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The Solar Powered Slug

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I've often wondered what it would be like if we could make our food the same way plants do. Could I make glucose for respiration by walking around outside in the sunlight, not that we get much where I live? Of course, I would be green, but perhaps only where my skin is exposed to the sun. Photosynthesis is the chemical reaction plants use to make their food. They take in water from the soil and carbon dioxide from the air and, using sunlight for the energy, they turn this into glucose and oxygen. The name for a reaction that takes in energy is endothermic. Photosynthesis is an exothermic reaction. You may have used a reaction like this if you have ever injured yourself. You can get cool packs which cool down when you mix two chemicals. Chloroplasts in a Cell Plants can collect sunlight for photosynthesis because they have structures in their cells called chloroplasts, (above). Chloroplasts contain a chemical called chlorophyll, which absorbs light energy so that the photosynthesis

Barcoding the Stars

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Looking up at the night sky, you will see dozens of stars. If you live in a very dark place, you may even see hundreds. The thing that people find difficult to grasp is just how far away these stars are. Our sun is 150 million km away from earth. If you could travel at the speed of light, which is as fastest you can go, it would take 8 minutes to get there. To get to the next nearest star at the speed of light, you would be travelling for 4 years (that's without toilet stops). Other objects are much further away. There are billions of galaxies outside of our Milky Way. Light from one of the nearest takes over 2 million years to reach earth. That is truly a galaxy far, far away. This is the Andromeda Galaxy, the farthest object you can see with the naked eye. We can't get to the stars to study them, so how do we find out how they work? The answer is light. We use telescopes to collect light from the stars and watch them move and change. Some telescopes detect light that we can&#

The Man With Golden Blood

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I like to cook, which usually involves knives. One afternoon I was chopping onions when I unexpectedly removed the tip of my finger. Naturally, I was alarmed at the amount of blood, and I began to wonder if the bleeding would stop but stop it did. Magic? No, your blood has ways of stopping bleeding. Good job, too; it's important stuff. Blood looks like a simple liquid, but it is complicated and carries out several jobs. You may know that red blood cells are carried around in a liquid called plasma. You may also know that these cells contain a chemical called haemoglobin, which gives them their red colour. These little packets move around your circulatory system, transferring oxygen to where it is needed and returning to your lungs to pick up more. Also carried in the plasma are your white blood cells. There are many kinds of these, but they protect you from dangerous invaders. They identify foreign organisms, bacteria, viruses, fungi, or transplanted organs. Once identified, they

The Man with a Hole in His Stomach

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When I was a child, we had the usual family myths. These included don't drink milk after eating an orange, it will curdle, don’t sit on the cold step or you’ll get king cough (I never found out what that is), and boiled onions in milk stop you from catching a cold (it may just keep people away from you, so you don't catch anything). There was also an obsession with getting enough fibre, which isn't necessarily a bad thing, but it's extreme when you get interrogated about it when visiting your nana. Are any of these ideas true? How can we find out? Part of the science you study in school is how your body works. A vital organ system is your digestive system, not that the rest are unimportant. We don't usually think about what happens after we swallow our tea unless something goes wrong, but an awful lot is happening that we can't see (believe me, that’s a good thing). Most of the chemicals in your food are useless until your digestive system changes them. The prop

Escape the Solar Wind

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Hang a bar magnet on a piece of thread and wait until it stops moving. One end will eventually point to the north pole of the Earth. This happens because the earth is a giant magnet, and your magnet is lining up with the Earth's magnetic field, which surrounds our planet like a giant bubble and allows us to find our way around. A magnetic field is an invisible force field that surrounds magnets. Other magnets and some metals are influenced if they come into the magnetic field. The magnetic field around a bar magnet is called a butterfly diagram. Perhaps you can see why. The field is why a magnet will stick to a fridge, or two magnets may push each other away. Each magnet’s magnetic field interacts with the other’s, causing attraction or repulsion.  The ends of a magnet are called poles. One end is called the north-seeking pole, and the other is the south-seeking pole. We usually shorten these to north and south. Put two poles that are the same together; they will repel. A north and

Why are my bandages moving?

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There's nothing quite as stomach-churning as a pile of maggots. I used to work with someone that was into fishing. He would buy a box of them and put it in the lab fridge. Once or twice the lid came off, and we were met with a squirming mess when we opened the door. That's not counting the time he forgot they were in there, and they turned into flies.  We are naturally disgusted by some things because they spread diseases. Flies, vomit, puss, the list goes on. Would you be surprised if you went into a hospital and a doctor prescribed maggots to help heal a wound? That's right, maggots!  People with badly infected wounds can be prescribed maggots to help clean them. These particular maggots have been raised in sterile conditions, so please don't go rooting in the dustbin at home.  How does this work? Warning you shouldn't read this before your tea! Maggots like to eat dead or rotting material. That’s precisely what is in some nasty wounds. These wounds can be infecte

Lucy in the Sky With Diamonds

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You may have heard that diamonds are a girl`s best friend or are forever, but have you ever heard of these shiny pieces of bling falling from the sky as rain? Diamonds are also well known for being super hard, so much so that they are attached to the tips of drills to cut through the toughest materials. Where, then, would you find liquid diamonds? That`s right, liquid!  One of my favourite pastimes is to read about and listen to podcasts about the planets. Why is this subject so fascinating to me? Apart from the fantastic photographs that spacecraft have sent back from these objects, some of the ways they work are unlike anything we will ever see on Earth. In the solar system, temperatures and pressures never occur naturally on our planet. This means that substances we are familiar with do strange things elsewhere in the solar system. For example, ice far away from the sun`s influence gets so cold that it behaves like rock. Methane, the gas used for cooking and heating, can be a liquid