Elementary composition of body.

1. Carbon - 50%
2. Oxygen -20%
3. Hydrogen -10%
4. Nitrogen - 8%
5. Calcium - 4%
6. Phosphorus - 2%
7. Others - 6%

Chemical composition of body in a 70 KG adult.

1. Water - 60 %
2. Protein -15%
3. Lipid - 15 %
4. Carbohydrate - 2%
5. Minerals - 8 %

Ions and Electrolytes.

• Ions are charged particles; if positively charged, called cation and if negatively charged, called anion.
• Ion may be atom or group of atoms which have lost or gained electron and thus acquired positive
  or negative charge respectively.
• Electrolytes are ionic substances that can conduct the electric current by transfer of ions (not electron), 
• e.g. Na⁺, K⁺, Cl^-, HCO₃^--

Interfacial tension.

• It is the force operating along the surface of separation between two insoluble or sparingly soluble liquids.
• Conceptually it is equivalent to the surface tension.

e.g, In a heterogeneous colloid solution like protein in water, protein represent a phase which is different from that of water because protein is not soluble in water. So a surface of separation will be observed between protein and water exerting interfacial tension between these two phases.

What is surface tension? Characteristics of surface tension?

Definition:
Surface tension is the force acting along the surface of a liquid that keeps the liquid surface in a state of tension and allows the liquid droplets to contract to the smallest possible area with spherical conformation.

Characteristics of surface tension:

• A molecule in the interior of a liquid is completely surrounded by other molecules and so, attracted equally in all directions.
• On a molecule in the surface of liquid however, there is a resultant attraction inwards and because
  of this inward puli, the surface of the liquid always tends to contract to the smallest possible area.
• It is for this reason of inward pull, the drops of liquid become spherical as far as feasible to a minimum surface area.
• As a result of this spontaneous tendency to contract, the surface of liquid behaves as if it were in a state of tension like a stretched elastic membrane.
• To expand the area of the surface of a liquid, it is necessary to bring out the molecules from the bulk of liquid (interior) on to the surface, against the inward pull (surface tension). This can be done by adding surface tension lowering agents into the solution.

What is adsorption? What is the importance of adsorption.

• Adsorption is the phenomenon of adherence where a particular substance is held to the surface of another solid substance. Substance that is adsorbed is called adsorbate and the solid that adsorb is called adsorbing material or adsorbent. (e.g. charcoal, silica gel).

• Adsorption and absorption both are applied to solids, but the former refers to an excess concentration of substance at the surface of solid and the latter implies to penetration of the solid by a given substance.

• The amount of adsorbate adsorbed to an adsorbent depends on
• Total surface area expressed by the adsorbent.
• Nature of adsorbent and adsorbate.

Importance of adsorption:

• Widely used in chromatographic techniques for separation, purification and analysis of various substances, e.g. Adsorption chromatography, Ion exchange chromatography.
• In biological system hydrophilic(water soluble) substances are adsorbed around hydrophobic (water insoluble) substances to keep the hydrophobic substances in solution and to prevent their precipitation.
• Purification of solutions of different substances by removing unwanted substances(adsorbates) with the help of adsorbents.
• e.g. Charcoal as adsorbent can remove dyestuffs and other unwanted substances from solution.

Isoosmotic VS Isotonic Solution

• Solutions having same osmolarity are known as isoosmotic solutions.
• Solutions having same tonicity are known as isotonic solutions.
• Solutions having tonicity like that of plasma are known as isotonic solutions with respect to plasma.
• If two solutions differ with respect to tonicity irrespective of their osrnolarity, water movement (osmosis) will occur from hypotonic to hypertonic solution, but if two solutions are isotonic to each other, then there will be no osmosis between two solutions whatever may be their
  osmolarity status.
• Two solutions, each containing protein 4 mol/L, will generate same osmotic pressure, so they are isoosmotic. They are also isotonic to each other because proteins are nonpermeable solutes and they will not produce transmembrane osmotic gradient by diffusion across the membrane, so there will be no osmosis.
• Two solutions, one with protein 4 mol/L and another with protein 4 mol/L along with urea 4mol/L are not isoosmotic because the osmotic pressure of the pure protein solution will be less than that of the solution containing mixture of protein and urea, but they are isotonic to each
  other because the non-permeable protein concentration in two solutions are equal. Since urea is permeable solute, at equilibrium 4 mol urea will be equalized on either side when the two solutions will be separated by a membrane. So finally both solutions will have same concentration of protein and urea (4 mol/L protein + 2 mol/L urea) causing no osmosis. 
• Two solutions, one with protein 4 mol/L and another with urea 4 mol/L, are iso-osmotic because both will generate same osmotic pressure, but they are not isotonic to each other because non-permeable protein concentration in two solutions are not equal. If the two solutions are
  separated by a semipermeable membrane, permeable urea will be equalized on both sides. Finally at equilibrium the concentration of one solution will be 4 moUL protein + 2 mol/L urea and that of other polution will be 2 mol/L urea. Because of this differential concentration of two
  solutions there will be osmosis from low concentrated solution to high concentrated solution.

 

• Plasma osmolarity is roughly about 290 mOsm/L and here both permeable and non-permeable solutes of plasma contribute. Among the different solutes,NaCl alone contributes about 92% of plasma osmolarity. Since NaCl is a non-permeable solute and it represents almost 100% of plasma osmolarity, so plasma tonicity is also regarded to be 290 mosm/L. Same tonicity (290mOsm/L) also prevails in ICF. Any solution having tonicity less than that of plasma is called hypotonic solution, more than that of plasma is called hypertonic solution and same as that of plasma is called isotonic solution.
• Tonicity of a solution has its effect on cell volume when cells with intracellular tonicity of 290 mosm/L are suspended in that solution. Cell volume increases because of water entry into cells if the solution is hypoionic; cell volume decreases because ofcellular water loss if the solution is hypertonic and cell volume remains normal because of no water movement if the solution is isotonic. 

 

What is osmol? Relation between osmol and mole.

Osmole:

• It is the amount in gram of osmotically active substance which in 1 L solution with water exerts
• Smotic pressure equal to 22.4 almospherc (22.4 x 760 mmHg) and depresses the freezing point
  of water by 1.86 'C.
• Osmotically active substance means any substance which can exert osmotic pressure in solution
  with water.
• For highly osmotically active substances, (e.g. Na*, glucose etc'), relatively small amount of
  them represent 1 osmole compared to osmotically less active substances, (e'g. protein)'
• It is used as the unit of measurement for osmotically active substances'

 

Relation between Osmole and Mole:

What is Mole and What is equivalent? Relation Between them.

Mole

• It is the gram molecular weight of'a substance (if compound) or gram atomic weight of a
  substance (if element).
• Molecular weight or atomic weight of a substance expressed in gram.

Example:

• Atomic weight of calcium = 40; so one mole calcium = 40 I calcium'
• Molecular weight of HrSon = 98; so one mole H2So1= 98 I H2So4'
  Molecular weight of NacI = 58.5; so one mole Nacl = 58,5 g NaCl.
  Molecular weight of HrO = 18; so one mole HrO = 18 g HrO'

Equivalent:

• It is the gram equivalent weight of a substance
• Equivalent weight of a substance expressed in gram

Example:

• Equivalent weight of calcium = 20; so one equivalent calcium = 20 $ calcium'
• Equivalent weight of HrSOn = 49; so one equivalent H,SO, = 49 I H2SO4'

Relation Between Mole and Equivalent:

Solution and different aspect of solution.

Definition:
Solution is a homogeneous mixture of two or more substances (solid, liquid or gases) uniformly distributed among each other.

Homogeneous mixture (homogeneous system)
It is the mixture of two or more substances showing all through same composition.

Heterogeneous mixture (heterogeneous system)
It is the mixture of two or more substances showing different composition in different parts of the total mixture.

Phase:
It is the homogeneous part or parts of a system separated from each other by definite separating surfaces' In homogeneous mixture there is only orru pilur", but in heterogeneous mixture there is more than one phase.
eg: Solid ice floating in water is a system constituted by the mixture of ice and water; here
solid ice represent one phase and water represent another phase.

Solvent:

• Solvent is the component of a solution which forms larger portion of that solution. 
• Physical state of the sorvent must be same as that of solution.

Solute: 

• Solute is the component(s) of a solution which form minor portion of that solution.
• Solutes are held in solution by the solvent.

eg: 0'9% NaCl solution: Here water is solvent because it represents the major portion and its physical state (liquid) is like that (liquid) of solution. Here sodium chloride is solute
because NaCl represent minor portion of solution and it is kept in solution by water.
5%DA (dextrose in aqua): Here dextrose is solute and water is solvent.
 

Heterogeneous solution
It is a heterogeneous mixture of two or more substances constituting a multi phase system having different composition in different parts of the system, e.g. solution of protein in water.
 

Homogeneous solution or true sorution (molecular sorution) 

• It is a homogeneous (singre phase) mixture of sorute and sorvent.
• Solutes exist in the form of molecules/ ions in this solution.
• Here solutes are crystalloid with size less than 1 nm.
• Here solutes do not sediment out even on indefinite standing.
• The difference between solute and solvent molecules with respect to their size is relatively small.
• Solutes cannot be separated from solvent by passing it through filter paper or semipermeable membrane.

What is sugar, Non sugar, Reducing sugar, Non reducing sugar?

Sugar:

• Substances which are water soluble, crystalline and sweet in taste are called sugar. 
• All monosaccharides and disaccharides are sugar.

Non sugar:

• Substances which are water insoluble and amorphous.
• Polysaccharides are non sugar.

Reducing sugar:

• They act as reducing agent in alkaline media.
• Presence of free aldehyde and or ketone functional group is responsible for this property of carbohydrate.
• All monosaccharides maltose and lactose are reducing sugars.
• Reducing property of sugar is tested by their ability to 
• Reduce alkaline CuSO4 solution (Positive Benedict's test)
• From osazone crystal with phenyl hydrazine
• Show maturation

Non reducing sugar:

• They do not contain free aldehyde or ketone as functional group.
• Their functional groups are usually engaged in glycosidic bond formation
• Sucrose is non reducing sugar.

What is carbohydrate? Classify Carbohydrate.

Carbohydrate:
The compound which on hydrolysis produces the substances having aldehyde or ketone functional group.

Classification:
1. Monosaccharide or simple sugar.

• The simplest form of carbohydrate which cannot be hydrolyzed further into further simple form of carbohydrate.
• These are of 3 to 9 carbons and serve as building blocks of all carbohydrate.
• Pentoses and Hexoses are the monosaccharides of greatest biological importance.
• Example: Glucose, Fructose, Galactose, Mannose, Ribose, Ribulose etc.

2. Disaccharide

• Carbohydrate produced by condensation of two monosaccharide units by glycosidic bond.
• Sugars that produce two molecules of same or different monosaccharide on hydrolysis.
• Example: Maltose (Consists of two glucose molecules)

                        Lactose (Consists of one glucose and one galactose)
                       Sucrose (Consists of one glucose and one Fructose)
3. Oligosaccharide

• Carbohydrate produced by condensation of 3 to 10 monosaccharide units by glycosidic bond.
• Example: Maltotriose, Raffinose, Blood group substances.

4. Polysaccharide:

• Polymer of monosaccharide composed of more than 10 monosaccharide units connected by glycosidic bond.
• Example: Starch, Glycogen, Cellulose, Mucopolysaccharide, Glycoprotein.