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State Board · Class 11 · Biology

Lesson 6: Biomolecules

7 concepts · 56 practice questions with answers · Free to read

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Introduction to biomolecules, monosaccharides and disaccharides

Link to Std 9–10

A chemical deepening of the food components (carbohydrates, fats, proteins) and DNA of Std 9–10.

From daily life

Sugar dissolves in tea and milk contains lactose; both are carbohydrates but differ in molecular makeup (sucrose vs lactose).

Simple definition

Biomolecules = chemical molecules of living beings. Macromolecules: polysaccharides, proteins, nucleic acids (polymers); micromolecules: lipids etc. Carbohydrates Cx(H₂O)y: monosaccharide (CH₂O)n, disaccharide, polysaccharide.

Biomolecules and disaccharidesBiomoleculesMacromolecules (polymers)MicromoleculesCarbohydrate → monosaccharideProtein → amino acidNucleic acid → nucleotideLipids, secondary metabolites(inorganic: prime, macro, trace elements)Carbohydrate: Cx(H₂O)y ; H : O = 2 : 1Disaccharidemade of (condensation)typeSucroseGlucose + Fructosenon-reducingLactoseGlucose + GalactosereducingMaltoseGlucose + GlucosereducingGlycosidic bond joins sugars; all monosaccharides are reducing

In the figure : Classification of biomolecules and three disaccharides.

Rule 1 : Monosaccharides — (CH₂O)n, n = 3–7: triose, tetrose, pentose (ribose/deoxyribose), hexose (glucose, fructose, galactose). Aldose (–CHO: glucose) and ketose (C=O: fructose). All are reducing sugars (Benedict's reagent). Blood glucose ≈ 90 mg/100 mL.

  • Easy : Glucose = blood sugar; fructose = fruit sugar; galactose = part of lactose.
  • Medium : Ribose in RNA, deoxyribose in DNA.
  • Exam-type (CET) : Benedict's test: Cu²⁺ → Cu⁺ (reducing sugar).

Rule 2 : Disaccharides — Two monosaccharides join by condensation (water released, energy required) with a glycosidic bond. Sucrose = glucose + fructose (non-reducing); lactose = glucose + galactose; maltose = 2 glucose (both reducing). Hydrolysed to monosaccharides in the intestine.

  • Easy : C₁₂H₂₂O₁₁ + H₂O → 2 C₆H₁₂O₆ (hydrolysis).
  • Medium : Sucrose = cane sugar; lactose = milk sugar; maltose = malt sugar.
  • Exam-type (CET) : A disaccharide cannot cross the membrane, so it must be broken down.
Remember

Sucrose = G+F (non-reducing); lactose = G+Ga; maltose = G+G.

Common mistake and CET trap

‘Sucrose is reducing’ is wrong. Trap: ‘fructose is an aldose’ is wrong (ketose).

Shortcut

Memory clue : "SuFG, LGGa, MGG: Sucrose (F+G), Lactose (G+Ga), Maltose (G+G)".

Spot the difference

SugarMade ofReducing?
SucroseG + FNo
LactoseG + GaYes
MaltoseG + GYes

Practice questions

Easy
  1. 1General formula of carbohydrates?
  2. 2Give an example of monosaccharide.
  3. 3What is a glycosidic bond?
Medium
  1. 4What makes sucrose?
  2. 5Where is lactose found?
  3. 6What is a reducing sugar?
Challenging
  1. 7Aldose vs ketose.
  2. 8Condensation vs hydrolysis.
Show answers (try them yourself first)
  1. 1Cx(H₂O)y.
  2. 2Glucose / fructose / galactose.
  3. 3Bond joining two sugar units.
  4. 4Glucose + fructose.
  5. 5In milk.
  6. 6Sugar with free aldehyde/ketone that reduces Benedict's reagent.
  7. 7Aldose has –CHO; ketose has C=O.
  8. 8Joining with loss of water / breaking with addition of water.

Polysaccharides

From daily life

Rice, bread and a cotton thread are all long chains of glucose; only the chain structure differs.

Simple definition

Polysaccharides = polymers of many monosaccharides. Homopolysaccharides (one sugar: starch, glycogen, cellulose) and heteropolysaccharides (hyaluronic acid, heparin, chondroitin sulphate).

Starch, glycogen and celluloseAmyloseunbranched helixAmylopectinbranched; insolubleGlycogenhighly branched; liver & muscleCelluloseβ-glucose; straight chains + H-bondsStarch = plant reserve | glycogen = animal reserve | cellulose = cell wallHomo = one kind of sugar | hetero = different (hyaluronic acid, heparin)Chitin (insect exoskeleton) = polysaccharide

In the figure : Structures of amylose, amylopectin, glycogen and cellulose.

Rule 1 : Starch and glycogen — Starch = plant reserve food; α-glucose; amylose (unbranched, helical, colloidal in hot water) and amylopectin (branched, insoluble). Glycogen = amylopectin with very short branch spacing; animal reserve, in liver and muscle.

  • Easy : Starch + iodine = blue colour (simple test).
  • Medium : Glycogen = ‘animal starch’.
  • Exam-type (CET) : When needed, glycogen → glucose (hydrolysis).

Rule 2 : Cellulose and others — Cellulose = straight chain of β-glucose; hydrogen bonds between chains make it strong; plant cell wall. Chitin = polysaccharide of insect exoskeleton. Heteropolysaccharides: hyaluronic acid, heparin, blood-group substances.

  • Easy : Cotton ≈ pure cellulose.
  • Medium : Polysaccharide properties depend on length, branching and folding.
  • Exam-type (CET) : Polysaccharides are too big to leave the cell.
Remember

Starch (α, plants), glycogen (animals), cellulose (β, cell wall).

Common mistake and CET trap

‘Cellulose is of α-glucose’ is wrong (β). Trap: ‘amylose is branched’ is wrong.

Shortcut

Memory clue : "Starch = Store, Cellulose = Cell wall, Glycogen = Go (liver/muscle)".

Spot the difference

SubstanceUnitRole
Starchα-glucosePlant store
Glycogenα-glucoseAnimal store
Celluloseβ-glucoseCell wall

Practice questions

Easy
  1. 1Two forms of starch.
  2. 2Where is glycogen stored?
  3. 3What is cellulose made of?
Medium
  1. 4One example each of homo and hetero.
  2. 5Where is chitin found?
  3. 6Why is cellulose strong?
Challenging
  1. 7Amylose vs amylopectin.
  2. 8Biological significance of polysaccharides.
Show answers (try them yourself first)
  1. 1Amylose, amylopectin.
  2. 2Liver and muscle.
  3. 3β-glucose.
  4. 4Starch; hyaluronic acid.
  5. 5In the insect exoskeleton.
  6. 6Straight chains with hydrogen bonds between them.
  7. 7Unbranched helical / branched, insoluble.
  8. 8Reserve food; wall/membrane structure; energy.

Lipids

From daily life

Ghee, oil and wax do not mix with water; this is the common trait of lipids.

Simple definition

Lipids = fatty acids and their derivatives; insoluble in water, soluble in organic solvents; H : O > 2 : 1. Classes: simple (fats, waxes), compound (phospholipids, glycolipids) and derived (sterols, cholesterol).

Fatty acids, triglyceride and phospholipidCOOHSaturated (no double bond)COOHUnsaturated (≥1 double bond)glycerol3 fatty acids = triglyceride (fat)ester bondPhospholipid: polar head + 2 tails(membrane bilayer)Wax: long fatty acid + long alcoholSteroid/cholesterol: four rings; phytosterols in plantsEssential fatty acids: linoleic, linolenic (from diet)

In the figure : Saturated/unsaturated fatty acid, triglyceride and phospholipid.

Rule 1 : Fatty acids and fats — Fatty acid = hydrocarbon chain + –COOH. Saturated: no double bond (palmitic, stearic). Unsaturated: ≥1 double bond (oleic, linoleic). Triglyceride = glycerol + 3 fatty acids (ester bonds). Unsaturated = liquid at room temperature (oil); hydrogenation → vanaspati. Uses: reserve food, insulation, cushioning.

  • Easy : Butter/ghee = mostly saturated; oil = unsaturated.
  • Medium : Subcutaneous fat retains heat.
  • Exam-type (CET) : Linoleic, linolenic = essential fatty acids.

Rule 2 : Wax, compound lipids and sterols — Wax = long fatty acid + long alcohol; waterproof coating (hair, leaves, beehive). Phospholipid = glycerol + 2 fatty acids + phosphate (+ N-group); polar head + non-polar tails → membrane bilayer. Glycolipid = with sugar (brain, myelin). Cholesterol = steroid; source of adrenal and sex hormones and vitamin D; plants have phytosterols; Dioscorea → diosgenin.

  • Easy : Phospholipids are amphipathic.
  • Medium : Cholesterol is in animals only, not in plants.
  • Exam-type (CET) : Diosgenin = raw material for birth-control pills.
Remember

Saturated = no double bond (solid); unsaturated = ≥1 (liquid); phospholipid = membrane.

Common mistake and CET trap

‘Cholesterol in plants’ is wrong. Trap: ‘oils are saturated’ is wrong.

Shortcut

Memory clue : "Sat = Solid; Unsat = liquid (double bond)".

Spot the difference

ClassExampleRole
SimpleFat, waxStore, coating
CompoundPhospholipidMembrane
DerivedCholesterolHormones

Practice questions

Easy
  1. 1What is a fatty acid?
  2. 2Saturated vs unsaturated.
  3. 3What forms a triglyceride?
Medium
  1. 4Function of phospholipid.
  2. 5Two uses of wax.
  3. 6Which substances come from cholesterol?
Challenging
  1. 7Where are glycolipids found?
  2. 8How is vanaspati made?
Show answers (try them yourself first)
  1. 1Hydrocarbon chain + –COOH.
  2. 2No double bond / has double bond.
  3. 31 glycerol + 3 fatty acids.
  4. 4Forms the bilayer of cell membrane.
  5. 5Waterproof coating; beehive.
  6. 6Adrenal/sex hormones, vitamin D.
  7. 7Brain, myelin sheath.
  8. 8Hydrogenation of unsaturated oil.

Proteins

From daily life

Proteins of dal, eggs and milk build muscle; hair and nails (keratin) too. All come from different combinations of 20 amino acids.

Simple definition

Proteins = polymers of amino acids joined by peptide bonds (–COOH + –NH₂); 20 kinds of amino acids. Berzelius (1830) coined ‘protein’ (proteios = first). Amphoteric; zero net charge at the isoelectric point.

Four levels of protein structure1) Primary: amino-acid sequence (peptide bond)α-helixpleated sheet (H-bonds)2) Secondary: helix / pleated sheet by H-bonds3) Tertiary: 3-D folding (S–S bonds etc.)4) Quaternary: several subunits (Hb)Simple, conjugated,derived

In the figure : Four structural levels of a protein: primary, secondary, tertiary, quaternary.

Rule 1 : Levels of structure — Primary: amino-acid sequence. Secondary: α-helix (right-handed, keratin) or β-pleated sheet (silk) held by H-bonds. Tertiary: 3-D folding by disulphide (S–S) and other bonds (myoglobin, enzymes). Quaternary: several subunits (haemoglobin).

  • Easy : Four levels: 1° sequence → 2° helix/sheet → 3° folding → 4° subunits.
  • Medium : A functional protein has a specific 3-D shape.
  • Exam-type (CET) : Basic protein (histone) is a cation at pH 7.4; acidic (blood proteins) an anion.

Rule 2 : Classification of proteins — Simple: only amino acids (albumin, histone, globulin). Conjugated: protein + prosthetic group – haemoglobin (globin + haem), nucleoprotein, glycoprotein, mucoprotein, lipoprotein. Derived: from hydrolysis (metaproteins, peptones).

  • Easy : Egg white = albumin (coagulates on heating).
  • Medium : Haem = iron pigment; globin = protein.
  • Exam-type (CET) : Peptones and metaproteins are not natural; they are derived.
Remember

Peptide bond; 20 amino acids; 4 structural levels; Hb = conjugated + quaternary.

Common mistake and CET trap

‘Peptide bond between –OH and –OH’ is wrong (–COOH and –NH₂). Trap: ‘Hb is simple’ is wrong.

Shortcut

Memory clue : "1-2-3-4: Order → Helix → Fold → Subunits".

Spot the difference

TypeExampleKey
SimpleAlbuminOnly amino acids
ConjugatedHaemoglobin+ prosthetic group
DerivedPeptoneFrom hydrolysis

Practice questions

Easy
  1. 1What is a peptide bond?
  2. 2How many amino acids?
  3. 3What is primary structure?
Medium
  1. 4What stabilises an α-helix?
  2. 5Example of quaternary structure.
  3. 6What is a prosthetic group?
Challenging
  1. 7Simple vs conjugated.
  2. 8What is the isoelectric point?
Show answers (try them yourself first)
  1. 1Bond between –COOH of one and –NH₂ of another amino acid.
  2. 220.
  3. 3Linear sequence of amino acids.
  4. 4Hydrogen bonds.
  5. 5Haemoglobin.
  6. 6Non-protein part of a conjugated protein (e.g. haem).
  7. 7Only amino acids / protein + non-protein group.
  8. 8pH at which net charge of protein is zero.

Nucleic acids

From daily life

The recipe of our body is written in DNA; RNA reads it to make proteins.

Simple definition

Nucleic acids = polymers of nucleotides (DNA and RNA). Nucleotide = pentose sugar + phosphate + nitrogen base; nucleoside = sugar + base. Bases: purines (A, G), pyrimidines (C, T, U).

DNA and RNAPhosphateSugar (5C)N-baseNucleotide = P + sugar + base | nucleoside = sugar + basePurines (2 rings): A, G | pyrimidines (1 ring): C, T, UAT=GC≡TA=CG≡AT=GC≡5′ ↔ 3′ antiparallel; A=T (2), G≡C (3 H-bonds)Watson–Crick; Chargaff: A=T, G=CRNAsingle strand; ribose; U (no T)mRNA : message (cistron)rRNA : ribosome (80–90%)tRNA: clover-leaf; anticodonDNA: deoxyribose + TDNA double (turn 34 Å, 3.4 Å rise)Miescher 1869 discovered nucleic acid; Fuelgen 1924: DNA in chromosomes

In the figure : Nucleotide, DNA double helix (A=T, G≡C) and the types of RNA.

Rule 1 : DNA — Watson–Crick: two antiparallel polynucleotide chains in a double helix; A–T (2 H-bonds), G–C (3). Sugar = deoxyribose. One turn 34 Å; base-pair spacing 3.4 Å; diameter 20 Å. Chargaff: purines = pyrimidines (A=T, G=C). Phosphodiester bonds link 5′ to 3′. Some viruses have single-stranded DNA (ϕX174).

  • Easy : A–T = 2, G–C = 3 H-bonds.
  • Medium : Watson and Crick did not run experiments; they analysed Franklin's and Wilkins' data.
  • Exam-type (CET) : DNA is in nucleus, mitochondria and chloroplasts.

Rule 2 : RNA — Single strand; ribose; U instead of T; genetic material in some viruses (TMV). Three types: mRNA (message; cistron; ~3%), rRNA (50–60% of ribosome; ~80–90% of cell RNA), tRNA (70–80 nucleotides; clover-leaf; anticodon; amino acid at the 3′ end).

  • Easy : DNA: deoxyribose + T; RNA: ribose + U.
  • Medium : Anticodon (tRNA) pairs with codon (mRNA).
  • Exam-type (CET) : Miescher (1869) isolated nucleic acid from pus cells.
Remember

DNA: double, T, deoxyribose; RNA: single, U, ribose; A–T 2, G–C 3.

Common mistake and CET trap

‘RNA has thymine’ is wrong. Trap: ‘G–C has 2 H-bonds’ is wrong (3).

Shortcut

Memory clue : "A–T = 2, G–C = 3; Pyrimidines = CUT (C, U, T)".

Spot the difference

PointDNARNA
StrandsDoubleSingle
SugarDeoxyriboseRibose
BaseA, T, G, CA, U, G, C

Practice questions

Easy
  1. 1What makes a nucleotide?
  2. 2Nucleoside vs nucleotide.
  3. 3Name purines and pyrimidines.
Medium
  1. 4H-bonds in A–T and G–C?
  2. 5Chargaff's rule.
  3. 6Three types of RNA.
Challenging
  1. 7Shape of tRNA and anticodon.
  2. 8Three differences between DNA and RNA.
Show answers (try them yourself first)
  1. 1Sugar + phosphate + nitrogen base.
  2. 2Nucleoside lacks phosphate.
  3. 3Purines A, G; pyrimidines C, T, U.
  4. 42 and 3.
  5. 5A=T and G=C (purine = pyrimidine).
  6. 6mRNA, rRNA, tRNA.
  7. 7Clover-leaf; 3 nucleotides pairing with the mRNA codon.
  8. 8Strands double/single; sugar deoxyribose/ribose; T / U.

Enzymes: nature, classification and mechanism

From daily life

A spoon of starter turns milk into curd; similarly a little enzyme speeds up many reactions yet remains unchanged.

Simple definition

Enzyme = biocatalyst (mostly protein; ribozymes = RNA). Acts on a substrate at its active site. Buchner coined ‘enzyme’ (Gk en + zyme = in yeast).

Enzyme action and the six classesLock and KeyenzymeFischer 1894: rigid, fixed active siteInduced FitEE–SKoshland 1959: substrate reshapes the siteApoenzyme (protein) + prosthetic group = holoenzymeCo-enzyme (organic, e.g. NAD, FMN) | co-factor (metal ions: Mg, Fe, Zn)1 OxidoreductasesH/O transfer2 Transferasesgroup transfer3 Hydrolaseshydrolysis4 Lyasesremove group, leave double bond5 Isomerasesrearrangement6 Ligasesjoin using ATPEnzyme = protein(ribozyme = RNA)Buchner: term ‘enzyme’

In the figure : Lock-and-key and induced-fit; holoenzyme; the six enzyme classes.

Rule 1 : Nature and properties — Apoenzyme (protein) + prosthetic group = holoenzyme; co-enzymes (organic: NAD, FMN) and co-factors (metal ions: Mg, Fe, Zn). Properties: protein, 3-D shape, catalytic, specific, sensitive to temperature and pH. Endo- and exo-enzymes. Naming: substrate + -ase (protease, sucrase).

  • Easy : Papain from papaya; bromelain from pineapple.
  • Medium : Sucrase hydrolyses about 100,000 times its own weight of sucrose.
  • Exam-type (CET) : Catalase co-factor Fe; peptidases Mn.

Rule 2 : Classification and mechanism — Six classes: Oxidoreductases (alcohol dehydrogenase), Transferases (glucokinase), Hydrolases (amylase, sucrase), Lyases (decarboxylase), Isomerases, Ligases (need ATP). Mechanism: substrate → active site → enzyme–substrate complex → product. Lock-and-key (Fischer 1894) and induced fit (Koshland 1959; more accepted).

  • Easy : OTHLIL = Oxido, Trans, Hydro, Lyases, Iso, Ligases.
  • Medium : Lock = enzyme; key = substrate.
  • Exam-type (CET) : Induced fit: flexible active site reshaped by the substrate.
Remember

Holoenzyme = apoenzyme + cofactor; 6 classes; induced fit is more accepted.

Common mistake and CET trap

‘All enzymes are proteins’ – ribozyme is an exception. Trap: ‘lock-and-key is flexible’ is wrong.

Shortcut

Memory clue : "OTHLIL = 1 Oxido, 2 Trans, 3 Hydro, 4 Lyase, 5 Iso, 6 Ligase".

Spot the difference

ClassReactionExample
HydrolasesHydrolysisAmylase
LigasesJoin with ATPPyruvate carboxylase
IsomerasesRearrangementXylose isomerase

Practice questions

Easy
  1. 1What is an enzyme?
  2. 2Apoenzyme vs holoenzyme.
  3. 3Co-enzyme and co-factor.
Medium
  1. 4Name the six enzyme classes.
  2. 5Which class is amylase?
  3. 6Who proposed lock-and-key?
Challenging
  1. 7What happens in induced fit?
  2. 8What is an active site?
Show answers (try them yourself first)
  1. 1A biocatalyst (mostly protein).
  2. 2Protein part / protein + prosthetic group.
  3. 3Organic (NAD) / metal ion (Mg).
  4. 4Oxidoreductases, transferases, hydrolases, lyases, isomerases, ligases.
  5. 5Hydrolases.
  6. 6Emil Fischer (1894).
  7. 7The substrate reshapes the active site.
  8. 8Region of the enzyme that binds the substrate.

Factors affecting enzymes, metabolism and secondary metabolites

From daily life

Dough ferments faster in summer yet curd spoils with too much heat; enzymes need the right temperature and pH.

Simple definition

Enzyme activity is affected by substrate concentration, enzyme concentration, temperature, pH, co-enzymes/activators/inhibitors. Metabolism = sum of all chemical reactions: catabolism + anabolism. Secondary metabolites = molecules not essential for growth but useful.

Factors on enzyme action and metabolism[S]KmVmax/2Substrate°C37°CTemperaturepH29.5pHpepsin = 2 | trypsin = 9.5inactive at 4°C; denatured at 60–70°CCatabolism: big → small, ATP madeAnabolism: small → big, ATP used⇄Metabolic pool: reservoir of molecules; carbohydrate ↔ fat interconversionSecondary metabolites: terpenes, phenolics, nitrogen compounds (alkaloids)Morphine (Papaver) = first alkaloid; tannins; drugs, preservatives

In the figure : Graphs for substrate, temperature and pH; catabolism/anabolism and secondary metabolites.

Live figure

Factors affecting enzymes, metabolism and secondary metabolites

In the app you can move this figure with your finger.

Open in the app

Rule 1 : Factors — Substrate: velocity rises up to Vmax – rectangular hyperbola. Km (Michaelis–Menten) = substrate concentration at Vmax/2; low Km = high affinity. Enzyme: more enzyme, higher rate. Temperature: most enzymes work best at 20–35°C (about 37°C in the human body); they denature fast above 40°C and are destroyed at 60–70°C; inactive (temporarily) at 4°C. pH: pepsin 2, trypsin 9.5. Inhibitors slow, activators speed up.

  • Easy : Low Km means strong enzyme–substrate binding.
  • Medium : Cold does not destroy an enzyme; heat does.
  • Exam-type (CET) : Catalase in potato + H₂O₂ = bubbles; boiled potato = none.

Rule 2 : Metabolism and secondary metabolites — Catabolism: complex → simple, ATP released (starch → glucose). Anabolism: simple → complex, energy used (glucose → glycogen). Metabolic pool: reservoir of cell molecules; carbohydrates ↔ fats. Secondary metabolites: terpenes, phenolics, nitrogen compounds (alkaloids); e.g. morphine (Papaver somniferum), tannins; drugs, flavour, food preservatives.

  • Easy : Catabolism = breaking; anabolism = building.
  • Medium : Morphine = first alkaloid isolated.
  • Exam-type (CET) : Glucosinolates = cabbage flavour and pest protection.
Remember

Km = Vmax/2; human enzymes optimum 37°C; pepsin 2, trypsin 9.5; catabolism makes ATP, anabolism uses ATP.

Common mistake and CET trap

‘High Km = high affinity’ is wrong (opposite). Trap: ‘anabolism releases energy’ is wrong.

Shortcut

Memory clue : "Low Km = more love (affinity); Catabolism = Cut, Anabolism = Assemble".

Spot the difference

PointCatabolismAnabolism
ActionBreakingBuilding
EnergyATP releasedATP used
ExampleStarch → glucoseGlucose → glycogen

Practice questions

Easy
  1. 1Optimum temperature?
  2. 2Optimum pH of pepsin and trypsin.
  3. 3What is Km?
Medium
  1. 4What does low Km show?
  2. 5Inhibitor vs activator.
  3. 6One example each of catabolism and anabolism.
Challenging
  1. 7What is a metabolic pool?
  2. 8Two uses of secondary metabolites.
Show answers (try them yourself first)
  1. 1About 37°C.
  2. 22 and 9.5.
  3. 3Substrate concentration at Vmax/2.
  4. 4High affinity.
  5. 5Slows / increases activity.
  6. 6Starch → glucose; glucose → glycogen.
  7. 7Reservoir of cell molecules on which enzymes act.
  8. 8Drugs (morphine); food preservative/flavour.

Quick revision of the whole lesson

ConceptKey fact
DisaccharidesSucrose G+F (non-red); lactose G+Ga; maltose G+G
PolysaccharidesStarch α, glycogen α, cellulose β
LipidsTriglyceride = glycerol + 3 FA; phospholipid = membrane
ProteinsPeptide bond; 4 levels; Hb conjugated
Nucleic acidsA–T 2, G–C 3; RNA = U + ribose
Enzymes6 classes; induced fit; holoenzyme
Factors37°C; pepsin 2 / trypsin 9.5; Km = Vmax/2

🎯 Most important points for the exam

  • Components of sucrose, lactose, maltose.
  • Starch vs glycogen vs cellulose.
  • Four levels of protein structure.
  • DNA vs RNA; Chargaff's rule.
  • Six enzyme classes and induced fit.
  • Km, optimum temperature and pH.
Study mantra

Understand the concept → draw the figure → memorise the key points → solve questions yourself.