evolutin.of stages in humans..................

evolution........................

speciation.............

Important terms of heredity and evolution

Heredity: The transmission of characters (traits) from the parents to their off springs is called Heredity.

Variation: The differences in the character among the individuals of a species is called variation is necessity for organic evolution.
Both Heredity & variation are fundamental factors in the process of Evolution of an organism.

Genetics: The branch of biology which studies heredity & variation is called genetic.

Terms gene was coined by scientist – Johanssen in 1909.

Chromosomes: Chromosomes are thread like structures present in the nucleus of a cell which contain hereditary information of the cell. They are made up of DNA & proteins.

Gene: Gene is the unit of inheritance. Various genes are located in the chromosomes at fixed position genes are responsible for our characteristic features.

Chemically gene is a segment of a large polynucleotide molecule called de oxyribonucleic acid
DNA: Dexyribo nucleic acid DNA was first isolated by Frederick meisher from the nucleus of the pus cells.It is acidic in nature so the name is nucleic acid. DNA is a macromolecule/polymer which is made up of a large no. of smaller units called Nucleotide. So DNA is a polynucleotide.

Nucleotide is the basic structure unit of DNA.

Sex Determination: The process by which the sex of a per is determined is called sex determination.
The Chromosomes which determine the sex of a person called sex chromosomes which areof 2 types X & Y.           
                     XX combination is always found in females
                     XY combination is always found in males.

ORGANIC EVOLUTION
Evolution is the sequence of gradual changes which take place in the primitive organisms over millions of yrs. In which non species are provided.

DARWINISM / Theory of Natural Selection (by charles robert darwin)
(a) All the species produce a large no of offsprings but population remains fairly constant due to struggle bt the members of same species & different species for food, space & mate

(b) This struggle eliminates the unfit individuals. (Survival of the fittest)

(c) This gives orgin to variations which pass into progeny & over a long period of time, leads to origin of new species.
Limitations: It could not explain how the variations arise.

evolution .....(introduction)

Evolution is the change in the inherited characteristics of biological populations over successive generations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.


All life on Earth is descended from a last universal ancestor that lived approximately 3.8 billion years ago. Repeated speciation and the divergence of life can be inferred from shared sets of biochemical and morphological traits, or by shared DNA sequences. These homologous traits and sequences are more similar among species that share a more recent common ancestor, and can be used to reconstruct evolutionary histories, using both existing species and the fossil record. Existing patterns of biodiversity have been shaped both by speciation and by extinction.

human eye...............

The human eye is an organ that reacts to light and has several purposes. As a conscious sense organ, the mammalian eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth. The human eye can distinguish about 10 million colors.
Similar to the eyes of other mammals, the human eye's non-image-forming photosensitive ganglion cells in the retina receive light signals which affect adjustment of the size of the pupil, regulation and suppression of the hormone melatonin and entrainment of the body clock.

 1. vitreous body 2. ora serrata 3. ciliary muscle 4. ciliary zonules 5. Schlemm's canal 6. pupil 7. anterior chamber 8. cornea 9. iris 10. lens cortex 11. lens nucleus 12. ciliary process 13. conjunctiva 14. inferior oblique muscle 15. inferior rectus muscle 16. medial rectus muscle 17. retinal arteries and veins 18. optic disc 19. dura mater 20. central retinal artery 21. central retinal vein 22. optic nerve 23. vorticose vein 24. bulbar sheath 25. macula 26. fovea 27. sclera 28. choroid 29. superior rectus muscle 30. retina

General properties

The eye is not shaped like a perfect sphere, rather it is a fused two-piece unit. The smaller frontal unit, more curved, called the cornea is linked to the larger unit called the sclera. The corneal segment is typically about 8 mm (0.3 in) in radius. The sclerotic chamber constitutes the remaining five-sixths; its radius is typically about 12 mm. The cornea and sclera are connected by a ring called the limbus.

Human Iris, Blue type

The iris – the color of the eye – and its black center, the pupil, are seen instead of the cornea due to the cornea's transparency. To see inside the eye, an ophthalmoscope is needed, since light is not reflected out. The fundus (area opposite the pupil) shows the characteristic pale optic disk (papilla), where vessels entering the eye pass across and optic nerve fibers depart the globe.

Components

The eye is made up of three coats, enclosing three transparent structures. The outermost layer, known as the fibrous tunic, is composed of the cornea and sclera. The middle layer, known as the vascular tunic or uvea, consists of the choroid, ciliary body, and iris. The innermost is the retina, which gets its circulation from the vessels of the choroid as well as the retinal vessels, which can be seen in an ophthalmoscope.

Blood vessels can be seen within the sclera, as well as a strong limbal ring around the iris.

Within these coats are the aqueous humour, the vitreous body, and the flexible lens. The aqueous humour is a clear fluid that is contained in two areas: the anterior chamber between the cornea and the iris, and the posterior chamber between the iris and the lens. The lens is suspended to the ciliary body by the suspensory ligament (Zonule of Zinn), made up of fine transparent fibers. The vitreous body is a clear jelly that is much larger than the aqueous humour present behind the lens, and the rest is bordered by the sclera, zonule, and lens. They are connected via the pupil.

Pupil constriction

Lenses cannot refract light rays at their edges as well as they can closer to the center. The image produced by any lens is therefore somewhat blurry around the edges (spherical aberration). It can be minimized by screening out peripheral light rays and looking only at the better-focused center. In the eye, the pupil serves this purpose by constricting while the eye is focused on nearby objects. In this way the pupil has a dual purpose: to adjust the eye to variations in brightness and to reduce spherical aberration.

Effects of aging

There are many diseases, disorders, and age-related changes that may affect the eyes and surrounding structures.
As the eye ages, certain changes occur that can be attributed solely to the aging process. Most of these anatomic and physiologic processes follow a gradual decline. With aging, the quality of vision worsens due to reasons independent of diseases of the aging eye. While there are many changes of significance in the non-diseased eye, the most functionally important changes seem to be a reduction in pupil size and the loss of accommodation or focusing capability (presbyopia). The area of the pupil governs the amount of light that can reach the retina. The extent to which the pupil dilates decreases with age, leading to a substantial decrease in light received at the retina. In comparison to younger people, it is as though older persons are constantly wearing medium-density sunglasses. Therefore, for any detailed visually guided tasks on which performance varies with illumination, older persons require extra lighting. Certain ocular diseases can come from sexually transmitted diseases such as herpes and genital warts.

SOAPS AND DETERGENTS

Soaps are sodium salts of long chain carboxylic acids. The soapiness in soap comes from the sodium salts of fatty acids like stearic acid, oleic acid andpalmitic acid.
Sodium Oleate  Sodium Palmitate  

The ionic end of the soap dissolves in water while the carbon chain dissolves in oil. The positively charged heads of the soap molecules repel each other and form a closed structure. This structure is called amicelle. The dirt is pulled and absorbed into the centre of the micelle. This property of soap makes it anemulsifier.

Sometimes, soaps don’t lather well with hard water. Hard water contains calcium and magnesium, which combine with soap molecules to form insoluble precipitates.

Detergents consist of long chain molecules such as sodium n-dodecyl benzene sulphonate and sodium n- dodecyl sulphate. The charged ends of these compounds do not form insoluble precipitates with the calcium and magnesium ions in water.  Detergents are

used in shampoos and products for cleaning clothes.

             

structure of sodium n-dodecyl benzene sulphonate,

structure of sodium n-dodecyl sulphate

SOURCE: www.learnnext.com

reproduction in human beings..........................

 sexual reproduction in human beings

Sexual intercourse (or coitus or copulation) is, broadly, the insertion and thrusting of a male's penis, usually when erect, into a female's vagina for the purposes of sexual pleasure or reproduction; also known as vaginal intercourse or vaginal sex. Other forms of penetrative sexual intercourse include penetration of the anus by the penis (anal sex), penetration of the mouth by the penis or oral penetration of the vulva or vagina (oral sex), sexual penetration by the fingers (fingering), and sexual penetration by use of a strap-on dildo. These activities involve physical intimacy between two or more individuals and are usually used among humans solely for physical or emotional pleasure and commonly contribute to human bonding.A variety of views concern what constitutes sexual intercourse or other sexual activity and their effects on health. While the term sexual intercourse, particularly the variant coitus, most commonly denotes penile-vaginal penetration and the possibility of creating offspring (the fertilization process known as reproduction), oral sex (especially when penetrative) and particularly penile-anal sex are also commonly considered sexual intercourse. Non-penetrative sex acts (such as non-penetrative forms of cunnilingus or mutual masturbation) have been termed outercourse, but may additionally be among the sexual acts contributing to human bonding and considered sexual intercourse The term sex, often a shorthand for sexual intercourse, can mean any form of sexual activity. Because people can be at risk of contracting sexually transmitted infections during these activities, though the transmission risk is significantly reduced during non-penetrative sex,safe sex practices are advised.

Health effects

Benefits

In humans, sexual intercourse and sexual activity in general have been reported to produce health benefits as varied as improved sense of smell, stress and blood pressure reduction,increased immunity, and decreased risk of prostate cancer. Sexual intimacy, as well as orgasms, increases levels of the hormone oxytocin, also known as "the love hormone", which helps people bond and build trust. Sexual intercourse and sexual activity in general are aspects of many mood repair strategies, which mean they can be used to help dissipate feelings of sadness or depression.

Risks

Sexually transmitted infections (STIs) can be spread by person-to-person sexual contact, especially penetrative sexual intercourse. There are 19 million new cases of sexually transmitted infections every year in the U.S., and, in 2005, the World Health Organization estimated that 448 million people aged 15–49 were being infected a year with curable STIs (such as syphilis, gonorrhea and chlamydia).
STIs are caused by bacteria, viruses and parasites, which are passed from person to person during sexual contact. Some, in particular HIV and syphilis, can also be passed in other ways, including from mother to child during pregnancy and childbirth, through blood products, and by shared hypodermic needles. Gonococcal or chlamydial infections often produce no symptoms. Untreated chlamydial infection can lead to female infertility and ectopic pregnancy. Human papillomavirus can lead to genital and cervical cancers. Syphilis can result in stillbirths and neonatal deaths. Untreated gonococcal infections result in miscarriages, preterm births and perinatal deaths. Infants born to mothers with untreated gonorrhoea or chlamydia can develop neonatal conjunctivitis (a serious eye infection), which can lead to blindness. Hepatitis B can also be transmitted through sexual contact. Globally, there are about 350 million chronic carriers of hepatitis B.

Social effects

Adults

Some researchers, such as Alex Comfort, posit three potential advantages of sexual intercourse in humans, which are not mutually exclusive: reproductive, relational, and recreational. While the development of the birth-control pill and other highly effective forms of contraception in the mid- and late 20th century increased people's ability to segregate these three functions, they still overlap a great deal and in complex patterns. For example: A fertile couple may have sexual intercourse while contracepting not only to experience sexual pleasure (recreational), but also as a means of emotional intimacy (relational), thus deepening their bonding, making their relationship more stable and more capable of sustaining children in the future (deferred reproductive). This couple may emphasize different aspects of sexual intercourse on different occasions, being playful during one episode of sexual intercourse (recreational), experiencing deep emotional connection on another occasion (relational), and later, after discontinuing contraception, seeking to achieve pregnancy (reproductive, or more likely reproductive and relational).

Adolescents

With regard to adolescent sexuality, sexual intercourse is usually for relational and recreational purposes as well. However, teenage pregnancy is often disparaged, and research suggests that the earlier onset of puberty for children puts pressure on children and teenagers to act like adults before they are emotionally or cognitively ready,and thus are at risk to suffer from emotional distress as a result of their sexual activities. Some studies have concluded that engaging in sexual activity leaves adolescents, especially girls, with higher levels of stress and depression. A majority of adolescents in the United States have been provided with some information regarding sexuality,though there have been efforts among social conservatives in the United States government to limit sex education in public schools to abstinence-only sex education curricula.

concave and convex lenses

Lenses are the most used things in optical devices like microscopes and telescopes. Bi-convex and bi-concave lenses are the most popular ones in use among school labs. Lenses use the phenomenon of refraction of light to form images.
Concave lens diverge the light incident on it. Hence, called the diverging lens. Due to this these lenses always form diminished, virtual and erect images irrespective of the position of the object in front of them. Thus, the magnification produced by these lenses is always less than one.
Convex lenses converge the light and hence are called the converging lenses. You can observe the magnified image of your palm when the lens is placed close to your palm. This is due the position of the object between the focus and the optic centre. As the object moves away from the lens, the size of its image reduces along with its distance from the lens. Convex lenses form erect, virtual, magnified images or inverted, real, diminished/magnified images depending on the position of the object.
The distance from the principal focus to the optic centre of the lens is the focal length of the lens.
The relation between the focal length (f), object distance (u) and the image distance (v) is given by 1/f = 1/v - 1/u.
All the distances are measured from the optic centre. If we measure the distances in the direction of the incident light, then they are taken positive and else they are taken negative. These constitute the sign conventions.

REFRACTIVE INDEX

In optics the refractive index or index of refraction n of a substance (optical medium) is a dimensionless number that describes how light, or any other radiation, propagates through that medium. It is defined as

,

where c is the speed of light in vacuum and v is the speed of light in the substance. For example, the refractive index of water is 1.33, meaning that light travels 1.33 times slower in water than it does in vacuum. (See typical values for different materials here.)
The historically first occurrence of the refractive index was in Snell's law of refraction, n₁sinθ₁= n₂sinθ₂, where θ₁ and θ₂ are the angles of incidence of a ray crossing the interface between two media with refractive indices n₁ and n₂.
Refraction, critical angle and reflection of light at the interface between two media.
Brewster's angle, the critical angle for total internal reflection, and the reflectivity of a surface also depend on the refractive index, as described by the Fresnel equations.^[1]
The refractive index can be seen as the factor by which the velocity and the wavelength of the radiation are reduced with respect to their vacuum values: the speed of light in a medium is and similarly the wavelength in that medium is , where is the wavelength of that light in vacuum. This implies that vacuum has a refractive index of 1, and that frequency () of the wave is not affected during refraction. Historically other reference media (e.g., air at a standardized pressure and temperature) have been common.
Refractive index of materials varies with the wavelength. This is called dispersion; it causes the splitting of white light in prisms and rainbows, and chromatic aberration in lenses. In opaque media, the refractive index is a complex number: while the real part describes refraction, the imaginary part accounts for absorption.
The concept of refractive index is widely used within the full electromagnetic spectrum, from x-rays to radio waves. It can also be used with wave phenomena other than light (e.g., sound). In this case the speed of sound is used instead of that of light and a reference medium other than vacuum must be chosen.

Refraction of light.............

Refraction

Refraction is the change in direction of a wave due to a change in its transmission medium.

 

Explanation

 

  An object (in this case a pencil) part immersed in water looks bent due to refraction: the light waves from X change direction and so seem to originate at Y. (More accurately, for any angle of view, Y should be vertically above X, and the pencil should appear shorter, not longer as shown.)  

                                             

In optics, refraction is a phenomenon that often occurs when waves travel from a medium with a given refractive index to a medium with another at an oblique angle. At the boundary between the media, the wave's phase velocity is altered, usually causing a change in direction. Its wavelength increases or decreases but its frequency remains constant. For example, a light ray will refract as it enters and leaves glass, assuming there is a change in refractive index. A ray traveling along the normal (perpendicular to the boundary) will change speed, but not direction. Refraction still occurs in this case. Understanding of this concept led to the invention of lenses and the refracting telescope.

 REFRACTIVE INDEX


In optics the refractive index or index of refraction n of a substance (optical medium) is a dimensionless number that describes how light, or any other radiation, propagates through that medium. It is defined as

,

where c is the speed of light in vacuum and v is the speed of light in the substance. For example, the refractive index of water is 1.33, meaning that light travels 1.33 times slower in water than it does in vacuum. (See typical values for different materials here.)
The historically first occurrence of the refractive index was in Snell's law of refraction, n₁sinθ₁= n₂sinθ₂, where θ₁ and θ₂ are the angles of incidence of a ray crossing the interface between two media with refractive indices n₁ and n₂.

Refraction, critical angle and reflection of light at the interface between two media.

NOMECLATURE

Wood Root

This denotes the number of carbon atoms present in a given molecule. For e.g., C₁-Meth, C₂- Eth, C₃ - Prop, C₄- But.

Suffix

The suffix denotes the type of bonds or the functional group present in the carbon chain, e.g.

Type of bond	Functional group
'ane' (single bond)	'ol' for alcohols (-OH)
'ene' (double bond)	'al' for aldehydes (-CHO)
'yne' (triple bond)	'oic acid' for carboxylic acid (-COOH)

Prefix

This denotes the presence of other functional groups and their position.
For e.g., the following compound can be named as:

Word root: But (C₄) Prefix: 3, chloro
Suffix: -ol Name: 3-chloro butanol
Note carbon atoms are numbered from the side of the functional group (-OH in this case).

SIGN CONVENTIONS FOR REFLECTION OF SPHERICAL MIRRORS

MIRRORS	OBJECT DISTANCE (u)	DISTANCE OF REAL IMAGE	DISTANCE OF VIRTUAL IMAGE	FOCAL LENGTH (F)	HEIGHT OF OBJECT	HEIGHT OF REAL IMAGE	HEIGHT OF VIRTUAL IMAGE
CONVEX	NEGATIVE	IMAGE DOES NOT FORM	POSITIVE	POSITIVE	POSITIVE	IMAGE DOES  NOT FORM	POSITIVE
CONCAVE	NEGATIVE	NEGATIVE	POSITIVE	NEGATIVE	POSITIVE	NEGATIVE	POSITIVE

how do organisms reproduce...................

 Asexual reproduction is a mode of reproduction by which offspring arise from a single parent, and inherit the genes of that parent only; it is reproduction which almost always does not involvemeiosis, ploidy reduction, or fertilization. The offspring will be exact genetic copies of the parent, except in the specific case of automixis. A more stringent definition is agamogenesis which is reproduction without the fusion of gametes. Asexual reproduction is the primary form of reproduction for single-celled organisms such as the archaea, bacteria, and protists. Many plants andfungi reproduce asexually as well.



source:   http://www.youtube.com/watch?v=v6osswxstfk

RAY DIAGRAMS OF CONCAVE AND CONVEX MIRRORS

1. AT INFINITY
2.B/W FOCUS AND CENTRE OF CONVATURE
3.AT CENTRE OF CONVATURE
4.B/W CENTER OF CONVATURE AND FOCUS
5.AT INFINITY
6.B/W FOCUS AND POLE

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                                  WE ARE BACK........WITH NEW THINKING,WITH NEW WORKING SPIRIT ETC.....N I HOPE THAT U WILL NOW AGAIN START WORKING WITH THE SAME HOPE AND WILL SCORE MUCH BETTER.....

ALL THE VERY BEST

AS EXAMS ARE APPROACHING....THIS BLOG IS GOING TO BE CLOSED TILL OCTOBER.
SO,ALL THE BEST AND GOOD LUCK.I HOPE OUR HARDWORK AND UR CO-OPERATION WOULD GIVE A POSITIVE OUTPUT.

MEET U ALL AFTER EXAMS ON STARTING OCTOBER........
                                                                                                   DON'T FORGET US .WE WILL MEET U SOON.........

OCEAN THERMAL ENERGY

SOURCE:- YOUTUBE.COM

Tidal energy,

sometimes called tidal power, is the power achieved by capturing the energy contained in moving water in tides and open ocean currents.
There are two types of energy systems that can be used to extracted energy: kinetic energy, the moving water of rivers, tides and open ocean currents; and potential energy from the difference in height (or head) between high and low tides. The first method - generating energy from tidal currents - is becoming more and more popular because people believe that it does not harm the environment as much as barrages or dams. Many coastal sites worldwide are being examined for their suitability to produce tidal (current) energy.

Tidal power is classified as a renewable energy source, because tides are caused by the orbital mechanics of the solar system (ocean currents are caused by the surface effect of winds) and are considered inexhaustible. The root source of the energy is the orbital kinetic energy of the earth-moon system, and also the earth-sun system. Tidal power has great potential for future power and electricity generation because of the essentially inexhaustible amount of energy contained in these rotational systems. Tidal power is reliably predictable (unlike wind power and solar power). In Europe, Tide Mills have been used for nearly 1,000 years, mainly for grinding grains.

Wave Energy

Waves are generated by the wind as it blows across the sea surface. Energy is transferred from the wind to the waves.
Wave energy is sometimes confused with tidal energy, which is quite different.
Waves travel vast distances across oceans at great speed. The longer and stronger the wind blows over the sea surface, the higher, longer, faster and more powerful the sea is. The energy within a wave is proportional to the square of the wave height, so a two-meter high wave has four times the power of a one-meter high wave.

Why Wave Energy?
Wave energy has the potential to be one of the most environmentally benign forms of electricity generation. It is a clean and renewable energy source and its potential is huge. Some additional benefits of wave energy are:

1.  With the wave energy resource distributed across the globe, wave energy offers many countries the benefit of security of supply
2.  Waves are generated over large areas of ocean and, once generated, travel immense distances with only small energy losses.
3.  Waves can be anticipated one or two days in advance through direct satellite measurements and meteorological forecasts which provide a high level of predictability and hence good network planning.

SOURCE:- Wikipedia.org , pelamiswave.com

nuclear energy...................

An absorption or release of nuclear energy occurs in nuclear reactions or radioactive decay; those that absorb energy are called endothermic reactions and those that release energy are exothermic reactions. Energy is consumed or liberated because of differences in the nuclear binding energy between the incoming and outgoing products of the nuclear transmutation.
The best-known classes of exothermic nuclear transmutations are fission and fusion. Nuclear energy may be liberated by atomic fission, when heavy atomic nuclei (like uranium and plutonium) are broken apart into lighter nuclei. The energy from fission is used to generate electric power in hundreds of locations worldwide. Nuclear energy is also released during atomic fusion, when light nuclei like hydrogen are combined to form heavier nuclei such as helium. The Sun and other stars use nuclear fusion to generate thermal energy which is later radiated from the surface, a type of stellar nucleosynthesis. In any exothermic nuclear process, nuclear mass might ultimately be converted to thermal energy, given off as heat, carries away the mass with it.
In order to quantify the energy released or absorbed in any nuclear transmutation, one must know the nuclear binding energies of the nuclear components involved in the transmutation.
 types of nuclear energy.........

Nuclear fusion

The binding energy of helium is the energy source of the Sun and of most stars. The sun is composed of 74 percent hydrogen (measured by mass), an element whose nucleus is a single proton. Energy is released in the sun when 4 protons combine into a helium nucleus, a process in which two of them are also converted to neutrons.
The conversion of protons to neutrons is the result of another nuclear force, known as the weak (nuclear) force. The weak force, like the strong force, has a short range, but is much weaker than the strong force. The weak force tries to make the number of neutrons and protons into the most energetically stable configuration. For nuclei containing less than 40 particles, these numbers are usually about equal. Protons and neutrons are closely related and are sometimes collectively known as nucleons. As the number of particles increases toward a maximum of about 209, the number of neutrons to maintain stability begins to outstrip the number of protons, until the ratio of neutrons to protons is about three to two.
The protons of hydrogen combine to helium only if they have enough velocity to overcome each other's mutual repulsion sufficiently to get within range of the strong nuclear attraction. This means that fusion only occurs within a very hot gas. Hydrogen hot enough for combining to helium requires an enormous pressure to keep it confined, but suitable conditions exist in the central regions of the Sun, where such pressure is provided by the enormous weight of the layers above the core, pressed inwards by the Sun's strong gravity. The process of combining protons to form helium is an example of nuclear fusion.
The earth's oceans contain a large amount of hydrogen that could theoretically be used for fusion, and helium byproduct of fusion does not harm the environment, so some consider nuclear fusion a good alternative to supply humanities energy needs. Experiments to generate electricity from fusion have so far have only partially succeeded. Sufficiently hot hydrogen must be ionized and confined. One technique is to use very strong magnetic fields, because charged particles (like those trapped in the Earth's radiation belt) are guided by magnetic field lines. Fusion experiments also rely on heavy hydrogen, which fuses more easily, and gas densities can be moderate. But even with these techniques far more net energy is consumed by the fusion experiments than is yielded by the process.

nuclear fission

nuclear fission is either a nuclear reaction or a radioactive decay process in which the nucleus of an atom splits into smaller parts (lighter nuclei). The fission process often produces free neutrons and photons (in the form of gamma rays), and releases a very large amount of energy even by the energetic standards of radioactive decay.
Nuclear fission of heavy elements was discovered in 1938 by Lise Meitner, Otto Hahn, Fritz Strassmann, and Otto Robert Frisch. It was named by analogy with biological fission of living cells. It is an exothermic reaction which can release large amounts of energy both as electromagnetic radiation and as kinetic energy of the fragments (heating the bulk material where fission takes place). In order for fission to produce energy, the total binding energy of the resulting elements must be greater than that of the starting element.
Fission is a form of nuclear transmutation because the resulting fragments are not the same element as the original atom. The two nuclei produced are most often of comparable but slightly different sizes, typically with a mass ratio of products of about 3 to 2, for common fissile isotopes. Most fissions are binary fissions (producing two charged fragments), but occasionally (2 to 4 times per 1000 events), three positively charged fragments are produced, in a ternary fission. The smallest of these fragments in ternary processes ranges in size from a proton to an argon nucleus.

An induced fission reaction. A neutron is absorbed by a uranium-235 nucleus, turning it briefly into an excited uranium-236 nucleus, with the excitation energy provided by the kinetic energy of the neutron plus the forces that bind the neutron. The uranium-236, in turn, splits into fast-moving lighter elements (fission products) and releases three free neutrons. At the same time, one or more "prompt gamma rays" (not shown) are produced, as well.



source:wikipedia.org  ,  youtube.com