Agenda: Day 2 Macromolecules

1
Welcome

• Agenda Day 2 Macromolecules
• Review Macromolecule I.D.
• Notes Proteins DNA
• Lab Modeling
• Chapter 5 Study Guide
• Hmwk
• Quiz Chapter 5 Modeling Lab

2
What is trans fat? In order to understand the
nature of and secret behind trans fat, it is
necessary to explain what fatty acids are. Fatty
acids can be described as chains of carbon which
are able to combine with other molecules. These
acid chains vary in length and may be either
saturated or unsaturated. Saturated fatty acids
have adequate hydrogens and therefore a straight
configuration which allow them to pack into a
solid crystal at ambient temperatures. On the
other hand, unsaturated fatty acids are missing
adequate hydrogens, so rather than solidifying at
ambient temperatures, a liquid oil is produced.
Unsaturated fatty acids are labeled either
monounsaturated or polyunsaturated depending upon
the number of hydrogens which are missing.
Polyunsaturated fatty acids lack the greatest
number of hydrogens making it the most unstable.
Trans fat is monounsaturated or polyunsaturated
fat which is altered by partial hydrogenation.
This process of partial hydrogenation forces the
oils which are naturally liquid at room
temperature to become solid, therefore modifying
the fat so it is more similar to saturated fat.
While trans fatty acids are considered
unsaturated by chemical definition, the
transformation is so severe that trans fat can
not be legally labeled as monounsaturated or
polyunsaturated fat on packages.
3
(No Transcript)
4
(No Transcript)
5
(No Transcript)
6
(No Transcript)
7
(No Transcript)
8
(No Transcript)
9
Proteins Functions

• Structural Collagen and elastin (animal
  tissues) keratin (hair, horns, feathers)
• Storage Store A.A. Ovalbumin is the protein
  of egg white used for the developing embryo.
  Casein, the protein of milk, is the major source
  of amino acids for baby mammals

10
Protein Functions

• Transport Hemoglobin transports oxygen from
  lungs to body in vertebrates
• Hormonal - Insulin secreted by pancreas
  regulates the concentration of sugar in the blood
  of vertebrates.
• Receptor Sodium-Potassium Pump regulate
  change in voltage across cell membranes allowing
  nerve impulses

11
Protein Functions

• Contractile Actin and myosin movement of
  muscles
• Defensive Antibodies combat bacteria and
  viruses
• Enzymes Amylase digests starch in the mouth

12
Proteins

• Proteins make up 50 of the dry weight of cells
• DNA codes the number and order of amino acids in
  a protein
• 20 known amino acids humans have 10s of
  thousands of diff proteins
• Unique conformation (3-D) shape
• Also called Polypeptides

13
Polypeptide a polymer of amino acids
R-Groups side chains can be electrically
charged (acids and basic), polar, or non polar.
14
Peptide bonds are formed through condensation
reactions.
15
Protein Structure

• A protein is specifically twisted, folded, and
  coiled into a unique shape.
• The shape is determined by the amino acid
  sequence.
• A proteins specific shape determines how it
  functions.
• In almost every case, the function of a protein
  depends on its ability to recognize and bind to
  some other molecule.

16
Examples

• An antibody binds to a particular forein
  substance that has invaded the body.
• An enzyme recognizes and binds to its substrate.
• Neurotransmitters secreted by a nerve cell signal
  another nerve cell by binding to receptors on
  that cell.

17
Primary Structure
The unique amino acid sequence.
18
Secondary Structure
Proteins have segments of their chain repeatedly
coiled or folded in patterns caused by hydrogen
bonds forming at regular intervals along the
polypeptide backbone. The nitrogen and oxygen
atoms in the backbone have weak negative charges
due to elctornegativity.
19
(No Transcript)
20
Tertiary Structure

• Irregular contortions from bonding between side
  chains of the various amino acids include
  hydrophobic interactions, disulfide bridges,
  hydrogen bonds, van der Waals, ionic bonds

21
Quaternary Structure

• The shape that results from the combination of
  more than one polypeptide chain ie. hemoglobin

22
Protein Shape can be altered

• Physical and Chemical Environment pH, salt
  concentration, temperature can cause a protein to
  change or denature protein loses its ability to
  function or decreases in its efficiency
• Chemical can change hydrophobic/philic shapes,
  disrupt the hydrogen bonds, ionic bonds, and
  disulfide bridges
• Heat can agitate the chain enough to overpower
  the weak interactions that stabilize conformation
  (cooking an egg)

23
Central Dogma

• DNA ---?RNA---?Protein

24
Nucleic Acids

• Deoxyribonucleic Acid (DNA) stores hereditary
  information
• Ribonucleic Acid (RNA) Stores and Transmits
  hereditary information
• Polymer of nucleotides

25
(No Transcript)
26
Nitrogen bases