1. CLASSIFICATION OF CARBOHYDRATES
MONOSACCHARIDE
ALDOSE
KETOSE
DISACCHARIDE
POLYSACCHARIDE
MALTOSE
LACTOSE
SUCROSE
STARCH
GLYCOGEN
CELLULOSE
GLUCOSE
GALACTOSE
FRUCTOSE

2. STARCH, GLYCOGEN & CELLULOSE
Polysaccharides are ubiquitous in nature.
They are called Homopolysaccharides, when made from same sugars and Heteropolysaccharides when made from different sugars.
They can be linear or branched. Linear chains are made of α-1→4 bonds and branch is made of α-1→6 bonds

3. STARCH Is a storage polysaccharide in Plants MADE OF α – GLUCOSE.
AMYLOSE – Linear, linked by α 1→ 4 bonds. [15 – 20%].
AMYLOPECTIN – Branched, linked by α 1→ 6 bonds. [80 – 85%]
Branch point after every 30 Glc unit.

4. GLYCOGEN
Storage polysacc in animals, highly branched. Similar to Amylopectin
Branch point every 8 – 12 Glc units
Has only 1 reducing end but many non-reducing ends

5. CELLULOSE Similar to Amylose, linear but made of β 1→ 4 bonds.
Very long chains – 15,000 – 20,000 Glc units
Can’t be digested because amylase recognises only ‘α’ bonds
Microorganism in gut Trichonympha secretes cellulase, which breaks down cellulose to short chain FA, a energy source

6. METABOLISM
Co-ordinated and specific reactions – organised as PATHWAYS…
PRIMARY FUNCTIONS:
Acquiring and Utilising Energy
Synthesis of structural components of cell eg Membrane
Growth & Development
Removal of waste products
GENERAL CHARACTERISTIC – of BIOCHEMICAL REACTIONS:
No. of reaction types are few – eg., Hydrolysis, Oxidation-reduction etc.
One enzyme usually catalyses only One reaction
Only a few important pathways inside cell – Glycolysis, Gluconeogenesis,
TCA cycle, Urea cycle, β-Oxidation etc.
Anabolic and Catabolic Pathways

7. CARBOHYDRATES METABOLISM GLYCOLYSIS Glycolysis is a Amphibolic pathway
It occurs in Eukaryotes & Prokaryotes
It occurs in cytoplasm of cell
Total 10 reactions in 2 phases
End product depends on presence of O2

8. Preparatory
Pay Off

9. ENERGETICS:
2 ATP
2 NADH = 6ATP
FATE OF PYRUVATE

10. GLUCONEOGENESIS
Pyruvate Carboxylase & PEP Carboxykinase function inside mitochondria

11. CORI CYCLE

12. HMP Shunt AIM: To produce NADPH, involved in biosynthetic reactions
To produce Ribose-5-P, a precursor for DNA synthesis

13. HMP Shunt

14. Phase I
SUMMARY
1) Phase – I
NADPH & Rib-5-P produced
2) Phase – II
Transketolase & Transaldolase
involved
Phase II

15. TCA CYCLE Final pathway for oxidation of CHO, PTN & Lipid
Occurs in Mitochondrial Matrix
End product is Acetyl CoA
Series of dehydrogenation & decarboxylation rxns
Each cycle generates 12 ATP’s
It is amphibolic in nature
FORMATION OF ACETYL COA:
ENERGETICS:
2 NADH = 6 ATP

16. TCA CYCLE ENERGETICS: 3 NADH = 9ATP 1 FADH2 = 2 ATP 1 GTP = 1 ATP
TOTAL = 12 ATP
ACONITASE
CITRATE SYNTHASE
ISOCITRATE dehydrogenase
MALATE dhase
GLUCOSE OXIDATION:
GLYCOLYSIS = 8 ATP
ACETYL CO-A = 6 ATP
TCA CYCLE = 24 ATP
TOTAL = 38 ATP
KETO GLUTARATE dehydrogenase
FUMARASE
SUCCINATE dhase
SUCCINATE THIOKINASE

17. AMPHIBOLIC NATURE

18. GLYOXYLATE CYCLE MAIN FEATURES: A modified form of TCA cycle
Occurs in Plants – during Germination stage
Helps to form Glucose from Lipid stores
Key enzymes – Isocitrate Lyase & Malate synthase
present inside Glyoxysomes.
Involves participation of 3 compartments inside cell;
glyoxysomes, mitochondria & cytosol

19. GLYCOGENOLYSIS Occurs from non-reducing end.
Takes place in muscle & liver
Glucose units enter glycolysis by the help of 3 enz:-
Glycogen phosphorylase
Glycogen debranching enzyme
Phosphogluco mutase
GLYCOGEN
GLUCOSE – 1 – P
GLUCOSE – 6 – P

20. GLYCOGENOLYSIS Glycogen debranching enz reaction
Acts at a branch point when it’s 4 glc long.
Transfers a 3 glc unit from branch point to a
longer chain for p’lase action to continue
Last glc residue at branch removed as well
Phosphogluco mutase reaction
Glc-1-P → Glc-6-P

21. GLYCOGENESIS Starts when UDP-Glc & Glycogenin are available.
4 enz involved:-
a) Phosphogluco mutase
Glc-6-P → Glc-1-P
b) UDP-glucose pyrophosphorylase
Glc-1-P + UTP → UDP-glc + PPi
c) Glycogen synthase – Transfers glc to non-
reducing end. Acts until branch is 11 unit
long
d) Glycogen branching enzyme – Transfers 6
or 7 glc from a branch containing 11 glc units to
a more interior position creating a new
branch.

22. GLYCOGENESIS
c) Glycogen synthase – Transfers glc to non-reducing end. Acts until branch is 11 unit long

23. GLYCOGENESIS
d) Glycogen branching enzyme – Transfers 6 or 7 glc from a branch with 11 glc units to a more interior position creating a new branch.