The document discusses the key macromolecules that are essential for life - carbohydrates, proteins, lipids, and nucleic acids. It provides details on their monomers, polymers, functions, examples, and structural organization. The four macromolecules are large molecules formed by polymerization of smaller subunits. They perform critical roles like energy storage, structure, catalysis and information transfer in living organisms.

1. The ingredients for life

2. Very large molecules commonly created by polymerization
of smaller subunits (monomers)
Monomers: individual constituent molecules of
macromolecules.

3. Carbohydrates
Proteins Conventional
Nucleic acids
Lipids

4. Macromolecules form supramolecular assemblies
(Ex. membrane) which in turn organize into
organelles, cells, tissues, organs & finally the whole
organisms.

5. “Hydrates of Carbon”
Polyhydroxyaldehyde/ketone or compounds which produce
them on hydrolysis
Held together by glycosidic bonds
Primarily composed of C, H and O.
Sugars are carbs that are soluble in water, & sweet to
taste
Empirical formula: CnH2nOn

6. Based on the number of subunits present:
Monosaccharides:
i. Aldoses based on functional group
ii. Ketoses
a) Triose, Tetrose, Pentose, etc. based on carbon atoms present.
Oligosaccharides:
• Disaccharide, trisaccharide, etc. based on monosaccharides
present.
Polysaccharides:
i. Homopolysaccharides Ex. glucans, fructosans, starch etc.
ii. Heteropolysaccharides Ex. Hyaluronic acid, etc.

7. It is a fast fuel for the body; 4 cal/g
Serve as precursors for fats, a.a. etc.
To store energy. Ex. Glycogen, etc.
 Structural component:
• Cellulose in plants
• Exoskeleton of some insects
• Cell wall of microorganisms
Cell growth, adhesion & fertilisaion

8. Organic substance relatively insoluble in water,
soluble in org. solvents, related to fatty acids &
utilized by the living cells.
Lipids are not polymers
Mostly small mol.
Heterogeneous group of compounds (fats, oils, steroids,
waxes,etc.)
Animal fat is solid, while that of plants is liquid.
 C, H, O, N, S, P (O is vey less)
2 types of monomers: fatty acids & long chain alcohols

9. A. Simple lipids: esters of fatty acids with alcohols
a) Fats & oils (triacylglycerols)
b) Waxes
B. Complex lipids: in addition have groups such as
phosphate, nitrogen base, carbs, prot., etc.
a) Phospholipids: Based on alcohol pr. further divided as:
i. Glycolipids: Ex. Lecithin, cephalin, etc.
ii. Sphingophospholipids: Ex. spingomyelin, etc.
b) Glycolipids: alcohol is sphingosine; Ex. cerebrosides,
gangliosides, etc.
c) Lipoprotein
d) Others: sulfolipids, aminolipids & lipopolysaccharides

10. C. Derived lipids: Ex: glycerol, f.a., steroid
hormones, fat soluble vitamins, etc.
D. Miscellaneous lipids: Ex. Carotenoids, terpenes,
squalene, hydrocarbons such as pentacosane, etc.

11. Triacylglycerols are concentrated fuel reserve of the body
Phospholipids & cholesterol are constituents of membrane
str. & membrane permeability
Serve as a source of fat soluble vitamins
Steroid hormones & prostaglandins are cellular metabolic
regulators.
Protect internal organs, serve as insulating materials, and
give shape & smooth appearance to the body.

12. Carboxylic acids with hydrocarbon side chain
Mostly occurs in esterified forms as major
constituents of lipids.
F.a. of animal origin are much simpler
Simplest form of lipids

13. Even and odd carbon fatty acids:
• Most natural f.a. are even i.e. 14C – 20C
• Reason: biosynthesis of f.a. mainly occurs with
sequential addition of 2C units.
• Most common: palmitic acid (16C) & stearic acid
(18C)
• Among odd chain, propionic acid (3C) & valeric acid
(5C) are well known.

14. Saturated and unsaturated f.a.
• Saturated f.a. do not contain double bonds, while
unsaturated f.a. contain one or more double bonds.
• f.a. with one double bond are monounsaturated,
while 2 or more are polyunsaturated f.a. (PUFA)

15. Greek: ‘proterion’ – holding first place
 Berzelius => utmost important to life (1830)
Mulder => high mol. wt. nitrogen rich org.
substance pr. in animals and plants
 monomer: amino acids; bond: peptide
They show N & C-terminal
Most abundant org. mol.
Constitute 50% cellular dry wt.
Fundamental basis of str. & function of life

16. 300 a.a. occur in nature, only 20 a.a. are std. & are
reapeatedly found in str. of prot.
This is due to universal nature of genetic code
(controlled by DNA)
Group of org. compounds containing 2 functional
groups:
i. Amino group – basic (NH2)
ii. Carboxyl group – acidic (COOH)

17. A.a. is α – a.a. when both carboxyl as well as amino group
is attached to same carbon.
R – side chain, which varies in all 20 a.a.
A.a. mostly exist in ionized form

18. If a carbon is attached to 4 diff. groups, it is
asymmetric & therefore exhibits optical isomerism
If NH2 is on right hand side it is dextro, if it is on
left hand side it is laevo

19. Prot. Are polymers of L - α – a.a.
1. Pri. Str.: linear seq of a.a.; backbone; polypeptide
2. Sec. str.: spatial arrangement of prot. By twisting of
polypeptide chain
i. α – helix
ii. β- pleated sheet
3. Tertiary str.: 3D str. of a functional prot.
4. Quaternary str.: 2 or more polypeptide chains

21. Functional classification:
1. Structural: keratin (hair) & collagen (bone)
2. Enzymes: Hexokinase, pepsin, etc.
3. Transport: hemoglobin, serum, albumin.
4. Hormonal: insulin, GH.
5. Contractile: actin, myosin.
6. Storage: ovalbumin, etc.
7. Genetic: nucleoproteins
8. Defense: snake venoms, Igs.
9. Receptor: hormones, viruses.

22. Classification based on chemical nature &
solubility:
1. Simple: a.a.
2. Conjugated: a.a. + prosthetic group
3. Derived: degraded products

23. a) Globular proteins: spherical/oval; soluble in H2O &
other solvents and digestible.
i. Albumins: H2O & dil. salt sol. and coagulated
ii. Globulins: neutral & dil. salt sol.
iii. Glutelins: dil. acids & alkalis; mostly found in plants
iv. Prolamines: 70% alcohol
v. Histones: H2O & dil. acids; strongly basic
vi. Globins: not basic; NH4OH
vii. Protamines: NH4OH; strongly basic; in association with nucleic
acids Ex: sperm prot.
viii. Lectins: carb. binding prot.; interaction between cell & prot.

24. b) Fibrous proteins: fiber like prot., insoluble in water,
& resistant to digestion. Albuminoid or
scleroprotein (predominant)
i. Collagens:
• Conn. tissue prot. lacking tryptophan
• On boiling with H2O/dil. acid, yield gelatin (soluble & digestible)
ii. Elastin: elastic tissues (tendons & arteries)
iii. Keratin: pr. In exoskeletal str. (horns, hairs, etc.)

25. a) Nucleoproteins: nucleic acid; ex. nucleohistones
b) Glycoproteins: carb. (>4% of prot); ex. mucin(saliva)
c) Lipoproteins: lipids; ex. Serum lipoprot.
d) Phosphoproteins: phosphoric acid; ex. caesin
e) Chromoproteins: coloured; ex. haemoglobin
f) Metalloproteins: metal ions (Fe, Cu,etc.); ex.
Ceruloplasmin (Cu), etc.

26. a. Primary derived protein: first product of hydrolysis
i. Coagulated: denatured prot. (heat, acids, alkalies, etc.); ex.
coaguated albumin (egg white)
ii. Proteans: earliest product (enzymes, dil. acids,etc.); insoluble in
water; ex. fibrin
iii. Metaproteins: second stage products (slightly stronger acids &
alkalies); acid & alkali metaprot.
b. Secondary derived protein: progressive hydrolytic products of
hydrolysis
i. Proteoses
ii. Peptones
iii. Polypeptides
iv. Peptides

27. Nucleic acids are macromol. composed of many
monomers, called nucleotides.
Discovered by Johann Friedrich Meischer (1869)
Two types: DNA & RNA
DNA contains genetic material (Avery, Macleod &
MacCarty)

28. Composed of a nitrogen base, pentose sugar &
phosphate
Functions:
1. Str. components of some coenzymes of B – complex vit. (e.g. FAD,
NAD+)
2. Energy reactions of the cell
3. Control of metabolic reaction
Nucleoside: nitrogen + sugar
base

29.  Aromatic heterocyclic compounds
Purines are numbered anti-clock wise, while pyrimidines
are numbered clockwise
Purines: adenine (A) & guanine (G)
Pyrimidine: thymine (T), cytosine (C), Uracil (U)

30. Five carbon monosaccharides (pentose)
RNA => D-ribose
DNA => D-deoxyribose

31. Polymers of deoxyribosenucleotides
Monomeric units: dAMP, dGMP, etc.
Chargaff’s rule: molar equivalence between the
purines and pyrimidines in DNA
Watson and Crick model (1953) [B-DNA]
1. Right handed double helix
2. Width = 2nm
3. Each turn = 3.4nm, with 10 pairs, therefore distance
between each pair 0.34nm
4. Deoxyribose phosphate backbone (3’-5’ phosphodiester
bond); hydrophilic; N-bases are stacked inside & are
hydrophobic

32. Both the strands are complementary to
each other due to base pairing.
Two strands are held together by
hydrogen bonds. G-C bond is 50%
stronger than A-T
Genetic info resides on one of 2 strands,
which is known as sense or template
strand.
Major and minor groves are pr.

33. Variations of conformation of nucleotides
6 diff. forms: A, B, C, D, E, & Z. [B, A & Z are imp]
B-form => Watson & Crick; most predominant
under normal physiological conditions
A- form=> right handed helix; 11bp per turn;
tilting of bps by 20o away from central axis
Z- form => left handed helix; 12bps per turn;
strands move in a zig-zag fashion
Transition between helical forms significant in
regulating gene expression

35. Chemical basis of hereditary (genetic reserve)
Maintains identity of species
DNA controls every aspect of cellular function
DNA is organized into genes
Genes => fundamental units of genetic info
Central dogma

36. RNA is a polymer of ribonucleotides held together by
3’-5’ phosphodiester bridges.
Pentose sugar is ribose
RNA contains the pyrimidine uracil instead of thymine
It is usually a single stranded polynucleotide
Chargaff’s rule is not obeyed
Orcinol can stain RNA due to pr. of ribose
Alkali can hydrolyse RNA to 2’-3’ cyclic diesters. Due
to OH at 2’ position.

37. 1. Messenger RNA
2. Transfer RNA
3. Ribosomal RNA

38. Biochemistry by U. Satyanarayana & U.
Chakrapani
11th standard biology Maharashtra State board
Crash course (youtube channel)