MD

         example of biotic resources: Living organisms and their products

1. The resources have no change of getting depleted or exhausted
2. The resources are present in unlimited or infinite quantities
3. Excessive and improper use may result in their pollution .
4. Example of Inexhaustible resources: Solar energy, (cosmic resources) wind power, hydro power, rain fall (climatic resources)

b) Exhaustible (Depletable):

1. The resources have every chance of getting depleted or exhausted. 
2. The resources have finite supply
3. Excessive and improper use may result in wastage and depletion of the resources.
4. Example of Exhaustible resources: Forests, grassland, fossil fuels, minerals,

Energy is defined as the capacity of a substance or a body to do work. Conventional sources of energy refer to the energy sources that have been traditionally used for many years. These energy sources are non-renewable and likely to be depleted due to its extensive use. Non-conventional energy sources are alternate energy resources to the conventional energy resources but in limited use due to lack of feasible technology.
Conventional vs Non conventional Sources of Energy 

Conventional Energy Resources	Non-conventional  Energy Resources
It refers to the traditional sources of power or energy like firewood, coal, petroleum etc	It refers to recently developed sources of energy from sun, wind, tides etc
Energy sources are non-renewable	Energy sources are renewable
Comparatively expensive to maintain, store and transport	Initial expenditure for energy generation is high but cheaper in the long run
Following established technologies for energy production	Require new feasible technologies; still under research and development
Energy sources which are fixed in nature	Generally energy sources are not be fixed in nature
Available in limited quantity; exhaustible	Available in plenty; inexhaustible
Causes large scale pollution; not eco-friendly	Generally Eco-friendly source of energy
Causes green house effect and major culprit in climate change and has serious health consequences	No such issues as energy source is ecologically safe
At present, widely used energy source	Presently limited use; feasible technologies are yet to be developed
Examples: coal, petrol, diesel, LPG etc	Examples: solar energy, wind energy, hydroelectric power etc

Blood is a fluid connective tissue. It is an extremely complex substance carrying a wide variety of cells and substances to all areas of he body. Blood is often described as seat of the soul since it performs several vital functions of the body . A normal  healthy man has about 5.5 litres of blood.

•      Regulate body temperature. 
•      Maintains a constant pH and water balance 
•      Defence against pH and water balance 
•      Transport digested food materials, respiratory gases and waste materials

• Transport: Plasma transport the digested food products like glucose, amino acids, fatty acids, etc.
• Body immunity: one type of globulins called immunoglobulins act as antibodies. They inactive invading microorganisms and their toxins.
• Prevention of blood loss:  Fibrinogen helps in blood clotting and thus prevents blood loss. During blood clotting the soluble fibrinogen is converted into insoluble fibrin.
• Retention of fluid in blood
• Maintenance of blood pH: Plasma proteins act as acid base buffers and thus maintain the blood pH by neutralizing strong acids and bases.
• Regulation of body temperature: Plasma helps in the uniform distribution of heat all over the body, and in conducting heat to skin for dissipation.

 Gram staining  is a special technique which is used to stain bacteria. This technique was developed by Christian Gram in 1884. The stain  stain used in Gram staining is called Gram stain. Chemically Gram stain is a weakly alkaline solution of crystal violet or gentian violet.

On the basis of cell wall structure and its staining ability with Gram stain, bacteria are grouped into two categories. They are Gram positive bacteria and Gram negative bacteria

Cell wall of Gram positive bacteria	Cell wall of Gram negative bacteria
Cell wall is single layered and primarily made up of peptidoglycan	Cell wall is double layered and with an outer membrane outside to Peptidoglycan layer
Gram positive cell wall retain the primary stain of Gram staining (crystal violet) and appear purple after alcohol treatment	Gram positive cell wall lose the primary stain of Gram staining (crystal violet) after alcohol treatment; and appear pink with counter stain (safranin)
Thick peptidoglycan layer of about 20 to 80 nm	Peptidoglycan layer thin and single layered (about 5 to 10 nm thick)
Periplasmic space is absent	Periplasmic space* is absent
Outer membrane is absent	Outer membrane is present outside to Peptidoglycan layer (about 7.5 to 10 nm thick)
Teichoic acid is present	Generally Teichoic acid is absent
Generally **Porins are absent	Porins are present
Very low lipid content (2-5%)	Very high lipid content (15-20%)
Generally Lipopolysaccharide (LPS) is absent**	Lipopolysaccharide (LPS) is present
Lysozyme degrade peptidoglycan wall cause lysis of cell (sensitive to lysozyme)	Lysozyme cannot degrade Gram negative bacteria as Peptidoglycan is protected by outer membrane (resistant to lysozyme)
Example of Gram Positive Bacteria	Example of Gram Negative Bacteria

Fatty acids are organic acids having hydrocarbon chains that end in a carboxylic groups (COOH). Hydrocarbon chains may be straight or having ring structure. Some fatty acids also possess hydroxyl groups. Length 4-24 carbons. Fatty acids are of two main groups: saturated and unsaturated. Saturated fatty acids do not posses double bonds in their carbon chains. They have a general formula C_nH_2nO_2.

Saturated fats	Unsaturated fats
They do not possess any double bonds in their fatty acids.	They contain one or more double bonds in their fatty acids.
All certain atoms are fully saturated	Carbon atoms are unsaturated in the region of double bonds.
They have straight chains.	The chain bends at the double bond.
They have higher melting point	They have lower melting point
Hydrogenation has no effect on saturated fats	Hydrogenation converts unsaturated fats into saturated ones.
Saturated fats are solids at room temperature.	Unsaturated fats are liquid at room temperature.
Animal fats are mostly saturated fats	Plant fats are generally unsaturated fats.
They increase blood cholesterol	Unsaturated fats lower blood cholesterol.
Essential fatty acids are absent.	Essential fatty acids are present.
They are not much affected by exposure to air	On exposure to air, they tend to solidify
Example of Saturated fats: C16H3202 (Palmitic acid) C18H36O2(Stearic acid).	Example of unsaturated fats: Oleic acid (with one double bond, monoene) Linoleic acid  (with one double bond, diene) Linolenic acid  (with one double bond, triene) Arachidonic acid (with one double bond, tetraene)

Aqueous humour	Vitreous humour
It occurs in aqueous chamber	It occurs in vitreous chamber
It is a watery fluid	It is a jelly like substance
It is secreted by ciliary processes	It is apparently  secreted by retina during development of eye.
It is continuously absorbed into blood and replaced.	It is absorbed or replaced.
It contains most of the diffusible substances of the plasma	It consists of water (90%), protein vitrein, hyaluronic acid and collagen fibres.
Obstruction in its flow may damage retina by increasing intraocular pressure	It does not flow.
Maintains the shape of the cornea and supply nutrition to both lens and cornea.	Maintains the shape of the eye ball and contribute to intraocular pressure and also to the focussing of light on the retina.