1 the structure and function of macromolecules polymer principles and macromolecules polymer...
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THE STRUCTURE AND FUNCTION THE STRUCTURE AND FUNCTION OF MACROMOLECULESOF MACROMOLECULES
Polymer principles
And
Macromolecules
Polymer principles
And
Macromolecules
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• Cells join تربط smaller organic molecules (MonomersMonomers) together to form larger molecules (macromolecules) macromolecules) ((PolymersPolymers)), which may be composed of thousands of atoms.
• Macromolecules are organic molecules that weigh more than 100,000 daltons (ATOMIC MASS UNIT).
• The four major classes of macromolecules are:
1)1)-Carbohydrates, -Carbohydrates, 2)2)-Lipids, -Lipids, 3)3)-Proteins, -Proteins, 4)4)-Nucleic acids (-Nucleic acids (will be studied laterwill be studied later))
Polymers principlesPolymers principles
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• Monomers are connected by Monomers are connected by covalent covalent bondsbonds by by a a dehydration reaction dehydration reaction
الماء نزع الماء تفاعل نزع ..تفاعل– One monomer provides a One monomer provides a hydroxyl hydroxyl
groupgroup and and the other provides a the other provides a hydrogenhydrogen to form water.to form water.
– This process requires energy and is This process requires energy and is aided by aided by enzymes. enzymes.
• The covalent bonds connecting monomers in a polymer are disassembledThe covalent bonds connecting monomers in a polymer are disassembled
ــر ــرتُـكَس� الماء تفاعلتفاعل by by hydrolysis hydrolysis (hydration) reaction (hydration) reaction تُـكَس� الماء إضافة إضافة ..– In hydrolysis as the covalent bond is broken a In hydrolysis as the covalent bond is broken a
hydrogen atom and hydroxyl group from a split hydrogen atom and hydroxyl group from a split water molecule attaches where the covalent water molecule attaches where the covalent bond used to be.bond used to be.
– Hydrolysis reactions dominate the digestive Hydrolysis reactions dominate the digestive process, guided by specific enzymes. process, guided by specific enzymes.
(Carbohydrates, Lipids, Proteins and nucleic (Carbohydrates, Lipids, Proteins and nucleic acids)acids)
Mono-mer Di-mer Poly-mer
PolymerPolymer is a long molecule consists of a chain of is a long molecule consists of a chain of similar building molecules (similar building molecules (monomersmonomers) covalently ) covalently bonded together.bonded together.
أحادأحاديي
ثنائثنائيي
عديدعديد
A. CarbohydratesA. Carbohydrates
1. Monosaccharides: are the simplest carbohydrates (simple sugars).are the simplest carbohydrates (simple sugars).
contain a single sugar moleculecontain a single sugar molecule
2. Disaccharides: contain two monosaccharides joined via dehydration contain two monosaccharides joined via dehydration
synthesissynthesis
3. Polysaccharides: are polymers of many monosaccharides.are polymers of many monosaccharides.
Sugars, Carbo = carbon, hydrate = water; Used as an immediate energy sourceCarbon to hydrogen to oxygen ratio = 1:2:1
AldosAldosee
AldosAldosee
Asymmetric Asymmetric CC
Asymmetric Asymmetric CC
1- Monosaccharides 1- Monosaccharides الَسكرالَسكر األحادياألحادي
C
C
C
C
C
C
OOHH
OOHH
HH
OOHH
HH
OOHH
HH
OOHH
HH
OOHH
HH
HH
CC
C
C
C
C
C
OOHH
OOHH
OOHH
OOHH
OOHH
HH
HH
HH
HH
OOHH
HH
HH
GlucosGlucoseeCC66HH1212OO66
GalactoseGalactoseCC66HH1212OO66
Aldehyde sugars
• An OH group is attached to each carbon except one, which is double bonded to an oxygen (carbonyl).
KetosKetosee
C
C
C
C
C
C
OOHH
HH
OOHH
OOHH
OOHH
OOHH
HH
HH
HH
HH
OO
HH
HH
FructosFructoseeCC66HH1212OO66
C
C
C
OOHH
OOHH
HH
OOHH
HH
HH
Glyceraldehyde
C
C
C
C
C
OOHH
OOHH
OOHH
OOHH
HH
HH
HH
OOHH
HH
HH Ribose
Ketone sugar
Triose Triose SugarSugar
Pentose SugarPentose Sugar Hexose Hexose SugarSugar
Monosaccharides are classified as followingMonosaccharides are classified as following
Aldoses: are the monosaccharides with the carbonyl group
(C=O) at the end of CC chain (e.g. Glucose).
Ketoses: are the monosaccharides with the C=O carbonyl group within داخل the CC chain (e.g. Fructose).
Triose (3C3C): e.g. Glyceraldehyde.
A- Based on the location of the A- Based on the location of the
carbonyl groupcarbonyl groupC=OC=O
B- Based on the number of B- Based on the number of CC in the skeleton in the skeleton
Pentose (5C5C): e.g. Ribose.
HexoseHexose (6C6C): e.g. Glucose, Fructose and Galactose.
2- Disaccharides 2- Disaccharides السكر السكرييالثنائالثنائ
Consist of 2 monosaccharide molecules joined during Consist of 2 monosaccharide molecules joined during a a dehydrationdehydration reaction reaction الماء نزع الماء تفاعل نزع ..تفاعل
SucroseSucrose ( (table sugartable sugar): consists of ): consists of Glucose + Glucose + FructoseFructose..
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3- Polysaccharides 3- Polysaccharides السكر السكرالعديدالعديد
Consists of few Consists of few hundredshundreds to few to few thousandsthousands of monosaccharides. of monosaccharides.
They are two types:They are two types:
1- Storage1- Storage تخزينيةتخزينية. . Provide sugarProvide sugar for cell by hydrolysis for cell by hydrolysis إضافة إضافة . .ماءماء
2- Structural 2- Structural تركيبية. . Serve as Serve as building materialsbuilding materials for the for the organism. organism.
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I- Starch (in plants) النشا
A storage polysaccharide of plants (A storage polysaccharide of plants (within plastids).).
It consists of thousands of It consists of thousands of glucose glucose molecules. molecules.
Thus, it gives glucose when Thus, it gives glucose when hydrolysed hydrolysed الماء by special enzymes in by special enzymes in بإضافةhumanshumans . . PotatoesPotatoes and and grainsgrains are the major source of starch. are the major source of starch.
A)- Storage A)- Storage تخزينيةتخزينية PolysaccharidesPolysaccharides
II- Glycogen II- Glycogen (in animals)
الجليكوچـينالجليكوچـينStored in animal cells (Stored in animal cells (e.g. liver and muscle cells in Human).).
It is consists of thousands of It is consists of thousands of glucose moleculesglucose molecules..
Thus, it gives glucose when hydrolysed. Thus, it gives glucose when hydrolysed.
B)- Structural B)- Structural تركيبيةتركيبية PolysaccharidesPolysaccharides
I- CelluloseI- Cellulose
Forms the micro-fibrils and cell wall in plants.Forms the micro-fibrils and cell wall in plants.
It is consists of thousands of It is consists of thousands of ββ glucoseglucose molecules. molecules.
Humans cannot digest it, but some bacteria and protozoa can (Humans cannot digest it, but some bacteria and protozoa can (e.g. in Termites and Cows stomach). ).
It is the building material of plants (cell wall).It is the building material of plants (cell wall).
II- Chitin II- Chitin الكيتينالكيتين
It is consists of thousands of glucose molecules with a NN atom in one end.
It is used to manufacture the surgical threads.
It is the building material of the cuticle يد� ـَل Kالُج in insects.
CarbohydratesCarbohydrates
AldoseAldoseC=O on top
KetoseKetoseC=O in chain
(Glucose)(Glucose)
MonosaccharidMonosaccharideses
DisaccharideDisaccharidess
PolysaccharidePolysaccharidess(Sucrose)(Sucrose)
StorageStorage StructuraStructurallStarch (Starch (inin plantsplants) )
& &
Glycogen (Glycogen (inin animalsanimals))
Cellulose (Cellulose (inin plantsplants))
& & Chitin ( Chitin (inin insectsinsects))
No. of sugar moleculesNo. of sugar molecules
Location of Location of Carbonyl Carbonyl
GroupGroup
No. of No. of CC atoms atoms
TrioseTriose ( (3C3C) ) GlyceraldehydeGlyceraldehyde
Pentose (Pentose (5C5C) ) RiboseRibose
Hexose (Hexose (6C6C))GlucoseGlucose