Requirements of carbohydrates in animals and human body!

1. CarbohydratesCarbohydrates

2. CarbohydratesCarbohydrates
 Majo r so urce o f energy.Majo r so urce o f energy.
 Organic co mpo unds made up o fOrganic co mpo unds made up o f
CarbonCarbon,, HydrogenHydrogen andand OxygenOxygen..
 Ratio o f hydro gen and o xygen is 2: 1 ,Ratio o f hydro gen and o xygen is 2: 1 ,
as in water.as in water.
 Generalfo rmula:Generalfo rmula: Cx(H2O)y

3.  Chemically carbo hydrates are definedChemically carbo hydrates are defined
asas polyhydroxyaldehydespolyhydroxyaldehydes o ro r ketonesketones..
 PhotosynthesisPhotosynthesis in green plants is thein green plants is the
majo r so urce o f carbo hydrates.majo r so urce o f carbo hydrates.
CO2 + H2OCO2 + H2O  carbohydrates + O2carbohydrates + O2
 Play bo thPlay bo th structuralstructural andand functionalfunctional
ro le in living o rganisms.ro le in living o rganisms.

4. ClassifiCation ofClassifiCation of
CarbohydratesCarbohydrates
Carbo hydrates are classified into threeCarbo hydrates are classified into three
main gro ups acco rding to theirmain gro ups acco rding to their
mo lecular structure, namely:mo lecular structure, namely:
1 . Mo no saccharides1 . Mo no saccharides
2. Disaccharides2. Disaccharides
3. Po lysaccharides3. Po lysaccharides

5. MonosaCCharidesMonosaCCharides
 Simple sugars that disso lve in waterSimple sugars that disso lve in water
to fo rm sweet so lutio ns.to fo rm sweet so lutio ns.
 Generalfo rmula:Generalfo rmula: (CH2O)n(CH2O)n
 Canno t beCanno t be hydrolyzedhydrolyzedintointo simplersimpler
sugars.sugars.
 Names o f sugars usually end inNames o f sugars usually end in –ose–ose..

6.  Allcarbo n ato ms except o ne, have anAllcarbo n ato ms except o ne, have an
–OH–OH gro up.gro up.
 Sugar with aldehyde gro up is calledSugar with aldehyde gro up is called
aldo-sugaraldo-sugar whereas sugar with ketowhereas sugar with keto
gro up is agro up is a keto-sugarketo-sugar..

7.  Mo no saccharides co ntainMo no saccharides co ntain 33toto 77
carbo n ato ms.carbo n ato ms.
 Classificatio n acco rding to theClassificatio n acco rding to the
number o f carbo n ato ms in eachnumber o f carbo n ato ms in each
mo lecule, ismo lecule, is;; triosestrioses (3C),(3C), pentosespentoses
(5C), and(5C), and hexoseshexoses (6C).(6C).

8. IsomersIsomers
Two fo rms o f the same chemical.Two fo rms o f the same chemical.
Pento ses and hexo ses fo rm ring structurePento ses and hexo ses fo rm ring structure
in so lutio n.in so lutio n.
 the form with – OH
belo w the ring is alpha-
glucose.
The form with – OH
belo w the ring is beta-
glucose.

9.  Allmo no saccharides are reducing sugars.Allmo no saccharides are reducing sugars.
 Co mmo n mo no saccharides areCo mmo n mo no saccharides are glucoseglucose,,
fructosefructose andand galactosegalactose..

10. OH
OH
H
H
HO
CH2OH
H
H
H
OH
O
source and usessource and uses
 Gluco se serves as the essentialGluco se serves as the essential
energy so urce, and is co mmo nly kno wn asenergy so urce, and is co mmo nly kno wn as
blo o d sugar o r dextro se.blo o d sugar o r dextro se.
 Fructo se is the sweetest, o ccurs naturallyFructo se is the sweetest, o ccurs naturally
in ho ney and fruits, and is added to manyin ho ney and fruits, and is added to many
fo o ds in the fo rm o f high-fructo se co rnfo o ds in the fo rm o f high-fructo se co rn
syrup.syrup.
 Galactoserarely occursnaturally asaGalactoserarely occursnaturally asa
singlesugar.singlesugar.

11. dIsaccharIdesdIsaccharIdes
 Two mo no saccharides jo in to gether by theTwo mo no saccharides jo in to gether by the
pro cess o fpro cess o f condensationcondensation to make ato make a
disaccharide.disaccharide.
 Co mparatively less so luble and less sweetCo mparatively less so luble and less sweet
in taste.in taste.
 Co valent bo nd between twoCo valent bo nd between two
mo no saccharides is kno wn as themo no saccharides is kno wn as the
glycosidic bondglycosidic bond..

12. synthesIssynthesIs
mono = one
saccharide = sugar
di = two
2 sugars =
disaccharide
1 sugar =
monosaccharide
|
glucose
|
glucose
|
maltose

13. 1 sugar =
monosaccharide
2 sugars =
disaccharide
|
glucose
|
fructose
|
sucrose
(table sugar)
How sweet
it is!

14. 1 sugar =
monosaccharide
2 sugars =
disaccharide
Milk
Sugar!

15. PolysaccharidesPolysaccharides
 Po lymers who se subunits arePo lymers who se subunits are
mo no saccharides linked to gether bymo no saccharides linked to gether by
glyco sidic bo nds.glyco sidic bo nds.
 Mo st co mplex and mo st abundantMo st co mplex and mo st abundant
carbo hydrates in nature.carbo hydrates in nature.
 Usually branched and tasteless.Usually branched and tasteless.
 High mo lecular weights.High mo lecular weights.
 Sparingly so luble in water.Sparingly so luble in water.
poly = many

16. starchstarch
glucose + glucose + glucose… = polysaccharide
starch
(plant)
glycogen
(animal)
energy
storage

18. starch and glycogenstarch and glycogen
 Main so urce o fMain so urce o f
carbo hydrate fo rcarbo hydrate fo r
animals.animals.
 Energy sto rage inEnergy sto rage in
plants.plants.
 Fo und in fruitsFo und in fruits
grains, seeds andgrains, seeds and
tubers.tubers.
 Blue co lo r withBlue co lo r with
io dine.io dine.
 Energy sto rage inEnergy sto rage in
animals.animals.
 Fo und abundantly inFo und abundantly in
liver and muscles.liver and muscles.
 Inso luble in water.Inso luble in water.
 Red co lo r with io dine.Red co lo r with io dine.
 Symbo lized by theSymbo lized by the
fo rmula:fo rmula:
(C6H1 0O5)n(C6H1 0O5)n

19. CelluloseCellulose
Cellwalls in plantsCellwalls in plants
• herbivo res can digest cellulo se wellherbivo res can digest cellulo se well
• mo stmo st carnivo res canno t digest cellulo secarnivo res canno t digest cellulo se
that’ s why theythat’ s why they
eat meateat meat
to get their energyto get their energy
& nutrients& nutrients
cellulo se = ro ughagecellulo se = ro ughage
• stays undigestedstays undigested
• keeps materialkeeps material
mo ving in yo urmo ving in yo ur
intestinesintestines

20. ChitinChitin
 Amajo r co mpo nent o fAmajo r co mpo nent o f
exo skeleto n o fexo skeleto n o f
arthro po ds e.g. lo bstersarthro po ds e.g. lo bsters
and crabs.and crabs.