HOW DO WE GET DRUNK ?

There are actually many kinds of alcohol in the chemical world, but the one we drink the most is ethanol. It's the particular shape of an ethanol molecule that gives a glass of beer or a shot of the hard stuff its specific effects on the human brain.The molecule is very tiny, made up of just two carbon atoms,six hydrogen atoms, and one oxygen atom.
Ethanol is water soluble,which means it enters the blood stream readily, there to be carried quickly to all parts of the body (most notably the liver and the brain). It's also fat soluble; like an all-access pass through various cell membrane sand other places that are normally off limits.

A certain portion of the ethanol you drink passes through your stomach to your small intestine,
then absorbed into your blood stream and carried to your brain.That's what we're really concerned with. Research has not conclusively determined exactly how ethanol accomplishes all of its various effects in the brain,but there are some well-supported theories. The slow reactions, slurred speech and memory loss of a drunk are probably caused by ethanol attaching to glutamate receptors in your brain's neural circuitry.These receptors normally receive chemical signals from other parts of the brain, but instead they get an ethanol molecule.This disrupts the flow of signals and generally slows the whole brain down.

Ethanol also binds to GABA ( gamma-aminobutyric acid) receptors,which normally serve to slow down brain activity.
Unlike glutamate receptors, ethanol actually makes GABA receptors more receptive, causing the brain to slow down even more.
But alcohol isn't simply a depressant, because it also stimulates the production of dopa mine and endorphins, chemicals that produce feelings of pleasure. Research hasn't yet revealed the exact mechanism involved, but it may be similar to the way ethanol stimulates the GABA receptors.

WHAT'S INSIDE THE HEART ?

Your heart is a turbocharged double ¬ pumping muscle that beats more than 40 million times every year

Not only does your heart do amazing things, it does so tirelessly, every minute of every day from the moment you're born (actually, even a bit before then) to the instant that you die.It weighs somewhere between eight and 12 ounces - slightly more if you're male,less if you're female. Its sole purpose is to push blood through your circulatory system, providing crucial oxygen and other nutrients to all your organs.

The heart is considered a double pump because the right half sends 'used' blood to your lungs.There, the blood drops off a load of carbon dioxide and picks up some fresh oxygen, which you have helpfully provided by breathing.Then the oxygenated blood returns to the left half of the heart.This 'heart-to-lungs-to-heart again' trip is known as pulmonary circulation.The left side of the heart then pumps this oxygenated blood to every organ in your body other than your lungs.
Your brain,your skin, the musclesin your thigh,yourspleen-theyall get blood (and therefore oxygen) by virtue of your beating heart.

Even the heart itself gets blood, via a special set of veinsand arteries known as the coronarysystem.The myocardial muscle within the wall of the heart needs oxygen and other nutrients to keep beating. Unfortunately, the coronary arteriesthat do this jobarevery narrow, between1.7and 2.2 millimetres in diameter. If they become clogged with cholesterol or other fatty deposits, the
heart stops working.This is bad for you.

Of course, the relatively simple concept of the double pump is fairly complex in practice. A series of valves control blood flow to the heart's four chambers, allow for the build-up of enough blood pressure to get the job done,and direct the blood to the correct veins
and arteries.

HOW DOES A CAMERA TAKE PICTURE ?

Many camera owners are content to shout "Cheese" and push the shutter button to get an image, but we go under the hood to find out how it happens

There is no doubt that the digital format has revolutionised the imaging industry and in turn the way we work our cameras.Furthermore the internal DNA of the camera has been entirely restructured to make way for the new electrical system...or has it? In fact film and digital cameras operate in a similar manner.Varying the size of the lens's diaphragm(aperture) in tandem with the amount of time the shutter is open, focusing light onto the image detection material...the only difference is that now received in an electrical rather than chemical form. A DSLR (digital single-lens reflex) camera employs a mechanical mirror system that directs the light travelling through the attached lens upwards at a 90-degree angle allowing the photographer to compose the shot through the viewfinder.As the shutter button is pressed the exposure takes place: the mirror swings out of the way and the shutter opens allowing the lens to project the light onto the image sensor.

In low light scenarios the shutter will need to stay open for a longer period of time for the image to be recorded, which is why photographers support their cameras with tripods as the smallest degree of camera shake will disturb the quality.

The sensor is formed of millions of pixels laid out in thousands of rows and columns: the more pixels or dots of light, the higher the megapixel count and in theory the higher the resolution. The light travels through a col our filter above the sensors and is converted from light waves in to an analogue signal which is then processed through a digital convertor. Next the conversion is fine tuned through a series of filters that adjust aspects such as white balance and colour.The resulting image can be made in to a JPEG by compressing the file size and discarding unnecessary pixels.The final image is shown on the LCD.

WHAT IS GRAVITY ?

Surprisingly weak yet mysteriously powerful, gravity is the super glue of the universe

Everything in the universe is made of matter the cosmic 'stuff' of creation. Mass is measurement of the amount of matter contained in any object, from planets to protons.

The Earth, for example,has a mass of 5.9742 x 1024 kilograms,while the mass of a single proton is 1.67262158 x 1027 kilograms.

When we think of gravity,we usually think of the gravitational force exerted by massive celestial bodies like the Earth,the Moon or the Sun.But the truth is that any object of any mass-even a sub-atomic particle- exerts a gravitational pull on near by objects.

Sir Isaac Newton proved that objects of greater mass exert a stronger gravitational force.That's why we typically talk about gravity in reference to planet sand not protons.

But the shocking truth about gravity is that even a colossal hunk of rock like the Earth exerts an exceptionally puny pull.An infant,in fact,can defeat the combined gravitational pull of every single atom on the planet by simply lifting a wooden block off the floor.

That's what makes Newton's discoveries so amazing,even today.Gravity-this wimp of a force-is somehow powerful enough to pull the moon in to orbit and keep the Earth cruising in a perfect elliptical path around the Sun.Without the constant tug of gravity,planets would crumble into dust and stars would collapse.

Gravity is also responsible for giving objects weight.But don't confuse weight with mass. While mass is a measurement of the amount of matter in an object,weight is the downward force exerted by all of that matter in a gravitational field.In the zero-gravity vacuum of space, objects are weightless,but they still have mass.

On the surface of the Earth, where the force of gravity is essentially constant,we consider mass and weight to be equal.But that same object-with the same mass-will weigh 17 per cent less on the Moon,where the gravitational pull is weaker.On Jupiter-not the best place to start a diet- that same object will weigh 213 per cent more.

HOW DOES THE OZONE WORK?

 We may hear about it a lot, and mainly how we're slowly destroying it, but just what is the ozone layer?

The ozone layer is essentially Mother Earth's safety net. residing some 50 kilometres above the planet's surface. created from O3 or ozone gas,it is up to 20 kilometres thick and 90 per cent of this gas can be found up on the Earth's stratosphere.
This protective gas is vital to the nurturing of life on our planet,and here's why.
Ozone gases act as a shield against ultraviolet,or UVB, radiation. These harmful emissions are sent through the Sun's rays,and without the ozone would severely affect the planet's ecological balance, damaging bio-diversity.UVB rays reduce plankton levels in the ocean,subsequently diminishing fish stock.Plant growth would also diminish in turn disrupting agricultural productivity. This would in turn affect the human populace,who would be exposed to an increase in skin-related diseases such as cancer.

So how does the ozone protect us? Ozone molecules consist of three oxygen atoms, hence the chemical formula O3.Stratospheric ozone absorbs UVB high-energy radiation,as well as energetic electrons, which in turn splits the O3 in to an 0 atom and an O2 molecule. When the 0 atom soon encounters another O2 molecule they re-merge and recreate O3.This means that the ozone layer absorbs the UVB without being consumed.The ozone layer absorbs up to 99 per cent of the Sun's high frequency UV light rays, transforming this in to heat after its combustible atomic reaction,therefore creating the stratosphere itself.This effectively incubates life on Earth.
But ozone doesn't reside only in the world above.
This gas is also present in the layer around the Earth's surface.Ten to 18 km above us, this is known as the tropospheric ozone or 'bad ozone',comparative to the function of the stratosphere.
This ozone occurs naturally in small doses, initiating the removal of hydrocarbons,released by plants and soil,or appearing from small amounts of stratospheric ozone,which occasionally migrate down to the Earth's surface.
However,it gets a bad reputation due to its interaction of ultraviolet light, with volatile organic compounds and nitrogen oxides,emitted by fossil-fuel powered machines and internal combustion engines. The produces high levels of ozone which are formed in high temperature conditions, ultimately toxic to all forms of organic life.

WHAT DOES THE LIVER DO ?

The human liver is the ultimate multitasker - it performs many different functions all at the same time without you even asking

the liver is the largest internal organ in the human body and has over 500 functions. In fact it's the second most complex organ after the brain and is involved in almost every aspect of the body's metabolic processes.Its main functions are energy production, removal of harmful substances and the production of proteins.These tasks are carried out within liver cells called hepatocytes, which sit in complex arrangements to maximise efficiency

The liver is the body's main powerhouse, producing and storing glucose as a key energy source.It is also responsible for breaking down complex fat molecules and building them up into cholesterol and triglycerides,which the body needs but in excess are bad. 

The liver makes many complex proteins, including clotting factors which are vital in arresting bleeding.Bile,which helps digest fat in the intestines, is produced in the liver and stored in the adjacent gallbladder.

The liver also plays a key role in detoxifying the blood. Waste products, toxins and drugs are processed here into forms which are easier for the rest of the body to use or excrete.The liver also breaks down old blood cells, produces antibodies to fight infection and recycles hormones such as adrenaline. Numerous essential vitamins and minerals are stored in the liver:vitamins A, D, E and K, iron and copper.

Such a complex organ is also unfortunately prone to diseases.Cancers (most often metastatic from other sources),infections (hepatitis)and cirrhosis (a form of fibrosis often caused by excess alcohol consumption)are just some of those which can affect the liver. 

HOW DO KIDNEYS FUNCTION ?

Find out what your kidneysare doingto keep you alive

Kidneys organs the back are situated just bean-shaped under halfway the down
ribcage, one on each side of the body,and weigh between115and 170 grams each, dependent on the individual'ssex and size.The left kidneyis commonlya little larger than the right and due to the effectiveness of these organs, individuals born with only one kidney can survive with little or no adverse health problems. Indeed, the bodycan operate normallywitha 30-40 per cent decline in kidney function.This decline in function would rarely even be
noticeable and shows just how effective the kidneysareat filtering out waste productsas well as maintaining mineral levels and blood pressure throughout the body.The kidneys
manage to control all of this by working with other organsand glandsacross the bodysuch as the hypothalamus, which helps the kidneysdetermineand control water levels in the body.
Each day the kidneys will filter between150and180 litres of blood, but only passaround two litres of waste down the ureters to the bladder for excretion.Thiswaste product is primarily urea-a by-product of protein being broken down for energy -and water,and it'smore commonly known as 'urine'.The kidneys filter the blood by passing it through a small filtering unit called a nephron. Each kidney hasaround a million of these, which are made up of a number of small blood capillaries, called glomerulus,and a urine-collecting
tube called the renal tubule. The glomerulussift the normal cellsand
proteins from the blood and then move the waste products into the renal tubule, which transports urine down into the bladder through the ureters.
Alongside this filtering process, the kidneysalso release three crucial hormones (known as erythropoietin, renin and calcitriol) which encourage red blood cell production,aid regulation of blood pressure and help bone development and mineral