Download Lecture 3 (BY 14)

Molecules of Life
Chapter 3
_________ Compounds
Hydrogen and other elements
covalently bonded to______
•
•
•
•
Carbohydrates
Lipids
Proteins
Nucleic Acids
Bonding Arrangements
• Carbon atoms can
form _____ or
_____
• Other atoms project
from the carbon
backbone
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______________ ________
• Atoms or clusters of atoms that are
covalently bonded to carbon backbone
• Give organic compounds their different
properties
Examples of Functional
Groups
Hydroxyl group
- OH
Amino group
- NH3+
Carboxyl group
- COOH
Phosphate group
- PO3-
Dehydration synthesis
• Form polymers from subunits
• Enzymes remove -OH from one
molecule, H from another, form bond
between two molecules
• Discarded atoms can join to form _____
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Condensation
____________
• Breaks polymers into smaller units
• Enzymes split molecules into two or
more parts
• An -OH group and an H atom derived
from water are attached at exposed
sites
Hydrolysis
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Carbohydrates
________________
(simple sugars)
Oligosaccharides
(short-chain carbohydrates)
__________________
(complex carbohydrates)
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Monosaccharides
• Simplest ___________
• Most are sweet tasting, water soluble
• Most have 5- or 6-carbon backbone
Glucose (6 C)
Fructose (6 C)
Ribose (5 C)
Deoxyribose (5 C)
Two Monosaccharides
glucose
fructose
Disaccharides
• Type of
oligosaccharide
• Two
monosaccharides
covalently bonded
• Formed by
• _____________
___________
glucose
fructose
+ H2O
sucrose
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Polysaccharides
• Straight or branched chains of many
sugar monomers
• Most common are composed entirely of
glucose
– Cellulose
– ______
– Glycogen
Glycogen
• Sugar storage form in _______
• Large stores in ______ and
_______ cells
• When blood sugar decreases, liver
cells degrade glycogen, release
glucose
Lipids
• Most include fatty acids
– ____
– Phospholipids
• Steroids have no fatty acids
• Tend to be ________ in water
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Fats
• Fatty acid(s)
attached to
glycerol
• Triglycerides
are most
common
Phospholipids
• Main components of ____
____________
Sterols and Derivatives
• No fatty acids
• Rigid backbone of
four fused-together
carbon rings
• __________- most
common type in
animals
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Proteins
Amino Acid Structure
carboxyl
group
amino
group
R group
Protein Synthesis
• Protein is a chain of _____ ____ linked
by peptide bonds
• Peptide bond
– Type of covalent bond
– Links amino group of one amino acid with
carboxyl group of next
– Forms through __________ _______
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Primary Structure
• Sequence of amino acids
• Unique for each protein
• Influences shape of the protein
one
peptide
group
Secondary Structure
• Hydrogen bonds form between different
parts of polypeptide chain
• These bonds give rise to coiled or
extended pattern
• ________ or __________ ______
Examples of Secondary
Structure
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Tertiary Structure
heme group
Folding as a
result
of interactions
between R
groups
coiled and twisted polypeptide
chain of one globin molecule
Quaternary Structure
Some proteins
are made up of
more than one
polypeptide
chain
Hemoglobin
Denaturation
• Disruption of three-dimensional shape
• Breakage of weak bonds
• Causes of denaturation:
– __
– __________
• Destroying protein shape disrupts
__________
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Nucleotide Structure
• Sugar
– Ribose or ____________
• At least one phosphate group
• Base
– Nitrogen-containing
Nucleotide Functions
• ________ _______
• Coenzymes
• Chemical messengers
• Building blocks for
_______ _____
ATP - A Nucleotide
base
three phosphate groups
sugar
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Nucleic Acids
Adenine
Cytosine
• Composed of nucleotides
• Single- or double-stranded
• Sugar-phosphate backbone
____
• Double-stranded
• Consists of four
types of
nucleotides
• A bound to T
• C bound to G
RNA
• Usually single strands
• Four types of nucleotides
• Unlike DNA, contains the base _______ in
place of ______
• Three types are key players in ________
__________
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