
Amino acids are held together by peptide bonds
36
Peptide Bond FormationNotice the loss of a water
molecule.
37
A Polypeptide is many amino acids linked
together. beginning of a protein
38
Proteins have complex shapes that determine their
function.
39
The levels of protein structure

• Primary chains of amino acids
• Secondary folds
• Tertiary compacting
• Quaternary two or
• more chains

40
What level is shown here in the protein insulin?
Quaternary Two chains
41
If the primary structure is disrupted,then the
protein may not be shaped correctly and will not
be able to function as in hemoglobin in the
disease sickle cell anemia.
42
Test for proteinthe Biuret test
43
What type of macromolecule is shown here?
44
Lipids

• Function
• Chemical messengers (steroids)
• Insulation and cushioning
• Long lasting energy source
• Examples
• Fats and oils
• Phospholipids (cell membrane fats)
• Steroids (cholesterol)
• composed of fatty acids on a glycerol backbone
• Are NOT SOLUBLE in water!

45
composed of fatty acids and a glycerol
backbone
ACID group
Joined to three fatty acid tails
Fatty acids have many C-H bonds - good energy
source.
46
When three fatty acids join to the glycerol
molecule, three water molecules are lost.
Fatty Acids
Glycerol
Lipids
47
To separate parts of the fat molecules, you have
to add 3 water molecules in a hydrolysis reaction
Hydrolysis of a triglyceride
48
Saturated fats have only C TO C single bonds in
their fatty acid tail.Unsaturated fats have
one or more C C double bonds in their fatty
acid tail.
49
Fats and Oils

• Saturated fatty acids (butter, fats) are solid at
  room temperature
• Unsaturated fatty acids (oils) are liquid at room
  temperature and better for you and your arteries.

50
(No Transcript)
51
Polyunsaturatedmore than one C-C double bond
52
Is there a shorter way to represent these BIG
molecules?
53
Omega end
Short-hand way to write a fatty acid. The end
away from the acid end is the Omega end.
54
An Omega 3 fatty acid
OMEGA END
55

• Omega 3 fatty acids are better for you than Omega
  6 ones.

56
Trans Fats are not good for you.
57
Food labels help you decide if the food you are
eating is healthy.
58

• Due to their chemical structure, lipids are not
  soluble in water.

59
Phospholipids used in cell membranesThey have
a phosphorus atom in their structure.
The Polar Part is attracted to water so
HYDROPHILIC
Tails are HYDROPHOBIC.
60
The Polar Part is attracted to water so
HYDROPHILIC
Tails are HYDROPHOBIC.
61
(No Transcript)
62
Another type of lipid that makes up cell
membranes is cholesterol. It is a steroid and
exists as fused rings.
63
Cell membranes and lipids
64
A test for fats is a greasy transparent spot on
paper.
65
Nucleic Acids

• Monomer nucleotide
• Function
• In heredity DNA makes up genes
• Direct production of proteins
• Examples DNA and RNA

66
Can you identify this type of macromolecule?
67
A nucleotide is made of a sugar, phosphate group,
and a Nitrogen base.
The Nitrogen Bases have Four different Ones.
68
DNAs main job

• To code for the amino acids that make a PROTEIN
• RNA helps.

69
So, hope you have it!Because this is a QUIZ!
70
1, How many bonds go to each Carbon?
71
2. Is this a monosaccharide, disaccharide, or
polysaccharide?
72
3. Is this fat saturated or unsaturated?
73
4. This is a phospholipid found in cell
membranes. Which part (color) is hydrophobic?
74
5. What is this a model of?