Download The stuff of life?

Reading notes quiz#1, answer 4 of 5:
1.
2.
3.
4.
5.
does irradiating food add radiation to food? Explain
Describe the “octet rule”
What are the two types of chemical bonds
List at least 3 important properties of water
Biological molecules are grouped into four categories; list at
least 3 of these four.
Reading Notes Quiz#2:
Answer 3 of these 4 questions
1.
Biological molecules are grouped into four categories. List 3 of these 4.
2.
How do perms and relaxers work on hair?
3.
Describe the difference between a monomer and a polymer; give an example of a
monomer and a polymer (your example does not have to be a biomolecule).
4.
Like all lipids, a triglyceride is insoluble in water because it lacks many fill in the blank
functional groups. Triglycerides are used for fill in the blank and are made from two
subunits, a single molecule of fill in the blank plus three molecules of fill in the blank.
Hydrophobic
Hydrophilic
Fatty acids
Glycerol
Amino acid
Glycogen
Long-term energy storage
Quick and ready source of energy
Storing genetic information
Making a phospholipid membrane
What did this little piggy build
his house with?
(why does he build it with that that stuff, and
how does he build it?)
What do you get if you crack
open a cell?
What: You are what you eat!
the four classes of biomolecules
Lipids (fat)
Nucleic acid (DNA, RNA)
Protein (amino acid)
Carbohydrates (sugars)
Why build a cell with these materials?
What:
Lipids (fat)
Why (what is used for?):
store energy (fats and oils)
build cell membranes
(cholesterol & phospholipids)
cell to cell signaling (steroids)
Sugar (carbohydrates)
build cell structures (cellulose),
quick energy (glucose)
Protein
build cell structures (microtubules)
build cellular machines (enzymes)
Nucleic acid
store genetic information (DNA)
How do you build a cell:
Biomolecules are built using a
carbon scaffold + functional groups
Carbon scaffold (C and H)
Functional groups (O, N, P, S)
Analogy:
train cars
Analogy:
Different cargo in each train car
string of Christmas lights
Different colored light bulbs
monomer + monomer + monomer + monomer = polymer
“Food” is a polymer, you tear it down into monomers a rebuild polymers
Analogy: tear down a house into 2x4’s, bricks, windows, and rebuild
Biomolecule #1
Lipids - water insoluble hydrocarbons (C + H):
triglycerides (fats and oils)
phospholipids
cholesterol / steroids
What’s their structure? What are they made from?
What’s their function?
One type of lipid:
Triglycerides (fats and oils)
glycerol + fatty acid
(sugar alcohol) + (hydrocarbon)
Why are hydrocarbons (like fatty acids)
insoluble in water?
WHAT IS A TRIGLYCERIDE USED FOR?
Different types of fatty acids:
Saturated: all bonds between carbon are single bonds
Unsaturated: some double bonds between carbons (therefore less Hydrogens)
cis vs trans affects there physical property
Page 43, fig 3.13
Another type of lipid:
Phospholipids
Phospholipids - p 44, fig 3.14
how are these different from triglycerides (fats and oils)?
(what are they made from?)
What’s their function?
Another type of lipid:
cholesterol & steroids
cholesterol & steroids - p 44, fig 3.15
how are these different from phospholipids and triglycerides?
What are they made from?
how are they similar?
What’s their function?
Biomolecule #1
Lipids - water insoluble hydrocarbons (C + H):
triglycerides (fats and oils)
long term energy storage
phospholipids
build cell membranes
cholesterol / steroids
building cell membranes &
signaling between cells
Lipids are insoluble in water because they are built from hydrocarbons,
and hydrocarbons are hydrophobic because they do not have any
functional groups that form hydrogen bonds with water.
Why is a water-insoluble molecule good for: storing energy, or
building cell membranes, or
signaling between cells?
Biomolecule #2
Carbohydrates (sugars) - Carbon + H2O:
monomers:
glucose, fructose, galactose
glycerol
ribose, deoxyribose
polymers:
Disaccharides (lactose, maltose)
starch
glycogen
Cellulose
Chitin
Carbohydrates monomers
carbohydrates polymers: various uses
starch, glycogen, cellulose
chitin (glucose + NH2, amino functional group
Biomolecule #2
Carbohydrates (sugars) - Carbon + H2O:
monomers:
glucose, fructose, galactose
glycerol
ribose, deoxyribose
function:
quick energy source
build triglycerides
build DNA, and RNA
polymers:
Disaccharides (lactose, maltose)
starch
glycogen
Cellulose
Chitin
function:
quick energy source
energy storage (plants)
energy storage (muscle)
build structures
build structures
Biomolecule #3
Proteins - modified carbon skeleton backbone:
backbone is amino + carbon + carboxylic acid,
plus many diverse functional groups
monomers:
amino acids
polymers: peptides/proteins
enzymes
Microtubules
Hemoglobin
Membrane proteins
Protein monomer is amino acid.
amino acids have modified carbon skeleton backbone:
amino + carbon + carboxylic acid,
plus many diverse functional groups
Amino Acid Functional Groups:
Proteins are the most versatile biomolecules because they are made from chemically
diverse monomers (amino acids with many different functional groups)
A protein (or peptide) is a polymer made from amino acids
Biomolecule #3
Proteins …but what does a protein do?
Just about everything!
polymers: peptides/proteins
enzymes
Microtubules
Hemoglobin
Membrane proteins
function:
“machine” / metabolism
used to build structures
used to transport other molecules
selective doorway into cell
What’s an enzyme?
What do I mean by “cellular machine”?
Enzymes are “machines” that enable certain bonds to form
or break faster than they would without the enzyme
How do machines work?
Shape determines function
Cup
Spoon
Hammer
knife
How does a Protein
do its function?
It folds into a
particular shape.
Primary structure:
String of amino acids
Secondary structure:
Backbone H-bonds
with self, making
helix or sheet
Tertiary structure:
Functional groups
determines shape
shape determines
function/activity
ADH (Alcohol DeHydrogenase)
protein structure
QuickTime™ and a
decompressor
are needed to see this picture.
Proteins can unfold (denature)
Too hot
Too acidic or too basic
Biomolecule #4:
Nucleic acids
nitrogen-containing “base”
+ sugar (ribose or deoxyribose)
+ phosphate
Monomer (nucleotide bases):
A (Adenine)
T (Thymine) and U (Uracil)
G (Guanine)
C (Cytosine)
function:
energy “currency”
Polymer:
DNA
RNA
function:
store genetic information
“translate” from DNA to protein
Nucleic acid monomers (nitrogen-containing “base”+ sugar + phosphate)
and polymers (polynucleotide, example: DNA, RNA)
How does DNA store information?
RNA “translates” information
stored in DNA into a protein that
can actually do something
(enzyme, structural scaffold, etc)
Chemical Nature of DNA:
good for storing genetic information
-
O
P
O
H
G
O
N
O
N
O
-
O
R
O T/U
charged
phosphodiester
O
l inkages
-
N
H
O
H
O
H
N
O
N
H
N
P
O
A
R
N
H
X
N
C
N
O
X
O
O
R
N
H
N
N
A
O
O
N
N H
N
N
polyanionic - prevent folding,
therefore structure not
changed by encoded
information (imagine if the
property of the message you wrote on
paper changed the physical properties of
the paper/info)
-
O
R
H
O
H N
N
R
T/U
P
O
X
nucleobase pairs
O
N
O
O
O
P
N
N
H
O
sugar
H
O
O
P
O
OO
P
O
N
O
G
O
H
-
O
N
O
O
N
N
N
O
O
O
P
O
-
N
DNA stores information well:
C
O
O
O
H
H
X
P
N
N
O
O
H N
O
O
O
-
Repeating charge
does not fold
easy to copy because of
double helix with base pairing
(like shaking hands)
stable
Chemical Nature of Protein:
good for building structures and catalyzing chemical reactions
direction of polypeptide chai n
H
Repeating dipole can fold = conformation
..
..
O
R H
H
N
O
R H
N
N
H
..
H
O
H
O
..
..
RH
HR
O
RH
..
HR
N
O
H
N
N
N
H
+
+
R2
R4
+
+
-
R3
R5
+
+
R6
+
-
N
H R
O
H
H R
..
O
+
-
R1
..
direction of polypeptide chai n
Amino acids contain chemical functionality
that are primarily responsible for catalysis
Hydrogen bonds holding strands together
R = aminoacids
Proteins are made of 20 amino acids, offering many different chemical
functionalities (positive and negative charges, hydrophobic, base, thiol)
Therefore proteins can fold into many shapes, and their physical propeties
(function) can change dramatically
Step back and wonder
Why are there 4 nucleotides in DNA
Why those particular 4 nucleotides?
Why 20 amino acids?
Why those particular 20 amino acids?
Why is there RNA?
Why does RNA use AGCU and DNA use AGCT?
Does life have to use DNA, RNA and protein?