· The collection of various types of molecules in a cell is termed a cellular pool.
· A cellular pool consists of organic and inorganic compounds.
· A cellular pool provides materials for the structure and functions of the cell. The constancy of the pool is maintained by the intake and elimination of specific molecules.
(A) Organic compounds – Carbohydrates, Proteins, Lipids and Nucleic acids.
(B) Inorganic compounds – Water, Minerals and Salts.
A. MICROMOLECULES
B. MACROMOLECULES
· Carbohydrates literally means "hydrate of carbon", hydrogen and oxygen generally occurring in the ratio of 2:1.
· Most abundant organic substance in nature.
· They are mainly compounds of carbon, hydrogen and oxygen.
· General formula of carbohydrates is Cn(H2O)n.
· They are often called saccharides (compounds containing sugar).
· Carbohydrates are produced by green plants during photosynthesis.
(A) Organic compounds – Carbohydrates, Proteins, Lipids and Nucleic acids.
(B) Inorganic compounds – Water, Minerals and Salts.
Organic Compounds
They are of two types:A. MICROMOLECULES
· These are small and simple molecules with low molecular weight.
· They have smaller molecular configurations and higher solubility.
E.g. Monosaccharides, Disaccharides, Unsaturated and Saturated fatty acids, Amino acids and Nucleotides.
B. MACROMOLECULES
· Large complex molecules with high molecular weight, generally formed by the polymerization of a large number of small molecules.
e.g. Polysaccharides, Lipids, Proteins, DNA and RNA molecules.
e.g. Polysaccharides, Lipids, Proteins, DNA and RNA molecules.
CARBOHYDRATES
· Carbohydrates may be defined as 'polyhydroxy aldehydes or ketones' or compounds that produce them on hydrolysis.· Carbohydrates literally means "hydrate of carbon", hydrogen and oxygen generally occurring in the ratio of 2:1.
· Most abundant organic substance in nature.
· They are mainly compounds of carbon, hydrogen and oxygen.
· General formula of carbohydrates is Cn(H2O)n.
· They are often called saccharides (compounds containing sugar).
· Carbohydrates are produced by green plants during photosynthesis.
They are divided into the following groups:
(1) Monosaccharides
(2) Disaccharides
(3) Polysaccharides
FUNCTIONS of Carbohydrate:
· Source of energy (gives about 4 cal/gm of energy).
· Serve as the storage form of energy (glycogen).
· Glucose and other sugars form fat, amino acids.
· Fructose is common fruit sugar and lactose is a natural sugar present in milk
1. Monosaccharides (Greek: mono – one)
· Often referred to as simple sugar.
· They are the smallest unit or building block of carbohydrates.
· Simplest form of carbohydrate which cannot be hydrolysed into a simpler form.
· Can be represented by general formula CnH2nOn.
· They are composed of 3 – 7 carbon atoms and are classified according to the number of the carbon atom.
(b) KETOSES – Monosaccharide having ketone(> C = O) functional group.
Note: Glucose is aldohexose while fructose is ketohexose.
· Sugar having free aldehyde and ketone group can reduce Cu++ to Cu+ form. So they are called reducing sugars.
Note: Monosaccharides and disaccharides are reducing sugars except sucrose which is non-reducing.
· Glucose (dextrose or grape sugar or aldohexose) is the most abundant monosaccharide found in nature.
· Glucose (C6H12O6) is the constituent of polysaccharides (starch, glycogen, cellulose) and disaccharides (maltose, lactose, sucrose).
· Glucose the "sugar fuel" of life is excreted in the urine in diabetes. It is the structural unit of cellulose in plants.
· Glucose helps in the synthesis of fats and amino acids.
· Benedict's (most commonly) and Fehling's tests are done to detect the presence of glucose in urine.
· Glucose is stored as glycogen in the liver and muscle in human beings.
· Major structural component of disaccharides and polysaccharides.
· Glucose and fructose act as the source of energy when oxidized during respiration.
· In the human body, measurement of blood sugar refers to the measurement of blood glucose level.
· Glucose is the commonest respiratory substrate and the main cellular fuel of the body.
· Proteins are the polymer of amino acids linked together by a peptide bond.
· Since 4 different groups are attached to the carbon atom it is called asymmetric or chiral carbon.
· They are the monomers of protein or basic units or building blocks of protein.
· Amino acids are colourless crystalline solids that are generally soluble in water and insoluble in organic solvents.
· Amino acids are converted to vitamins, hormones etc. and the carbon chain of amino acids may be converted into glucose after the removal of the amino group.
· About 20 naturally occurring amino acids are known.
· Nutritionally amino acids are divided into essential and non-essential.
· Proline is the imino acid.
· Glycine is the simplest amino acid.
· Lysine and threonine are deficient in cereals.
· Methionine is deficient in pulses.
· Tryptophan is deficient in maize.
· Plant proteins are biologically incomplete and they do not contain essential amino acids.
· Proteins are synthesized by RNA by the process of translation and ribosomes are associated with protein synthesis.
· Hydrolysis of protein yields amino acids.
· Proteins are often called polypeptide structures since they are formed by a large no. of amino acids linked together by a peptide bond.
b. Classification of Protein-based upon their Chemical Nature
(a) Simple protein – formed of the peptide chain and yields amino acid on hydrolysis. E.g. albumin, globulin
(b) Conjugated proteins – Protein formed in combination with non-proteinous substances.
(c) Derived proteins – are formed by partial hydrolysis of simple and conjugated proteins.
2. Globular protein:
· This type of protein has molecules folded into compact units which often acquire spheroidal shape.
· These are soluble in water, dilute acids and alkalies.
Eg: Insulin, Haemoglobin.
e. Various Functions of Proteins
· Building block or structural function e.g. Keratin of hair, Collagen of bone.
· Enzymatic or catalytic function e.g. Hexokinase, Pepsin, Catalase.
· Transport proteins – Haemoglobin, Serum albumin
· Hormonal proteins – Insulin, growth hormone
· Genetic proteins – Nucleoproteins
· Defense protein – Antibodies or Immunoglobins
· Contractile protein – Actin, Myosin
A. Fatty acids (R – COOH)
· Fatty acids are carboxylic acids with hydrocarbon side chains. They are the simplest form of lipids.
· They are either saturated (all carbon-carbon bonds are single bonds) or unsaturated (with one or more double bonds in the hydrocarbon chain).
b. Unsaturated fatty acids have a general formula CnH2n–2O2
· Blood cholesterol level is increased by saturated fatty acids and decreases by unsaturated fatty acids, so unsaturated fatty acids like sunflower oil, coconut oil are preferred.
· Hydrogenation is the process of conversion of vegetable oils (unsaturated fatty acids) to Vanaspati ghee (saturated fatty acids).
2. Complex (Compound lipids) or conjugated lipids
3. Derived lipids – They are the derivatives obtained by the hydrolysis of simple and compound lipids
· Triglycerides are the esters of fatty acids with glycerol.
c. Functions of Lipids
· Lipids are the source of energy (1 gm of fat provides 9 kcal energy).
· They are the fuel reserve of the body.
· Fat deposited in the subcutaneous tissue acts as an insulator.
· Lipids act as a solvent for fat-soluble Vit. A, D, E & K.
· Vit. D is derived from cholesterol.
· Lipoproteins (lipid + protein) are the carrier of lipids in the body.
· Bile salts are the modified cholesterol required for the digestion of lipid.
· Vitamins can be:
1. Water-soluble: Vit. B complex and Vit. C
2. Fat-soluble: Vitamin A, D, E and K
A. Fat-soluble Vitamins
a. Vitamin-A
· Daily requirement 2 gm
· Discovered by MacCallum.
g. Vitamin B12
· Daily requirement trace
· Also known as Cyanocobalmin.
· Chemically, it is made up of a porphyrin head without a phytol tail.
· Isoprene and its derivatives are joined in various combinations to produce substances such as Vitamin A, Coenzyme Q and carotenoids.
· Menthol and camphor are the common terpenes
· Nucleic acids are the polymer of nucleotides.
· Each nucleotide consists of
Two types of pentose sugar – Ribose sugar in RNA and Deoxyribose sugar in DNA.
· Nitrogen bases may be purine or pyrimidine.
· Purines – Adenine (A) and Guanine (G)
· Pyrimidines – Cytosine (C), Thymine (T) and Uracil (U)
· Uracil is present in RNA only in place of thymine.
· Two nucleotides are joined together by a Phosphodiester bond.
· Nucleoside – formed by the combination of sugar and a base. E.g. Ribonucleosides & Deoxyribonucleosides.
· Nucleotide = Nucleoside + Phosphate group
· Complementary bases are
· Adenine & Thymine (A = T) by two hydrogen bonds.
· Cytosine & Guanine (C ≋ G) by three hydrogen bonds.
· Other nucleotides are AMP, ADP, ATP, NAD, NADP, FMN, FAD.
(1) Monosaccharides
(2) Disaccharides
(3) Polysaccharides
FUNCTIONS of Carbohydrate:
· Source of energy (gives about 4 cal/gm of energy).
· Serve as the storage form of energy (glycogen).
· Glucose and other sugars form fat, amino acids.
· Fructose is common fruit sugar and lactose is a natural sugar present in milk
1. Monosaccharides (Greek: mono – one)
· Often referred to as simple sugar.
· They are the smallest unit or building block of carbohydrates.
· Simplest form of carbohydrate which cannot be hydrolysed into a simpler form.
· Can be represented by general formula CnH2nOn.
· They are composed of 3 – 7 carbon atoms and are classified according to the number of the carbon atom.
E.g. Triose, Tetrose, Pentose, Hexose and Heptoses.
Two types of Monosaccharides:
(a) ALDOSES – Monosaccharides having aldehyde (– CHO) functional group.
(a) ALDOSES – Monosaccharides having aldehyde (– CHO) functional group.
E.g. glucose, glyceraldehyde.
(b) KETOSES – Monosaccharide having ketone(> C = O) functional group.
E.g. Fructose, Dihydroxyacetone.
Note: Glucose is aldohexose while fructose is ketohexose.
· Sugar having free aldehyde and ketone group can reduce Cu++ to Cu+ form. So they are called reducing sugars.
Note: Monosaccharides and disaccharides are reducing sugars except sucrose which is non-reducing.
· Glucose (dextrose or grape sugar or aldohexose) is the most abundant monosaccharide found in nature.
· Glucose (C6H12O6) is the constituent of polysaccharides (starch, glycogen, cellulose) and disaccharides (maltose, lactose, sucrose).
· Glucose the "sugar fuel" of life is excreted in the urine in diabetes. It is the structural unit of cellulose in plants.
· Glucose helps in the synthesis of fats and amino acids.
· Benedict's (most commonly) and Fehling's tests are done to detect the presence of glucose in urine.
· Glucose is stored as glycogen in the liver and muscle in human beings.
· Major structural component of disaccharides and polysaccharides.
· Glucose and fructose act as the source of energy when oxidized during respiration.
· In the human body, measurement of blood sugar refers to the measurement of blood glucose level.
· Glucose is the commonest respiratory substrate and the main cellular fuel of the body.
· Fructose (C6H12O6) is also called Fruit sugar (sugar in fruits, honey and nectar). It forms the structural component of sucrose.
· Ribose (pentose) is a component of RNA, ATP and NAD.
· Deoxyribose (pentose) is a sugar present in DNA.
· Hexose (Galactose) is the sugar present in milk.
· Fructose (Hexose) is often called levulose and it is the sweetest among naturally occurring sugar.
· Ribose (pentose) is a component of RNA, ATP and NAD.
· Deoxyribose (pentose) is a sugar present in DNA.
· Hexose (Galactose) is the sugar present in milk.
· Fructose (Hexose) is often called levulose and it is the sweetest among naturally occurring sugar.
2. Oligosaccharides (Oligos – few)
· Oligodaccharides are formed by the condensation of 2 – 10 Monosaccharides molecules.
· Oligosaccharides may be disaccharides (sucrose, maltose, lactose), trisaccharides (raffinose), tetrasaccharides etc. or polysaccharides.
· Oligosaccharides are commonly sweet in taste, water-soluble and can be hydrolysed with acid but not a base.
· Upon hydrolysis oligosaccharides give rise to monosaccharides.
a. Disaccharides
· Simplest oligosaccharides are made up of 2 molecules of monosaccharides joined together by a glycosidic link.
· Oligodaccharides are formed by the condensation of 2 – 10 Monosaccharides molecules.
· Oligosaccharides may be disaccharides (sucrose, maltose, lactose), trisaccharides (raffinose), tetrasaccharides etc. or polysaccharides.
· Oligosaccharides are commonly sweet in taste, water-soluble and can be hydrolysed with acid but not a base.
· Upon hydrolysis oligosaccharides give rise to monosaccharides.
a. Disaccharides
· Simplest oligosaccharides are made up of 2 molecules of monosaccharides joined together by a glycosidic link.
E.g. Maltose, Lactose, Sucrose.
ENTRANCE EXAM TIPS!
· Maltose or Malt sugar is an intermediate in the digestion of starch to glucose.
Maltose → glucose + glucose
· Lactose is the sugar present in milk.
Lactose → glucose + galactose
· Maltose or Malt sugar is an intermediate in the digestion of starch to glucose.
Maltose → glucose + glucose
· Lactose is the sugar present in milk.
Lactose → glucose + galactose
· Sucrose (cane sugar or table sugar) is the storage material for sugar bit and sugarcane.
Sucrose → glucose + fructose
Sucrose → glucose + fructose
· Carbohydrate is transported in the phloem tissue of the plant in the form of sucrose.
· Raffinose is a common trisaccharide found in plants, which on hydrolysis gives rise to a molecule of each, glucose, fructose and galactose.
· Raffinose is a common trisaccharide found in plants, which on hydrolysis gives rise to a molecule of each, glucose, fructose and galactose.
3. Polysaccharides
· These are the complex molecules made up of condensation of a large number of monosaccharides.
· Starch is found as storage food in plants and glycogen as storage food in animals.
· These are insoluble carbohydrates and are considered to be non-sugars. E.g. Glycogen, starch, cellulose, dextrin, insulin etc.
· Starch a polymer of glucose is the major food reserve in plants which is made up of water-soluble amylose and water-insoluble amylopectin.
· Inulin (found in the root of Dahlia) is a polymer of fructose or fructosan, which is used for assessing kidney function tests through the measurement of GFR (Glomerular filtration rate).
· Insulin – a hormone, a protein.
· Dextrins are the breakdown products of starch by enzyme amylase or dilute acids.
· Glycogen is the animal reserve in animals so it is called animal starch.
· Cellulose occurs exclusively in plants and it is the most abundant organic substance in the plant kingdom. It is composed of β – D glucose units linked together by β (1 – 4) glycosidic bond.
· Chitin is a polysaccharide of glucose found in the exoskeleton of some insects and crustaceans.
· Starch can be detected by using a starch iodide test.
· Agar-agar is a polymer of galactose, which is used to solidify culture media, obtained from Red Algae.
· Callose is an amorphous polymer of glucose.
ENTRANCE EXAM TIPS!
Sucrose → glucose + fructose
· These are the complex molecules made up of condensation of a large number of monosaccharides.
· Starch is found as storage food in plants and glycogen as storage food in animals.
· These are insoluble carbohydrates and are considered to be non-sugars. E.g. Glycogen, starch, cellulose, dextrin, insulin etc.
· Starch a polymer of glucose is the major food reserve in plants which is made up of water-soluble amylose and water-insoluble amylopectin.
· Inulin (found in the root of Dahlia) is a polymer of fructose or fructosan, which is used for assessing kidney function tests through the measurement of GFR (Glomerular filtration rate).
· Insulin – a hormone, a protein.
· Dextrins are the breakdown products of starch by enzyme amylase or dilute acids.
· Glycogen is the animal reserve in animals so it is called animal starch.
· Cellulose occurs exclusively in plants and it is the most abundant organic substance in the plant kingdom. It is composed of β – D glucose units linked together by β (1 – 4) glycosidic bond.
· Chitin is a polysaccharide of glucose found in the exoskeleton of some insects and crustaceans.
· Starch can be detected by using a starch iodide test.
· Agar-agar is a polymer of galactose, which is used to solidify culture media, obtained from Red Algae.
· Callose is an amorphous polymer of glucose.
ENTRANCE EXAM TIPS!
Sucrose → glucose + fructose
Glucose → Ethyl alcohol + CO2
Starch → maltose
Maltose → glucose
· Saccharification - Conversion of starch into maltose
· Invert sugar - Sucrose
· Cellulose is the important constituent of the plant cell walls.
· Invert sugar - Sucrose
· Cellulose is the important constituent of the plant cell walls.
AMINO ACIDS & PROTEINS
· Proteins are the most abundant organic molecule in the living system.· Proteins are the polymer of amino acids linked together by a peptide bond.
1. Amino Acids
· Group of organic compounds containing two functional groups (amino and carboxyl).
· Group of organic compounds containing two functional groups (amino and carboxyl).
· Amino group (– NH2), Carboxyl group (– COOH).
H2N
|
R – C – H (R = alkyl group)
|
COOH
|
R – C – H (R = alkyl group)
|
COOH
· Since 4 different groups are attached to the carbon atom it is called asymmetric or chiral carbon.
· They are the monomers of protein or basic units or building blocks of protein.
· Amino acids are colourless crystalline solids that are generally soluble in water and insoluble in organic solvents.
· Amino acids are converted to vitamins, hormones etc. and the carbon chain of amino acids may be converted into glucose after the removal of the amino group.
· About 20 naturally occurring amino acids are known.
· Nutritionally amino acids are divided into essential and non-essential.
1. Essential amino acids are those amino acids that cannot be synthesized by our body so these amino acids must be supplied through diet.
· They are: PVT TIM HALL (Phenylalanine, Valine, Threonine, Tryptophan, Isoleucine, Methionine, Histidine, Arginine, Leucine, Lysine)
· Arginine and Histidine can be synthesized by adults but not by growing children so they are semi-essential amino acids.
· Arginine and Histidine can be synthesized by adults but not by growing children so they are semi-essential amino acids.
2. Non-essential amino acids can be synthesized by our body and they are not required in the diet.
· They are Glycine, alanine, serine, cysteine, aspartate, asparagines, glutamate, glutamine, tyrosine & praline.
· Proline is the imino acid.
· Glycine is the simplest amino acid.
· Lysine and threonine are deficient in cereals.
· Methionine is deficient in pulses.
· Tryptophan is deficient in maize.
· Plant proteins are biologically incomplete and they do not contain essential amino acids.
· Proteins are synthesized by RNA by the process of translation and ribosomes are associated with protein synthesis.
· Hydrolysis of protein yields amino acids.
· Proteins are often called polypeptide structures since they are formed by a large no. of amino acids linked together by a peptide bond.
· Peptide bond is a covalent bond between the carboxyl group of one amino acid and the amino group of another amino acid.
a. STRUCTURE OF PROTEINS
1. Primary structure – The linear sequence of amino acids forming the backbone of proteins (polypeptide).
2. Secondary structure – The spatial arrangement of protein by twisting of the polypeptide chain.
3. Tertiary structure – The three-dimensional structure of a functional protein.
4. Quaternary structure – Some of the proteins are composed of two or more polypeptide chains referred to as subunits.
· Secondary structure of the protein is stabilized by a Hydrogen bond.
· Tertiary structure of the protein is 3 dimensional in shape which is stabilized by disulphide bonds, hydrogen bonds, Vander Waals, electrostatic and hydrophobic effect.
a. STRUCTURE OF PROTEINS
1. Primary structure – The linear sequence of amino acids forming the backbone of proteins (polypeptide).
2. Secondary structure – The spatial arrangement of protein by twisting of the polypeptide chain.
3. Tertiary structure – The three-dimensional structure of a functional protein.
4. Quaternary structure – Some of the proteins are composed of two or more polypeptide chains referred to as subunits.
· Secondary structure of the protein is stabilized by a Hydrogen bond.
· Tertiary structure of the protein is 3 dimensional in shape which is stabilized by disulphide bonds, hydrogen bonds, Vander Waals, electrostatic and hydrophobic effect.
b. Classification of Protein-based upon their Chemical Nature
(a) Simple protein – formed of the peptide chain and yields amino acid on hydrolysis. E.g. albumin, globulin
(b) Conjugated proteins – Protein formed in combination with non-proteinous substances.
E.g. glycoproteins (combination of protein with glucose – saliva), lipoproteins (amino acids with lipid), nucleoprotein etc.
(c) Derived proteins – are formed by partial hydrolysis of simple and conjugated proteins.
E.g. peptones and proteoses
c. Classification of Protein-based upon their Functions
d. Classification of Protein-based upon their Shape & Function
1. Fibrous protein:
· These are thread-like molecules that lie side by side to form fibres.
· The various molecules are held together by Hydrogen bonds.
· These are insoluble in water but soluble in concentrated acids and alkalies.
Eg: Keratin of hair, nails, wood, myosin of muscles.
c. Classification of Protein-based upon their Functions
| Class of Protein | Function in the body | Examples |
|---|---|---|
| Structural | Provides structural components | Collagen, Keratin |
| Contractile | Move muscles | Myosin, Actin |
| Transport | Carry essential substances throughout the body | Haemoglobin, Lipoprotein |
| Storage | Store nutrients | Casein, ferritin |
| Hormone | Regulate body metabolism and nervous system | Insulin: Growth hormone |
| Enzyme | Catalyze biochemical reaction in the cells | Sucrase, Trypsin |
| Protection | Recognize and destroy foreign substances | Immunoglobulin |
d. Classification of Protein-based upon their Shape & Function
1. Fibrous protein:
· These are thread-like molecules that lie side by side to form fibres.
· The various molecules are held together by Hydrogen bonds.
· These are insoluble in water but soluble in concentrated acids and alkalies.
Eg: Keratin of hair, nails, wood, myosin of muscles.
2. Globular protein:
· This type of protein has molecules folded into compact units which often acquire spheroidal shape.
· These are soluble in water, dilute acids and alkalies.
Eg: Insulin, Haemoglobin.
e. Various Functions of Proteins
· Building block or structural function e.g. Keratin of hair, Collagen of bone.
· Enzymatic or catalytic function e.g. Hexokinase, Pepsin, Catalase.
· Transport proteins – Haemoglobin, Serum albumin
· Hormonal proteins – Insulin, growth hormone
· Genetic proteins – Nucleoproteins
· Defense protein – Antibodies or Immunoglobins
· Contractile protein – Actin, Myosin
LIPIDS
· (Greek: Lipos – fat)
· Lipids may be regarded as an organic substance insoluble in water, soluble in organic solvents (alcohol, ether etc.).
· They are the heterogeneous group of organic compounds made up of 'C', 'H' and 'O' but much less oxygen as compared to carbohydrates.
· True lipids are the esters of fatty acids and alcohol.
· Lipids may be regarded as an organic substance insoluble in water, soluble in organic solvents (alcohol, ether etc.).
· They are the heterogeneous group of organic compounds made up of 'C', 'H' and 'O' but much less oxygen as compared to carbohydrates.
· True lipids are the esters of fatty acids and alcohol.
A. Fatty acids (R – COOH)
· Fatty acids are carboxylic acids with hydrocarbon side chains. They are the simplest form of lipids.
· They are either saturated (all carbon-carbon bonds are single bonds) or unsaturated (with one or more double bonds in the hydrocarbon chain).
a. Saturated fatty acids have general formula CH3(CH2)nCOOH or CnH2nO2
E.g. Platinic acid, Stearic acid etc. and they melt at higher temperatures.
b. Unsaturated fatty acids have a general formula CnH2n–2O2
E.g. Oleic acid, Linoleic acid, Linolenic acid etc. and they have low melting points.
· Blood cholesterol level is increased by saturated fatty acids and decreases by unsaturated fatty acids, so unsaturated fatty acids like sunflower oil, coconut oil are preferred.
· Hydrogenation is the process of conversion of vegetable oils (unsaturated fatty acids) to Vanaspati ghee (saturated fatty acids).
· Since Vanaspati ghee is deficient in fat-soluble vitamins, it has to be fortified with Vit. A & D.
· Some polyunsaturated fatty acids cannot be synthesized in the body so they are called essential fatty acids.
· Some polyunsaturated fatty acids cannot be synthesized in the body so they are called essential fatty acids.
E.g. Linoleic acid, linolenic acid and Arachidonic acid
Differences Between Saturated & Unsaturated Fat
| Saturated Fat | Unsaturated Fat |
|---|---|
| No double bonds between carbons in the fatty acid tail | One or more double bonds between in carbon in acid fatty tail |
| The carbon Skeleton of fatty acid is bonded to the maximum number of hydrogens | Tail kinks at each C-C, so molecules do not pack closely enough to solidify at room tempt. |
| Usually a solid at room temperature | Usually a liquid at room temperature |
| Most animals fats | Most plant fats |
| Examples: bacon grease, lard and butter |
Examples: corn, peanut and olive oil |
b. Classification of Lipids
1. Simple lipids
1. Simple lipids
· Esters of fatty acids with alcohol E.g. fats, oils and waxes.
· Oils are rich in unsaturated fatty acids and liquid at room temperature whereas fats are rich in saturated fatty acids which are generally solid at room temperature.
· Oils are rich in unsaturated fatty acids and liquid at room temperature whereas fats are rich in saturated fatty acids which are generally solid at room temperature.
2. Complex (Compound lipids) or conjugated lipids
· Esters of fatty acids with alcohol-containing some additional groups like phosphate, nitrogen, base, carbohydrate, protein etc.
E.g. phospholipids, glycolipids, lipoprotein
E.g. phospholipids, glycolipids, lipoprotein
3. Derived lipids – They are the derivatives obtained by the hydrolysis of simple and compound lipids
E.g. steroids (cholesterol).
· Triglycerides are the esters of fatty acids with glycerol.
· Each glycerol possess 3 hydroxyl groups.
· Cholesterol is the precursor molecule of many sex hormones like testosterone, progesterone, cortisol etc.
· Cholesterol is the precursor molecule of many sex hormones like testosterone, progesterone, cortisol etc.
· Cholesterol on irradiation by UV rays forms Vitamin D which is necessary for the growth of bones.
· Waxes are the long chain of fatty acids with a long chain of alcohol, E.g. Bee wax (a combination of platinic acid and myricyl alcohol).
· Waxes are the long chain of fatty acids with a long chain of alcohol, E.g. Bee wax (a combination of platinic acid and myricyl alcohol).
· Excessive cholesterol intake causes an abnormal thickening of the wall of the blood vessels (Atherosclerosis) and it causes hypertension and increase blood pressure.
c. Functions of Lipids
· Lipids are the source of energy (1 gm of fat provides 9 kcal energy).
· They are the fuel reserve of the body.
· Fat deposited in the subcutaneous tissue acts as an insulator.
· Lipids act as a solvent for fat-soluble Vit. A, D, E & K.
· Vit. D is derived from cholesterol.
· Lipoproteins (lipid + protein) are the carrier of lipids in the body.
· Bile salts are the modified cholesterol required for the digestion of lipid.
VITAMINS
· These are potent organic substances that are required in minute quantities for optimum functioning of metabolic pathways and various body functions.· Vitamins can be:
1. Water-soluble: Vit. B complex and Vit. C
2. Fat-soluble: Vitamin A, D, E and K
A. Fat-soluble Vitamins
a. Vitamin-A
· Daily requirement 2 gm
· Discovered by MacCallum.
· Also known as Retinol and Antixeropthalmic vitamin.
· It is a vitamin for normal vision.
· It is an anti-infective vitamin.
· It is stored in the liver.
· Isomers of vitamin A are A1- Retinol for Vision & A2- Dehydro retinol, which is essential for epithelial lining and tear production.
Deficiency of Vitamin A causes
· Night Blindness: due to deficiency of A1, Also known as Nyctalopia.
· Xeropthalmia: Cornea becomes dry; Tear formation absent; Keratinization of conjunctiva starts. It may lead to total blindness.
· Keratomalesia: Keratinization and degeneration of cornea take place.
· Dermatosis- Skin becomes dry, scale-like.
· Keratinization: Keratinization of soft tissue takes place in the lining of the nasal chamber, trachea, bronchi. Source: carrot, papaya, mango, liver, egg, yolk, cod liver oil.
Deficiency of Vitamin A causes
· Night Blindness: due to deficiency of A1, Also known as Nyctalopia.
· Xeropthalmia: Cornea becomes dry; Tear formation absent; Keratinization of conjunctiva starts. It may lead to total blindness.
· Keratomalesia: Keratinization and degeneration of cornea take place.
· Dermatosis- Skin becomes dry, scale-like.
· Keratinization: Keratinization of soft tissue takes place in the lining of the nasal chamber, trachea, bronchi. Source: carrot, papaya, mango, liver, egg, yolk, cod liver oil.
b. Vitamin D
· Daily requirement 0.01 mg
· Also known as Calciferol, Anti-rickets vitamin and sunshine vitamin.
· Daily requirement 0.01 mg
· Also known as Calciferol, Anti-rickets vitamin and sunshine vitamin.
· It is necessary for bones and teeth.
· Regulate absorption of calcium and phosphorus.
· Best source is Cod liver oil.
· Other sources are Spleen, egg, milk.
· All are steroids.
Deficiency of Vitamin D causes
· Deficiency causes Rickets in children and Osteomalacia, softening of bones, in adults.
Deficiency of Vitamin D causes
· Deficiency causes Rickets in children and Osteomalacia, softening of bones, in adults.
c. Vitamin E
· Daily requirement 15 mg
· It is also known as Beauty Vitamin & Tocopherol.
· Daily requirement 15 mg
· It is also known as Beauty Vitamin & Tocopherol.
· It does not act with coenzyme.
· It is fertility vitamin.
· Deficiency cause sterility.
Source: Cottonseed oil, egg, muscle, green leaves.
Source: Cottonseed oil, egg, muscle, green leaves.
d. Vitamin K
· Daily requirement 0.07 m
· Also known as Napthoquinone or Phylloquinone
· Daily requirement 0.07 m
· Also known as Napthoquinone or Phylloquinone
· Vitamin for blood clotting and coagulation
· Anti-haemorrhagic vitamin.
Source: Carrot, Tomato, Liver, Cheese, Cabbage.
· Deficiency may cause delayed blood clotting.
Source: Carrot, Tomato, Liver, Cheese, Cabbage.
· Deficiency may cause delayed blood clotting.
B. Water Soluble Vitamins
a. Vitamin B1
· Daily requirement 1.2-1.4 mg
· Name B1 was given by Funk.
a. Vitamin B1
· Daily requirement 1.2-1.4 mg
· Name B1 was given by Funk.
· Anti neurotic factor.
· Also known as thiamine.
· Deficiency of Vit B1 causes beriberi.
· Symptoms of beriberi 1st observed by Admiral Takkari in sailors of Japan.
· Beriberi also known as dry beriberi in which loss of appetite, atrophy of muscles and paralysis of limbs may appear.
· Polyneuritis is wet beriberi in which loss of weight, paralyzing of wings and reduction in movement takes place.
b. Vitamin B2
· Daily requirement 1.4 mg
· Known as Vit. G or Riboflavin.
· Daily requirement 1.4 mg
· Known as Vit. G or Riboflavin.
· It is associated with the formation of FMN and FAD.
· It forms coenzyme FAD with phosphoric aid.
· Deficiency cause cheilosis (Angular stomatitis).
· Lips become red, swollen and cracks appear at the angle of the mouth.
Source: Liver, Cheese, Egg, Meat, Yeast.
Source: Liver, Cheese, Egg, Meat, Yeast.
c. Vitamin B3
· Daily requirement 1.3-1.8 mg
· Also known as an anti-pellagra factor, Vit. PP (Pellagra Preventing factor) or Niacin or Nicotinamide.
· Also known as an anti-pellagra factor, Vit. PP (Pellagra Preventing factor) or Niacin or Nicotinamide.
· PP factor is given by Gold burger.
· It forms essential components of NAD and NADP.
· Deficiency causes Pellagra.
· Deficiency causes Pellagra.
· Pellagra is also known as a 3D syndrome. D- Dermatitis (Redness of skin), D-Diarrhoea, D- Dementia (Mammary disorder).
Source: Liver, Kidney.
d. Vitamin B5
· Daily requirement 5-10 mg
· Also known as Pantothenic acid or yeast factor.
· Also known as Pantothenic acid or yeast factor.
· Active form is the constituent of coenzyme A.
· Deficiency causes burning feet syndrome.
· Deficiency causes burning feet syndrome.
Source: Kidney, Liver, Milk and Yeast.
e. Vitamin B6
· Daily requirement 2 mg
·Also known as Pyridoxine.
· Daily requirement 2 mg
·Also known as Pyridoxine.
· B6 is the name given by Gyorgy.
· Deficiency causes Anaemia, Nervousness, Irritability, Mental disorder and morning disease.
· Deficiency causes Anaemia, Nervousness, Irritability, Mental disorder and morning disease.
f. Vitamin B7
· Daily requirement trace
· Also known as Biotin or Vit. H.
· Deficiency causes muscular pain.
Source: Vegetable, yeast, wheat and egg.
· Daily requirement trace
· Also known as Biotin or Vit. H.
· Deficiency causes muscular pain.
Source: Vegetable, yeast, wheat and egg.
g. Vitamin B12
· Daily requirement trace
· Also known as Cyanocobalmin.
· It is an anti-pernicious anaemic vitamin.
· It is required or needed for the formation of RBC.
· Deficiency causes pernicious anaemia in which haemoglobin content is less and number of RBC’s are less and RBC’s are not matured.
· Deficiency causes pernicious anaemia in which haemoglobin content is less and number of RBC’s are less and RBC’s are not matured.
· It has Co (cobalt)
Source: Liver, Fish, Meat, Egg, Milk.
Source: Liver, Fish, Meat, Egg, Milk.
h. Folic Acid B9
· Daily requirement 0.5 mg
· Also known as Folacin.
· Daily requirement 0.5 mg
· Also known as Folacin.
· Folic acid name was given by Williams Mitchell.
· Deficiency causes anaemia.
· Deficiency causes anaemia.
· It is needed for the formation of RBC.
Source: Liver, Kidney, Soyabean & Yeast.
Source: Liver, Kidney, Soyabean & Yeast.
C. Vitamin C
· Daily requirement 50 mg
· Ascorbic acid, Antiviral vitamin, Anticancer vitamin, Anti rabies vitamin, Anti scurvy vitamin.
· Daily requirement 50 mg
· Ascorbic acid, Antiviral vitamin, Anticancer vitamin, Anti rabies vitamin, Anti scurvy vitamin.
· It is the earliest known vitamin.
· It was isolated by Szent Gyorgy.
· It is a vitamin that is destroyed in cooking.
· It is excreted in the urine.
· It is essential for the formation of collagen fibres, cartilage, bone, teeth, connective tissue and RBC.
Sources: Amala, Tomato, Orange.
· Deficiency causes scurvy.
D. Vitamin B15
· Pangamic Acid
· It is used for the formation of Antivenom.
· It is used for the formation of Antivenom.
E. Vitamin B17
· Amygdalin
· Amygdalin
· It is recent Anticancer vitamin.
· Vitamins for heartbeat = C
· Vitamins for tears = A (A2)
· Vitamins for tears = A (A2)
TERPENES
· Lipids constructed from the five-carbon compound isoprene are called terpenes.· Chemically, it is made up of a porphyrin head without a phytol tail.
· Isoprene and its derivatives are joined in various combinations to produce substances such as Vitamin A, Coenzyme Q and carotenoids.
· Menthol and camphor are the common terpenes
NUCLEIC ACIDS
· Most essential molecule of life which form the genetic material of all organisms including viruses.· Nucleic acids are the polymer of nucleotides.
· Each nucleotide consists of
(a) Pentose sugar (ribose or deoxyribose sugar),
(b) Nitrogen base (purine or pyrimidine),
(c) Phosphoric acid.
Two types of pentose sugar – Ribose sugar in RNA and Deoxyribose sugar in DNA.
· Nitrogen bases may be purine or pyrimidine.
· Purines – Adenine (A) and Guanine (G)
· Pyrimidines – Cytosine (C), Thymine (T) and Uracil (U)
· Uracil is present in RNA only in place of thymine.
· Two nucleotides are joined together by a Phosphodiester bond.
· Nucleoside – formed by the combination of sugar and a base. E.g. Ribonucleosides & Deoxyribonucleosides.
· Nucleotide = Nucleoside + Phosphate group
· Complementary bases are
· Adenine & Thymine (A = T) by two hydrogen bonds.
· Cytosine & Guanine (C ≋ G) by three hydrogen bonds.
· Other nucleotides are AMP, ADP, ATP, NAD, NADP, FMN, FAD.
· Nucleic acids are broadly divided into
1. Ribonucleic acid (RNA)
2. Deoxyribonucleic acid (DNA)
1. Ribonucleic acid (RNA)
2. Deoxyribonucleic acid (DNA)
A. DNA (Deoxyribonucleic acid)
· Deoxyribonucleic acid or DNA is a molecule that contains the instructions an organism needs to develop, live and reproduce.
· These instructions are found inside every cell and are passed down from parents to their children.
· Deoxyribonucleic acid or DNA is a molecule that contains the instructions an organism needs to develop, live and reproduce.
· These instructions are found inside every cell and are passed down from parents to their children.
DNA structure
· DNA is made up of molecules called nucleotides.
· DNA is made up of molecules called nucleotides.
· Each nucleotide contains a phosphate group, a sugar group and a nitrogen base.
· The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C).
· The order of these bases is what determines DNA's instructions, or genetic code.
· Human DNA has around 3 billion bases, and more than 99% of those bases are the same in all people.
· Similar to the way the order of letters in the alphabet can be used to form a word, the order of nitrogen bases in a DNA sequence forms genes, which in the language of the cell, tells cells how to make proteins.
· There are so many structures of DNA proposed so far, among which Watson and Crick’s right-handed β-model is most widely accepted.
· Another type of nucleic acid, ribonucleic acid, or RNA, translates genetic information from DNA into proteins.
· Nucleotides are attached together to form two long strands that spiral to create a structure called a double helix.
· The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C).
· The order of these bases is what determines DNA's instructions, or genetic code.
· Human DNA has around 3 billion bases, and more than 99% of those bases are the same in all people.
· Similar to the way the order of letters in the alphabet can be used to form a word, the order of nitrogen bases in a DNA sequence forms genes, which in the language of the cell, tells cells how to make proteins.
· There are so many structures of DNA proposed so far, among which Watson and Crick’s right-handed β-model is most widely accepted.
· Another type of nucleic acid, ribonucleic acid, or RNA, translates genetic information from DNA into proteins.
· Nucleotides are attached together to form two long strands that spiral to create a structure called a double helix.
· If you think of the double helix structure as a ladder, the phosphate and sugar molecules would be the sides, while the bases would be the rungs.
· The bases on one strand pair with the bases on another strand: adenine pairs with thymine, and guanine pairs with cytosine.
· DNA molecules are long — so long, in fact, that they can't fit into cells without the right packaging.
· DNA molecules are long — so long, in fact, that they can't fit into cells without the right packaging.
· To fit inside cells, DNA is coiled tightly to form structures we call chromosomes.
· Each chromosome contains a single DNA molecule.
· Humans have 23 pairs of chromosomes, which are found inside the cell's nucleus.
DNA discovery
· DNA was first observed by a German biochemist named Frederich Miescher in 1869.
· DNA was first observed by a German biochemist named Frederich Miescher in 1869.
· But for many years, researchers did not realize the importance of this molecule.
· It was not until 1953 that James Watson, Francis Crick, Maurice Wilkins and Rosalind Franklin figured out the structure of DNA — a double helix — which they realized could carry biological information.
· Watson, Crick and Wilkins were awarded the Nobel Prize in Medicine in 1962 "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material."
· Franklin was not included in the award, although her work was integral to the research.
B. RNA
· It is a single-stranded polymer of nucleotide.
· Its monomer is a ribonucleotide.
· There is no pairing of nitrogen bases.
· In RNA, thymine is replaced by Uracil.
3 types of RNA:
i. mRNA- specifies sequence amino acid in translation.
ii. tRNA- delivers amino acids to the ribosome for protein synthesis.
iii. rRNA- associated with structure and function of the ribosome.
· Ribozyme is the RNA that catalyses the post-transcriptional change in newly formed RNA.
· Structure of t-RNA is cloverleaf model.
· The Segment of DNA which acts as the instructional manual for the synthesis of the protein is a nucleotide.
· Adenosine is an example of Nucleoside.
· It is a single-stranded polymer of nucleotide.
· Its monomer is a ribonucleotide.
· There is no pairing of nitrogen bases.
· In RNA, thymine is replaced by Uracil.
3 types of RNA:
i. mRNA- specifies sequence amino acid in translation.
ii. tRNA- delivers amino acids to the ribosome for protein synthesis.
iii. rRNA- associated with structure and function of the ribosome.
· Ribozyme is the RNA that catalyses the post-transcriptional change in newly formed RNA.
· Structure of t-RNA is cloverleaf model.
· The Segment of DNA which acts as the instructional manual for the synthesis of the protein is a nucleotide.
· Adenosine is an example of Nucleoside.
Functions of Nucleic acid:
i. DNA serves as a repository and transmitter of genetic information in many organisms while RNA is the genetic material of some viruses.
ii. They take part in the central dogma of life.
i. DNA serves as a repository and transmitter of genetic information in many organisms while RNA is the genetic material of some viruses.
ii. They take part in the central dogma of life.
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| Fig: The central dogma of life |
iii. DNA controls every aspect of cellular function
iv. Sometimes RNA acts as an enzyme known as RIBOZYME.
v. Chromosome is a coiled and condensed form of DNA along with histone protein.
iv. Sometimes RNA acts as an enzyme known as RIBOZYME.
v. Chromosome is a coiled and condensed form of DNA along with histone protein.
· Ergastic substances or cell inclusions are non-protoplasmic, non-living substances produced due to the activity of protoplasm.
They are
(a) Reserved materials – Carbohydrates, Protein and Lipid.
(b) Secretary materials – Enzymes, Pigments & Nector.
(c) Excretory materials
1. Alkaloids:
· Atropine – obtained from Atropa belladonna, used for making eye drops.
· Caffein
· Colchicine
· Ephedrine
· Morphine – Extracted from the latex of unripe capsule of Papaver somniferum.
2. Latex
3. Gums & Tannins
4. Resin
They are
(a) Reserved materials – Carbohydrates, Protein and Lipid.
(b) Secretary materials – Enzymes, Pigments & Nector.
(c) Excretory materials
1. Alkaloids:
· Atropine – obtained from Atropa belladonna, used for making eye drops.
· Caffein
· Colchicine
· Ephedrine
· Morphine – Extracted from the latex of unripe capsule of Papaver somniferum.
2. Latex
3. Gums & Tannins
4. Resin
Also, Read Notes of other Lessons in Botany: