URINARY SUSTEM OF MAN

A pair of kidneys consist of millions of functional units,nephrones.The nephrones have extensive blood supply via the renal arteries,which leave each kidneys via the renal veun.The function of kidneys and blood in clearing waste is very evident from the fact that weight of kidneys accounts for less than1% of the total body weight while receive 20% of blood supplied with each cardiac beat.following filtration of blood and further processing through tubular system urine is collected in the central cavity of the kidney,pelvis.Urine leave the kidneys through a duct ureter.The uriters of the both the kidneys drain into urinary bladder throgh ureteral orifice.Urine leave the body during urination,from a bladder through the tube urethra,which empties near the vagina in female or through penis in male.sphincter muscles near the function of the urethra and the bladder control the urine in bladder.

Human urinary sysytem

NEPHRON: The functional units,nephrones in human kidneys are arranged along two distinct rigions, an outer cortex and an inner medulla.The nephrones arranged along the cortex are called as cortical,However those arranged along the border of cortex and medulla with with their tubular system looping deep in inner medulla are JUXTAMEDULLARY nephrons.The juxtamedullary nephrone are specifically instrumental in the production of concentrated urine.In each nephrone inner end form a cup shaped swelling called BOWNAN,s capsule and it is around a ball of capillaries called

The structure of a kidney

GLOMERLUS.Glomerulas circulate blood through capsule as it arrives through afferent arterilos and leave the capsule by afferent arterioles. The blood vessel subdivides again into another network of capillaries the PERITUBUKAR capillaries. Bowman capsule continuse as extensively convoluted proximal tubule, loop of Henle and the distal tubes, which empties into collecting tubules.The collecting tubules open into pelcis. The filtrate from glomerulas passes through these structure and is processed ultimately for urine formation .

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USES OF VARIOUS DEVISES (INPUT,PROCESSOR,OUTPUT)

ELECTROIC DEVICES ARE MAINLY OF THREE TYPES.

(1) INPUT  (2) PROCESSOR  (3)  OUTPUT (1)       INPUT DEVICES  Any devices that change non electrnical enery into electrical energy in an electronic system is caleed an input devices.A microphone is an input devices.It converts sound into electrical signal.similarly, an electronic camera also converts a picture to electrical signals.Both are input devices.Other example of input devices are the keyboard and mouse which ate used to enters information into a computer.scanner is also an input fevices. These feed information,pictures and documents etc.to the computer in the form of electrical signals.

• (2) PROCESSOR     A processor is the main component in an electronic system that converts the input into output.Amplifier tape recorder telrvision etc.are also common processor. The amplifier increase the energy of electrical signas of sound fed by the microphone and send them to the loud speaker.The television converts the electrical signals fed to it through antena or vable. Into pictures and sounds. The microprocessor of aa computer is very good example of it.it controls the different parts of computer to display output result on the screen of monito.

1. (3)  OUTPUT DEVICES  an output device convert electric am energy into other form of energy.For example, a loud speaker convert electrical signals into sounds so it is an out put devices the screen of TV is also an output device .It converts electrical signals into pictures.The output devices of a computer system are the moniters and printers.The output component of various devices ate widely used in our schools and surroundings.Electrical appliances such as tape recorder, TV computers, meters and electrical bells are commonly used in homes and schools.Loudspeaker are used in maajid, halls cinemas and rheaters. Robots are used in the favtouries for mega projects.

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IMAGE FORMATION IN SIMPLE CAMERA AND HUMAN EYE

We know that if an object is lying at a distance more than the focal length of a convex lens,its real and inverted image is formed on the other side of lens.The image through the eye and camera is formed in the same way.Let us compare the structure and function of both of them.
CAMERA.  camera is a kind of box to which q convex lens is mounted on the front side.The lens form a real and inverted image of an object on a sensitive image film placed behind it.A system is provided in a camera to move the lens back and forth so that Sharpe image is obtained on the film. There is shutter behind the lens that remains close normally.When the button is pressed the shitter is open for a while light coming from the object enters the camera during this intervals an image is firmed on film. The amount of light enters the camera depending upon the size of aperture. Aperture is an opening in the diapharam behind the lens.This can be made smaller or larger as required. The pictures is obtainer by developing the image on thelens.HUMAN EYE.   The human eye also work like a camera.The eye is almost a sphere of diameter about 2.5cm.Its outer boundary called the sclera is thik and hard.At the front of eye there is a trasparrent hard skin known as cornra. Behind the cornea there is iris and after that there is convex lens.The inner layer of the back wall of eye is called retina.The retina of eye and the films of camera serve the same purpose.Like camera,the eye lens form a real and inverted image of the object on retina.The optic nerve carries it on the form of signals to the brain. Although the image for end on retina is inverted but our brain interprets this correctly,i e ,the right way up.The iris acts like the diaphragm of camera.The opening at the center of iris is called pupil which is just like aperture of a camera.when the light outside is dim, the iris contracts to make the pupil largers so that more light can can enter the eye.In bright ligt, the irices makes the pupil smaller. 

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Important biotechnology technique

Gene Therapy gene therapy is an advanced biotechnological technique which is used to cute genetic and acquired disease like cancer and AIDS.In this process,defective genes are supplemented or replaced by normal genes.

Genetic Testing genetic testing is one of the latest biotechnologocal techniques used for genetic diagnosis of inherited diseas.It involves the direct examination of DNA molecule.Itbis also used to determine a child's paternity or a persos ancestry.
Coloning. coloning is also amongst the latest biotechnology techniques used in various types of genetic analyses.Animal coloning can be used for production of animal organ,and strong,well built livestock for quality production of milk and meat

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GENETIC MODIFICATIONS AND BIOTECHNOLOGY PRODUCTS

The change in the genes of organisms using biotechnology techniques is called genetic .The change in the genes of organism can be produced by removal,addition or modification of genes.It is the modern method to change the character of organism.FOR EXAMPLE,this process is used in crops to develope resistance in plants against disease causing microorganisms.The organism whose genes are modified is called GENETICALLY MODIFICATION ORGANISM (GMO).GMOs are also used to prepare useful and life saving products such as insulin and vaccine, etc.

Production of insulin by genetically modified bacterium

• INSULIN  insulin is an animal protien,which is produced by pancreas.It controls the glucose level in blood.If pancreas does not produced the required amount of insulin,the level of glucose in blood rises.This condition is known as diabetes mellitus iastimulateACCINES.  Vaccine is a material which contain weekend or killed pathogenesis and is used to produced immunity against disease.when vaccine is injected into the body of person the blood cells in the body take the weak or dead pathogenes as real ones and prepare antibodies against them. These antibodies remains in blood.when any real pathogens enters the bofy, the already present antibodies kill it immediately and the body become protected from disease.Nowdays, biotechnologists used bacteria to prepare vaccine they identify some protein of pathogens that that do not cause disease but can stimulate blood cells to make stimulate blood cells to make antibodies.The gene of some protein is inserted into bacterium. The GM bacteria make colonies and prepare the pathogenes protiens. These protiens act as protiens. When these proteins are injected in human body its blood cells produce antibodies. These antibodies can kill the kind of pathogens from which the gene was taken.

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