ACIDS AND BASES

SOME IMPORTANT FACTS ABOUT BIOLOGY

**In the year 1817, Johann Wolfgang Döbereiner, a German chemist, tried to arrange the elements with similar properties into groups. He identified some groups having three elements each. So he called these groups ‘triads’.

**In 1866, John Newlands, an English scientist, arranged the then known elements in the order of increasing atomic masses. He started with the element having the lowest atomic mass (hydrogen) and ended at thorium which was the 56^th element. He found that every eighth element had properties similar to that of the first. He compared this to the octaves found in music. Therefore, he called it the ‘Law of Octaves’.

**The main credit for classifying elements goes to Dmitri Ivanovich Mendeléev, a Russian chemist.

**On this basis, Mendeléev formulated a Periodic Law, which states that ‘the properties of elements are the periodic function of their atomic masses’.

**In 1913, Henry Moseley showed that the atomic number of an element is a more fundamental property than its atomic mass as described below.:: ‘Properties of elements are a periodic function of their atomic number.’

**Atomic radius decreases in moving from left to right along a period. This is due to an increase in nuclear charge which tends to pull the electrons closer to the nucleus and reduces the size of the atom.

**Metals like Na and Mg are towards the left-hand side of the Periodic Table while the non-metals like sulphur and chlorine are found on the right-hand side.

**Oxides of metals are basic and that of non-metals are acidic in general.

**Mendel used a number of contrasting visible characters of garden peas – round/wrinkled seeds, tall/short plants, white/violet flowers and so on.

**Most human chromosomes have a maternal and a paternal copy, and we have 22 such pairs. But one pair, called the sex chromosomes, is odd in not always being a perfect pair. Women have a perfect pair of sex chromosomes, both called X. But men have a mismatched pair in which one is a normal-sized X while the other is a short one called Y. So women are XX, while men are XY.

**A child who inherits an X chromosome from her father will be a girl, and one who inherits a Y chromosome from him will be a boy.

**The basic structure of the limbs is similar though it has been modified to perform different functions in various vertebrates. Such a homologous characteristic helps to identify an evolutionary relationship between apparently different species. The designs of the two wings(bats/birds), their structure and components, are thus very different. They look similar because they have a common use for flying, but their origins are not common. This makes them analogous characteristics, rather than homologous characteristics.

**Alkaline potassium permanganate or acidified potassium dichromate are oxidising alcohols to acids, that is, adding oxygen to the starting material. Hence they are known as oxidising agents.

**Unsaturated hydrocarbons add hydrogen in the presence of catalysts such as palladium or nickel to give saturated hydrocarbons. Catalysts are substances that cause a reaction to occur or proceed at a different rate without the reaction itself being affected. This reaction is commonly used in the hydrogenation of vegetable oils using a nickel catalyst. VegeTable oils generally have long unsaturated carbon chains while animal fats have saturated carbon chains. Animal fats generally contain saturated fatty acids which are said to be harmful for health.

**Saturated hydrocarbons are fairly unreactive and are inert in the presence of most reagents. However, in the presence of sunlight, chlorine is added to hydrocarbons in a very fast reaction. Chlorine can replace the hydrogen atoms one by one.

**Ethanol is commonly called alcohol and is the active ingredient of all alcoholic drinks. In addition, because it is a good solvent, it is also used in medicines such as tincture iodine, cough syrups, and many tonics. Ethanol is also soluble in water in all proportions. Consumption of small quantities of dilute ethanol causes drunkenness. However, intake of even a small quantity of pure ethanol (called absolute alcohol) can be lethal.

**Unlike ethanol, intake of methanol in very small quantities can cause death. Methanol is oxidised to methanal in the liver. Methanal reacts rapidly with the components of cells. It causes the protoplasm to get coagulated, in much the same way an egg is coagulated by cooking. Methanol also affects the optic nerve, causing blindness.

**Sugarcane plants are one of the most efficient convertors of sunlight into chemical energy. Sugarcane juice can be used to prepare molasses which is fermented to give alcohol (ethanol). Some countries now use alcohol as an additive in petrol since it is a cleaner fuel which gives rise to only carbon dioxide and water on burning in sufficient air (oxygen).

**The molecules of soap are sodium or potassium salts of long-chain carboxylic acids. The ionic-end of soap dissolves in water while the carbon chain dissolves in oil. The soap molecules, thus form structures called micelles where one end of the molecules is towards the oil droplet while the ionic-end faces outside. This forms an emulsion in water.

**This is caused by the reaction of soap with the calcium and magnesium salts, which cause the hardness of water. This problem is overcome by using another class of compounds called detergents as cleansing agents. Detergents are generally ammonium or sulphonate salts of long chain carboxylic acids. The charged ends of these compounds do not form insoluble precipitates with the calcium and magnesium ions in hard water.

THE CRUX OF PHYSICS AND ITS USES

SI unit of Force- Newton(CGS=dyne), 1 newton= 10⁵ dyne.

Si unit of Work- Joule(CGS=erg), 1 joule= 10⁷ erg.

Cream separator, centrifugal drier work on the principle of the Centrifugal force.

SI unit of Power- watt.

Value of g=9.8 m/s² decreases with height or depth from earth’s surface.

Value of g is maximum at poles.

Value of g is minimum at equator.

Value of g deceases if the angular speed of earth increases and increases if the angular speed of earth decreases.

If the angular speed of earth becomes 17 times its present value, a body on the equator becomes weightless.

Sudden fall in barometric reading is the indication of storm.

Slow fall in barometric reading is the indication of rain.

Slow rise in the barometric reading is the indication of clear weather.

Atmospheric pressure decreases with altitude, this is why it is difficult to cook on the mountain, and the fountain pen of a passenger leaks in aeroplane at height.

Escape velocity for earth= 11.2km/s, for moon= 2.4 km/s.

Pressure at a point in a liquid is proportional to the depth of the point from the free surface.

Pressure at a point in a liquid is proportional to the density of the liquid.

Hydrolic lift,  Hydrolic Press, Hydrolic brake works on the Pascal law.

Archimedes Principle: when a body immersed partly or wholly in liquid, there is an apparent loss in the weight of the body which is equal to the weight of liquid displaced by the body.

Meta Centre: when a floating body is slightly tilted from equilibrium position, the centre of buoyancy shifts. The point at which the vertical lines passing through the new position of center of buoyancy meets with the initial line is known as meta center.

Relative density is measured by Hydrometer.

The density of sea water is more than that of normal water. This explains why it is easier to swim in sea water.

When ice floats in water, its 1/10^th part remain outside the water.

If ice floating in water in a vessel melts, the level of water in the vessel does not change.

Purity of milk is measured by Lactometer.

The height by which liquid ascends or descends in a capillary tube depends upon the radius of the tube.

A piece of blotting paper soaks ink because the pores of the blotting paper serve as capillary tubes.

The oil in the wick of a lamp rises due to capillary action of the threads in the wick.

The root hairs of plants draws water from the soil through the capillary action.

To prevent loss of water due to capillary action, the soil is loosened and split into pieces by the farmers.

If a capillary tube is dipped in water in an artificial satellite, water rises up to the other end of the tube because of its zero apparent weight, how long the tube may be.

Action of towel soaking up water from the body is due to capillary action of cotton in towel.

Melted wax, in a candle rises up to wick by capillary action.

If a clean and dry needle is very slowly kept on the surface of water, it floats due to surface tension.

The addition of detergent or soap decrease the surface tension of water and thus increases the cleaning ability.

Bubbles of soap solution are big because addition of soap decreases the surface tension of water.

When kerosene oil is sprinkled on water, its surface tension decreases. As a result the larva of mosquitoes floating on the surface of water die due to sinking.

Warm soup is tasty because at high temperature its surface tension is low and consequently the soup spreads on all parts of the tongue.

Viscosity is the property of liquids and gases both.

The viscosity of a liquid is due to the cohesive force between the molecules.

The viscosity of a gas is due to the diffusion of its molecules from one layer to another layer.

Viscosity of gases is much less than that of liquids. There is no viscosity in solids.

With rise in temperature, viscosity of liquids decreases and that for solids increases.

Viscosity of a fluid is measured by its coefficient of viscosity. It SI unit is decapoise or pascal second.

Venturimeter, a device used to measure rate of flow of fluid, works on Bernoulli’s theorem.

Speed of sound is maximum in solids and minimum in gases.

Unit of loudness- bel, phon, decibel.

To hear echo, the minimum distance between the observer and the reflector should be 17m.

Persistence of ear (effect of sound on ear) is 1/10sec.

If Mach number>1, body is called supersonic.

If Mach number>5, body is called hypersonic.

Bow waves: when a motor boat in a sea travels faster than sound, then wanes just like shock waves(in air) are produced on the surface of water. These waves are called bow waves.

Electromagnetic waves are transverse, hence the light is transverse wanes.

Wave nature of light explains rectilinear propagation, reflection, refraction, interference, diffraction and polarization of light.

Speed of light was 1^st measured by Roemer.

Light takes 8min 19sec to reach from sun to earth.

The light reflected from moon takes 1.28 second to reach earth.

Concave mirror uses—shaving glass/ reflector for the head lights of a vehicle, search light/ in ophthalmoscope to examine eye, ear, nose/ in solar cookers.

Convex mirror uses—in rear mirror of vehicles since it provides erect images/ in sodium reflector lamp.

 Examples of total internal reflection—sparkling of diamond/ mirage and looming/ shining of air bubble in water/ shining of a smoked ball or a metal ball on which lamp soot is deposited when dipped in water/ in optical fibres.

Myopia or short sightedness—elongation of eye ball along the axis/ shortening of focal length of the eye lens/ over stretching of ciliary muscles beyond the elastic limit. Cure—Diverging lens.

Hypermetropia or long sightedness—shortening of eye ball along the axis/ increase in the focal length of eye lens/ stiffening of the ciliary muscles. Cure—Converging lens.

Presbyopia—this defect is generally found in elderly person. Due to stiffening of ciliary muscles, eye loses much of its accommodating power. As a result distant as well as nearby objects cannot be seen. Cure—Bifocal lens.

Astigmatism—this defect arises due to difference in the radius of curvature of cornea in the different planes. As a result rays from an object in one plane are brought to focus by eye in another plane. Cure—Cylindrical lens.

Kilowatt hour—it is the unit of energy and is equal to the energy consumed in the circuit at the rate of 1 kilowatt (1000 J/s) for 1 hour.

Particle	Mass(Kg)	Charge(Coulomb)	Discoverer
Proton	1.672 x 10-27	1.6 x 10-19	Rutherford(Golastin)
Neutron	1.675 x 10-27	0	Chadwick
Electron	9.108 x 10-31	-1.6 x 10-19	J.J. Thomson
Positron	9.108 x 10-31	1.6 x 10-19	Anderson
Neutrino	0	0	Pauli
Pi-meson	274x9.108 x 10-31	+ve/-ve	Yakawa
Photon	0	0

Radioactivity was discovered by Henry Becquerel, Madame Curie and Pierre Curie for which they jointly won Noble Prize.

Nucleus having protons 83 or more are unstable. They emit alpha, beta and gamma particles and become stable.

Robert Pierre and Madame Curie discovered a new radioactive element—radium.

End product of all radioactive substances after emission is lead.

Radioactivity is detected by Geiger Muller Counter.

Cloud Chamber—is used to detect the presence and kinetic energy of radioactive particles. It was discovered by C.R.T. Wilson.

Fast Breeder Reactor- a nuclear reactor which can produce more missile fuel than it consumes.

THE CRUX OF CHEMISTRY AND ITS USES

Chromatography—name derived from latin word Chroma meaning color. The technique of chromatography is based on the difference in the rates at which the components of mixture are absorbed.

Father of periodic table—Mendeleev.

Acid—sour in taste/ turns blue litmus red/ contains replaceable hydrogen/ gives  hydrogen ion in aqueous solution(Arrhenius theorem)/ can donate a proton(Bronsted & Lowry theorem)/ can accept electron(Lewis theorem).

Citric acid- lemons or oranges/ Lactic acid- sour milk/ Butyric acid- rancid butter/ Tartaric acid- Grapes/ Acetic acid- vinegar/ Maleic acid- apples/ Carbonic acid- soda aerated drinks/ Stearic acid- fats/ Oxalic acid- tomato, wood sorrel.

Hydrochloric acid is used in digestion.

Nitric acid is used in purification of gold and silver.

Conc. H₂SO₄ and HNO₃ is used to wash iron for its galvanization.

Oxalic acid is used to remove rust spot.

Boric acid is a constituent of eye wash.

Formic acid is present in red ants.

Uric acid is present in the urine of animals.

HCL uses- present in gastric juices/ used as a bathroom cleaner/ as a pickling agent before galvanization/ in the tanning of leather/ in the dying and textile industry/ in the manufacture of gelatin from bones.

HNO₃ uses- manufacture of fertilizers like ammonium nitrate/ for explosives like TNT, TNB, Picric acid/ Nitro glycerine(Dynamite)/ found in rain water/ forms nitrates in soil/ in the manufacture of rayon/ in the manufacture of dyes and drugs.

H₂SO₄ uses- in lead acid storage battery/ in manufacture of HCL/ in manufacture of Alum/ in manufacture of fertilizers, drugs, detergents and explosives.

Boric acid uses- as an antiseptic.

Phosphoric acid uses- its calcium salts makes our bones/ it forms phosphatic fertilizers.

Ascorbic acid uses-source of vitamin C.

Acetic/Citric acid uses- flavouring agent and food preservative.

Tartaric acid uses- souring agent for pickles/ a component of baking powder.

Water soluble bases are called alkali ex. NaOH, KOH.

Calcium Chloride—dehydrating agent used for removing moisture from gases.

Zinc phosphide is used for killing rats.

Wood furnitures are coated with zinc chloride to prevent termites.

Excess copper in human beings causes disease called Wilson.

Galvanized iron is coated with zinc.

Rusting of iron is chemical change which increases the weight of iron.

Calcium hydride is called hydrolith.

Calcium hydride is used to prepare fire proof and water proof clothes.

In flash-bulb, magnesium wire is kept in atmosphere of nitrogen gas.

Titanium is called strategic metal because it is lighter than iron.

Group 1^st element are called alkali metals because its hydroxides are alkaline.

Babbitt metal contains 89% Tin(Sn), 9% Antimony(Sb), and 2% Copper(Cu).

Gun powder contains 75% Potassium nitrate, 10% Sulphur and 15% Charcoal.

Chromium trioxide is known as chromic acid.

Nichrome wire is used in electrical heater.

Potassium Carbonate is known as pearl ash.

Generally transition metals and their compounds are coloured.

Zeolite is used to remove hardness of water.

In cytochrome iron is present.

Selenium metal is used in photoelectric cell,

Gallium metal is liquid at room temperature.

Palladium metal is used in aeroplane.

Radium is extracted from pitch blende.

World famous Eiffel tower has steel and cement base.

Actinides are radioactive elements.

Cadmium rod is used in nuclear reactor to slow down the speed of neutron.

Sodium peroxide is used in submarine and also to purify closed air in hospital.

Co(60) is used in cancer.

Onion and garlic odour due to potassium.

Oxides of metals are alkaline.

Silver and copper are the best conductor of electricity.

Gold and silver are the most malleable metals.

Mercury and iron produces more resistance in comparison to the other during the flow of electricity.

Lithium is the lightest and the most reductant element.

In fireworks, the crimson color is due to presence of strontium.

Green color in fireworks is due to the presence of barium.

Barium Sulphate is used in x-ray of abdomen as Barium metal.

Osmium is the heaviest metal and Platinum is the hardest.

Zinc oxide is known as the flower of zinc. It is also known as the Chinese white and is used as white paint.

Silver chloride is used in photochromatic glass.

Silver Iodide is used in artificial rain.

Silver nitrate is used as a marker during election. It is kept in colored bottle to avoid decomposition.

Silver spoon is not used in egg food because it forms black silver sulphide.

To harden gold, copper is added to it. Pure gold is 24 carat.

Iron pyrites is known as fools’ gold.

Mercury is kept in iron pot because it doesn’t form amalgam with iron.

In tubelight there is a vapour of mercury and argon.

Tetra-ethyl lead is used as anti-knocking compound.

Lead pipe is not used for drinking water because it forms poisonous lead hydroxide.

Fuse wire is made up of lead and tin.

Diamond has maximum refractive index and due to total internal reflection, it has lustre.

Choloform in sunlight forms poisonous has Phosgene(COCL₂).

To decrease the basicity of soil gypsum is added.

In the preparation of talcum powder theo phestal mineral is used.

Potassium chloride is most suitable for removal of permanent hardness of water.

To avoid melting of ice gelatin is used.

When dry ice is heated it directly converts to gas.

Saccharine is prepared from toluene.

Cream is a type of milk in which the amount of fat is increased while the amount of water is decreased.

Bones contains about 58% calcium phosphate.

Phosphine gas is used in voyage as Holmes Signal.

Chlorine gas bleaches the color of flower.

Red phosphorous is used in match industry.

Urea contains 46% nitrogen.

In the electroplating of vessel NH₄Cl is used.

Power alcohol is prepared from mixing pure alcohol in benzene which is used as rocket fuel.

Artificial perfumes are prepared from Ethyl acetate.

Urea was the 1^st organic compound synthesized in laboratory.

Vinegar contains 10% acetic acid.

Acetylene is used for light production.

Ferric chloride is used to stop bleeding.

Cesium is used in solar cells.

Yellow phosphorous is kept in water.

Sea weeds contains iodine.

For artificial respiration a mixture of oxygen and helium gas is used in cylinders.

In cold places, to decrease the freezing point ethylene glycol is used.

Hydrogen peroxide is used for oil paintings.

Heaviest element is Osmium.

Sodium is kept in Kerosene oil.

Radon is the heaviest gas.

Sulphuric acid is known as the oil of vitriol.

Polonium has the maximum number of isotopes.

Flourine is the most oxidizing agent.

BIOLOGY AND THEIR STUDIES

Biology was first coined by Lamarck and Treviranus in the year 1801.

Agrology- soil science especially dealing with the production of crops.

Agrostology- study of grass.

Arthrology- study of joints.

Anthology- study of flower and flowering plants.

Andrology- study of male reproductive organs.

Bryology- study of Bryophytes.

Cytology- study of cells.

Cryobiology- study of effect of low temperature on organisms.

Cardiology- study of heart.

Dendrochronology- counting and analysing annual growth rings of tree to know its age.

Embryology- study of fertilization of egg, formation of zygote and development of embryo.

Eugenics- study of factors connected with the improvement of human race.

Ethnology- study of science dealing with different races of human.

Ethology- study of animal behavior in their natured habitats.

Etiology- study of causative agent of disease.

Entomology- study of insects.

Exobiology- study of possibility of life in space.

Floriculture- cultivation of plant for flower.

Fermentation- process of incomplete oxidation that occur in microbes and other cells in absence of oxygen, leading to the formation of ethyl alcohol.

Gynecology- study of female reproductive organs.

Gastroenterology- study of alimentary canal or stomach, intestine and their disease.

Histology- study of tissues via microscope.

Hydroponics- study of growing plant without soil in water which contains the nutrients.

Hematology- study of blood.

Hepatology- study of liver.

Ichthyology- study of fishes.

Kalology- study of human beauty.

Metazoans- all multicellular animals are called metazoans.

Monoecious- plant which have both male and female flower.

Morphology- study of external structure.

Mycology- study of fungi.

Neurology- study of nervous system.

Neonatology- study of new born.

Nephrology- study of kidneys.

Odontology- study of teeth and gums.

Osteology- study of bones.

Ornithology- study of birds.

Ophthalmology- study of eyes.

Sphygmology- study of pulse and arterial pressure.

Saurology- study of lizards.

Rhinology- study of nose and olfactory organs.

Cell word was coined by the British scientist Robert Hooke in the year 1665.

The smallest cell is Mycoplasma gallisepticum.

The longest cell is neuron.

The biggest cell is the Ostrich egg.

Schilden and Schwann established the cell theory.

Cell wall- plant cell there is a rigid cell wall which is non-living and freely permeable, made of cellulose and chitin.

Cell membrane- it forms the outer cover of the animal cells. In plant cells it is present in the inner layer to the cell wall. Made up of phospholipids.

Protoplasm- fluid present in the cell membrane, discovered by Purkenje, contains ions, salts etc. (Cytoplasm- fluid found outer the nuclear membrane/ Nucleoplasm- fluid found inside the nucleus).

Mitochondria- discovered by Altman, fluid present inside is called matrix, it synthesizes energy rich compound ATP.

Golgi Bodies- discovered by Camilo Golgi, made up of a group of tubes/vesicles/vacuoles.

Endoplasmic Reticulum- membranous network of tubules like structure found in the cytoplasm is called endoplasmic reticulum, helps in distribution of materials, forms the supporting framework of cell.

Ribosome- discovered by Palade, small granules like structure found attached to the endoplasmic reticulum, made up of RNA.

Lysosome- discovered by De Duve, sac like structure bounded by single membrane and contains hydrolytic enzyme, known as suicidal bags.

Centrosome- discovered by Boveri, found only in animal cell taking part in cell division.

Plastid- (Chloroplast-contains chlorophyll, known as the kitchen of the cell, granum is the site of light reaction during photosynthesis while stroma is the site of dark reaction), (Chromoplast-provides various colors to plants), (Leucoplast- colorless, stores food in form of starch/fat/protein).

Vacoule- fluid filled single membrane bounded, dead organelles of cell. In Plant cell it is larger than animal cells.

Deoxyribonucleic acid- Frederic Meischer was the 1^st who isolated DNA from nucleus. Contains(nitrogen base-purine-adinine, guanine/nitrogen base-pyrimidines-thymine, cytosine), Watson and crick give the structural model of DNA of double helical strand containing polynucleotide strand, contains deoxyribose sugar.

Ribonucleic acid- single stranded nucleic acid made up of phosphate, ribose sugar and nitrogen base uracil, adinine, guarine and cytosine. (mRNA- brings the message from DNA found in the nucleus to cytoplasm in coded form/rRNA- present in ribosome which is the site of protein synthesis/tRNA- it is the carrier of amino acid and transfer it to the ribosome).

Johann Mendel is known as the father of genetics.

Klinefelter Syndrome- when a male have an extra X or Y chromosome in sex chromosome then the condition will be XXY or XYY instead of XY. The individual with this syndrome have masculine development but feminine development is not completely suppressed and the individual becomes sterile. In females they show normal development but limited fertility.

Turner’s Syndrome- when female has single sec chromose(X0) their ovaries are rudimentary and lack secondary sexual characters.

Down’s Syndrome- when an extra chromosome is added to the 21^st autosomal chromosome.

Homologous organs- organ which are seen different sue to use in various functions but its structure and embryonic development are similar ex. Flipper of whale, feather of bat, paw of cat.

Analogous organ- organ which looks similar due to be used in similar functions but their internal structure and embryonic development are different. Ex. Feather of butterfly, bats, birds.

Useful Algae: (as food- Porphyra, Ulva, Surgassum, Laeminaria, Nostoc)/ (in making iodine- Laeminaria, Fucus, Echlonia)/ (as manure- Nostoc, Anabina, Kelp)/ (for medicines- Chloreloline from Chlorella and Tincher iodine made from laminaria)/ (in research- Chlorella Acitabularia, Belonia).

An astronaut can get protein food, water and oxygen by sowing Chlorella Algae in the tank of the aircraft, so chlorella is known as space algae.

Sphagnum moss is used to soak water/ Sphagnum moss is used as fuel/ Sphagnum moss is used as an antiseptic.

Smallest plant is Zaimia Pygmia.

Living fossils are Cycas, Gingko biloba and Metasequoia.

Gingko biloba is also called Maiden Hair Tree.

Ovules and Antherzoids of Cycas is the largest in the Plant Kingdom.

Viruses in which RNA substance is found as genetic material are called Retrovirus.

Bacteria was discovered by Anton Von Leuwenhoek.

Some species of Azotobacter, Azospirillum and Clostridium bacteria live freely in the soil and fix atmospheric nitrogen into nitrogenous compound. Anabaena and Nostoc cynobacteria fix atmospheric bacteria into soil.

The species of Rhizobium and Bradyrhizobium etc. bacteria live in the roots of the leguminous plants capable of converting atmospheric nitrogen into its compound.

Rate of photosynthesis is maximum in red light and minimum in violet light.

Four pairs of heart in earthworm.

Six feet and four wings in insects.

Cockroaches’ heart have 13 chambers.

 Cobra is the only snake that makes nests.

Heloderma is the only poisonous lizard.

Sea Snake which is called Hydrophis is the world’s most poisonous snake.

Largest zoo in India- Alipur(Kolkata)/ Largest zoo in world- Cruiser National Park(South Africa).

In mammals the highest body temperature is of goat.

Echidna and Duck billed Platypus are egg laying animals.

Serum- when Fibrinogen & protein is extracted out of plasma, the remaining plasma is serum.

RBC contains no nucleus (except-camel & Ilama).

RNC is formed in bone marrow (in embryonic stage it is formed in liver).

Liver (Spleen) is called the grave of RBC.

Iron compound found in hemoglobin is haematin.

The main reason behind the difference in the human blood is the glyco protein which is found in Red Blood Corpuscles called antigen.

No.	Blood Group	Antigen(in RBCs)	Antibody(in plasma)
1.	A	Only A	Only b
2	B	Only B	Only a
3.	AB	Both A & B	Absent
4.	O	Absent	Both a and b

Sino-auricular node- It is specialized area of cardiac muscle fiber in right auricle. SA node is also known as pace maker as it generates each wave of cardiac impulse.

Thyroxine and Adrenaline are hormones which independently controls the heart beat.

639 muscles in human body.

Largest muscle of the body is Gluteus Maximus.

Smallest muscle of the body is Stapedius.

Facts	Example & details
Largest angiosperm tree	Eucalyptus
Longest tree in world	Sequoia Giganteum. This is a gymnosperm. It’s height is 120m. Also called Red Wood of California.
Smallest Angiosperm Plant	Lemna.
Plant with largest leaf	Victoria Regia
Largest fruit	Lodoceia
Smallest Pteridophyta	Azolla
Smallest chromosomes	Algae
Longest chromosomes	Trillium
Largest no. of chromosomes in plants	Ophioglossum(Fern)
Least no. of chromosomes in plants	Heplapapopus Gracilis