Download Organic Compounds: Carbohydrates

Organic Compounds: Carbohydrates
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Carbohydrates – include sugars and starches
Contain the elements C,H,O (H & O ratio like water, 2
H’s to 1O), ex. glucose C6H12O6
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Word means “hydrated carbon”
Classified according to size: monosaccharides,
disaccharides, or polysaccharides
Monosaccharides (common name = simple sugars)
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Means “one sugar”, single chain or single-ring structures
containing 3 to 7 carbon atoms
Important to body: glucose, fructose, galactose, ribose,
deoxyribose
Pentose - 5C monosaccharide
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Ribose, Deoxyribose – nucleic acids and DNA
Hexose - 6C monosaccaride
glucose – universal cell fuel, blood sugar
 fructose – converted to glucose
 galactose – converted to glucose
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Organic Compounds: Carbohydrates
 Disaccharides
– double sugars, formed when two
simple sugars are joined by a simple synthesis
reaction, called dehydration synthesis
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sucrose = glucose + fructose “cane sugar”(requires
protein enzyme, sucrase, to decompose to simple
sugars)
maltose = glucose + glucose “malt sugar”(requires
protein enzyme, maltase, to decompose to simple
sugars)
lactose = “in milk” glucose + galactose (requires
protein enzyme, lactase, to decompose to simple
sugars)
All double sugars are too large to pass through cell
membrane, must be broken down to be absorbed
by process hydrolysis – water added to bond, bond
breaks, then simple sugar is released
Organic Compounds: Carbohydrates
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Polysaccharides “many sugars” – are long, branching
chains of linked simple sugars
Because they are large, insoluble molecules, ideal for
storage, also lack sweetness of simple & double sugars
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Glycogen- storage polysaccharide found in animal tissues
(liver & muscles)
Starch – storage polysaccharide formed by plants (potatoes
& carrots)
Cellulose (made of a different isomer of glucose, betaringed glucose, and cannot be digested by humans)
Carbohydrate Functions:
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ready, easily used source of energy for cells to make ATP
part of structure of DNA and RNA (pentose sugars - ribose
and deoxyribose)
recognition sites on cell membrane surfaces
Organic Compounds: Lipids
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Lipids – organic molecules that contain: C, H, O
Carbon & Hydrogen far outnumber the Oxygen atoms
ex. C57H110O6 - tristearin
Most are insoluble in water, but will dissolve in other lipids
and in other solvent such as acetone and alcohol
Presence of P & N in some of the lipids
Triglycerides (Neutral Fats) – composed of two types of
building blocks: fatty acids & glycerol
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Synthesis involves attachment of 3 fatty acids to a single
glycerol molecule-results in an E shaped molecule that
resembles the tines of a fork
Maybe solid-typical of animal fats or liquid- plant oils
Animal oils tend to be saturated, plant oils are unsaturated
saturated fats- all carbons single bonds
 unsaturated fats- carbons have some double and triple bonds
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Most abundant & concentrated source of energy-when
oxidized yield large amounts of energy
Stored chiefly in fat deposits beneath skin & around organs,
where help insulate body and protect deep tissues
Triglycerides
Organic Compounds: Lipids
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Phospholipids- similar to neutral, but differ in that a
phosphorus group is attached & takes place of one
of fatty acid chains
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Phosphorus portion “the head” contains an electrical
charge gives special chemical properties and polarity
Consists of a polar head attracts & interacts with water
& ions but the nonpolar tail does not interact
Found in cell membranes and allows cells to be
selective about what may enter or leave
Steroids –flat molecules formed of 4 interlocking rings,
look different than other 2 lipids, but act similar (C,H
and lipid soluble)
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Examples - cholesterol, vitamin D, hormones, bile salts
Cholesterol from food & in cell membranes, abundant in
brain, provides raw material to produce vitamin D, some
hormones, & bile salts
Phospholipids
Steroids
Organic Compounds: Proteins
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Proteins- a nitrogenous substance made up of amino acids
Contains C,H,O,N & sometimes S
Account for over 50% of the organic material in the body,
and most varied in their functions of all the organic
molecules
amino acids – are the building blocks of proteins, about 20
types
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Have 3 components:
-COOH (carboxyl) group – allow them to act as acids
-NH2 (amine) group – gives basic properties
R-group – what is different for each that makes them
chemically unique
Amino acids joined in chains to form complex protein
molecules that contain from 50 to thousands of amino acids
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Polypeptide – fewer than 50 amino acids
Each amino acid is distinct, sequence in which they are
bound produce proteins that vary widely in both structure
and function
Classifying Proteins
 Fibrous
Proteins- are strand like, are also called
“structural proteins”
 Appear most often in body structures, important
in binding structures together and in providing
strength to certain body tissues, very stable
 Ex. - Collagen – found in bones, cartilage, and
tendons-most abundant protein in body
 ex. Keratin – found in hair, nails, and makes the
skin tough
Classifying Proteins
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Globular Proteins – mobile, spherical molecules that
play critical roles in many biological processes, they do
things rather than just form structures, are also called
“functional proteins”, not stable
 Some are antibodies (provide immunity), hormones
(regulate growth & development), enzymes (catalysts
for chemical reactions)
 Hydrogen bonds are critically important in
maintaining structure, but are fragile & easily broken
by heat and pH changes
 When the 3 dimensional structure is destroyed, called
denatured proteins, no longer can perform their roles
(function depends on structure)
 active sites – are structure on their surface that “fit” or
interact with other molecules, ex. hemoglobin- has
pepsin, that is inactivate by blood pH becoming to
alkaline
Classifying Proteins
 Enzymes-
are functional proteins that act as
biological catalysts
 Catalyst- substance that increases the rate
of a chemical reaction without be
consumed or changed itself
 change
reaction
 Enzymes
the energy of activation for a chemical
usually end in –ase
 Enzymes are often produced in a inactive
form and must be activated before can
function, in some a cases are inactivated
immediately after function(blood clotting)
Proteins
Support
structural proteins (e.g., keratin, collagen)
Enzymes
speed up chemical reactions
Transport
cell membranes channels, transporters in blood
(e.g., Hemoglobin)
Defense
antibodies of the immune system
Hormones
cell signaling (e.g., insulin)
Motion
contractile proteins (e.g., actin, myosin)
Organic Compounds: Nucleic Acids
 Nucleic
acids – make up genes, composed of
carbon, oxygen, hydrogen, nitrogen, and
phosphorous atoms
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Largest biological molecules in the body
Their building blocks, the nucleotide, are very
complex
3 components: 1)nitrogen containing base, 2)
pentose (5 carbon sugar), & 3) phosphate group
5 types of Nitrogen bases: 1)adenine(A), 2) guanine
(G), 3) cytosine (C), 4) thymine(T), & 5) uracil (U)
Two major kinds of nucleic acid: 1. deoxyribonucleic
acid (DNA) & 2. ribonucleic acid (RNA)
Nucleotide Structure
Nucleic Acids: DNA
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the genetic material found in the nucleus
Replicate itself exactly before cell divides
Provides instructions for building every cell in the
body
Long double chain of nucleotides
Bases are A,G,T,C
Sugar deoxyribose
Double stranded helix shape-chains held together
by hydrogen bonds between bases (spiral
staircase)
Complementary base pairs – A binds with T, and G
binds with C
DNA
Nucleic Acids: RNA
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Located outside nucleus and can be considered the
“molecular slave” of DNA
Caries out the orders from the DNA for protein synthesis
Consists of single nucleotide strands
Bases A,G, C, and U instead of T
Sugar is ribose
3 types of RNA: 1) messenger RNA, 2) ribosomal RNA, & 3)
transfer RNA, each w/specific role in carrying out DNA’s
instructions
Messenger RNA – carries info. For building protein from DNA
genes to ribosomes
 Transfer RNA – ferries/caries amino acids to the ribosomes
 Ribosomal RNA – forms part of the ribosomes, where it
oversees the “translation” of the message & the binding
together of amino acids to from proteins
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ATP
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Adenosine Triphosphate (ATP) – provides a form of chemical
energy that is useable by all body cells
w/out ATP, molecules cannot be made or broken down, cells
cannot maintain their boundaries, all life processed would
stop
Glucose is most important “fuel”, but none of its chemical
energy contained in its bonds can be used directly
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Energy released as glucose instead is catabolized (captured)
and stored in the bond of ATP molecules as small “packets” of
energy
Structurally it is a modified nucleotide, consists of an adenine
base, ribose sugar, & 3 phosphate groups
When the high energy phosphate bonds are broken by
hydrolysis, energy that can be used immediately by the cell is
liberated
ATP be compared to a tightly coiled spring that is ready to
uncoil w/tremendous energy when the “catch” is released
How ATP Drives Cellular Work
THE BIG PICTURE
Chemistry is essential for life…