What is life? This is what scientists have been asking themselves for years. Now, to determine if something is alive or not, characteristics of life have been developed. For something to be considered alive, that something must have all the characteristics, not just one or two. If it does have all the characteristics, it is called an organism.

There are many different versions of these characteristics available, which doesn’t make sense. I compiled a list by comparing the many lists I saw. This is what I believe to be an ultimate list from several lists.

1. Organisation: This characteristic doesn’t mean that living things should be organised in their daily life but chemically. They have to be composed of atoms, which form molecules, which form cells.  Similar cells put together make a tissue, and two or more tissues make organs. Organs then make a system. A living thing doesn’t have to have a system, but at least one cell. These are called unicellular organisms (e.g. Amoeba). If the living thing has more than one cell, it is called a multicellular organism (e.g. Cat, Human).

Example: Muscle cells->Muscle Tissue->Heart (an organ made up of muscle tissue)->Circulatory System (Lungs and Heart and Blood Vessels working together)

2. Growth: All living things should be able to gather resources to use them to make their cells bigger, making their entire system enlarge.

3. Reproduction: All living things should be able to create another of its species. If it couldn’t, species would not be able to survive because no young would be born to keep the species going. There are two kinds of reproduction: asexual and sexual. Asexual involves only one parent, for example, bacteria dividing their cells in two, creating two new beings. Sexual involves two parents.

4. Movement: All things should be able to move in some way. It is noticeable that a human, dog, centipede, can all move, but then what about plants? Plants move, only they move so slowly it is only noticeable after a certain number of time. For example, sunflowers move into the direction of the sun, flowering plants open their petals. The roots move down into the earth. Although it is not obvious, like a running animal, plants do move.

5. Response: Response is when an organism has the ability to respond to changes in its environment and to things happening in their bodies. Organisms respond to light, sound, and touch. Again, plants do not seem to be responding much, when you pull of one of their leaves, they don’t jump back from shock and pain. But plants do respond. They have no nervous system, so they won’t respond to touch, but they grow toward the light. If the sun changes place, they adapt themselves so that they end up back towards the sun. Another example would be that if a seed that is growing finds itself the wrong way, with its roots in the air, then the plant will respond to gravity and shift so that it’s roots are back down in the earth.

6. Respiration: Respiration is how organisms get and use their food. There are two types of organisms for this characteristic: Autotrophs and Heterotrophs. Autotrophs are organisms that create their own food, i.e. plants. Heterotrophs are organisms that get food by eating other organisms, i.e. animals.

7. Metabolism: This is how an organism uses it’s food, which food it requires, and how much of it it requires, and also what is poisonous to the organism. It is also the ability to create energy, and to divide it for separating it into different parts of the organism. A living thing must be able to metabolize.

All these characteristics must be present in something for it to be an organism, otherwise it is not alive. Is a cellphone alive?  It reacts with it’s environment (when you press buttons), it moves when it vibrates, but does it reproduce or break down its food to make energy?

Reference: http://en.wikipedia.org/wiki/Life,

http://wiki.answers.com/Q/What_are_the_7_characteristics_of_life

http://edhelper.com/ReadingComprehension_37_158.html

http://en.wikipedia.org/wiki/Metabolism

http://bit.ly/a2HcIm

http://bit.ly/ctPcRv

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Marie Sklodowska was born in Warsaw, Poland on the 7 of November 1867. Known as a great scientist who discovered two new elements (Polonium, Radium), she was also the first woman to receive a Nobel Prize, as well as the first person to receive two Nobels in her lifetime. At a young age she moved to Paris where she became a governess to help her sister pay her college funds, who when finished, returned the favor and she aided Marie to pay the entrance fee of the Sorbonne. There she met Pierre Curie, another fellow student interested in science. They married and later had a total of two daughters, Irene and Eve. Mary and Pierre both joined forces and studied radioactivity, from where they discovered radium. Pierre died on the rainy Thursday 19 of April, 1906 from a road accident. Marie was devastated and depressed and she sought companionship in her late husband’s best friend, Paul Langevin. Media exposed her affair and it practically destroyed her reputation and all she had achieved so far. And since she was a woman, her achievements were mostly seen as Pierre’s achievements (the man) and when he died, she was supposed to accept the government’s offer of a pension to support herself and her children. She boldly refused and took her husband’s job as a professor at the Sorbonne, and she continued her researches. After the media outbreak concerning her affair, she fought hard to be respected again. Then her second Nobel was given to her and she was cast in a new light. She concentrated on finding healing powers with radioactivity and she even went to battlefields during WWI to X-ray the wounded soldiers and find the bullet fragments. She saved many lives. She set up an institute and continued her life successfully, though she would not acknowledge the fact that radium was dangerous and could cause illness. She died on July 4, 1934, in France due to exposure to radioactive substances and pure radium most of her life. Irene, her first daughter, followed in her mother’s footsteps and she too received a Nobel in science, along with her husband. Eve went down the literature path and she published the first biography of Marie Curie.

Reference:

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Since I was in my molecules and atoms period, I also tried doing this experiment: Measuring the Diameter of a Molecule. The experiment was found on a school website. I read the essay summarising the experiment and I thought the concept was pretty simple. It was basically filling out a rectangular straight-sided pan with water and to make sure the water bulged over the side of the pan. Then a wire rod was to be placed over the water near the middle of the pan. It had to just lightly touch the water. A single drop of oil was to be dropped into the middle of 1 section created by the rod. The oil was then to spread out over the surface of the water and when it had covered the whole surface between the side of the pan and the side of rod, the rod was to be moved another couple of inches to allow the oil to spread even more. It continued liked this until you were supposed to see the oil starting to break up and see fissures in what should look like a very thin blanket of oil over the water. As soon as this happened the rod must be left alone and the length and width of the oil blanket must be measured. The idea was that all the molecules started spreading out and just before the cracks could come, they would all be flatly the one beside the other, making the oil one molecule thick. A calculation was then given out to find out the height of these molecules. Volume=Length*Width*Height

××

Assuming the drop was 1 cubic millimetre and the oil’s length was 400 mm and the width was 300 mm:

××

×

×

0.00000833mm is the supposed height of one oil molecule. If you want more details on this experiment, visit the site, but details were my exact problem.

When I tried this experiment I did everything the experiment told me to do. The thing is, it doesn’t tell you a lot. A lot of variables that need to be known are not explained, for example, the type of oil, the amount of time the experiment takes, or even the water temperature. I used olive oil because it was the only oil I had. I wasn’t able to reproduce this experiment even though I tried three times. The first time I used ambient temperature water and a tiny drop of oil from the tip of a needle. It didn’t work. The second time I used ambient temperature water again but this time with a slightly larger drop which I think was roughly 1 cubic mm. I used a pipette for the drop this time. This time it seemed to actually spread but it spread out into a bigger drop VERY SLOWLY. I left it overnight and in the morning the drop had clung on the edge of my pan and it had broken down into several bubbles. The third time I used the same amount of oil but I used hot water. This time the drop didn’t even bother spreading.

My conclusion is that I have no idea if the proposed answer they gave could be right or if it is downright wrong. If it is wrong then the experiment was probably found somewhere else and it was probably not carried out before putting it on their website. If it is right, then whoever wrote out the experiment did not do it properly because I could not carry it out due to missing details.

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Electricity is a general term for a wide range of events resulting from the presence or flow of an electric charge. These events could be things commonly known such as lightning or static electricity, but an other event possible could be electromagnetic fields. People have been aware of the shocks they received from electric fish and eels for a long time. Old Egyptian texts found named these fish as ‘Thunderers of the Nile’ and they were proclaimed as the ‘protectors’ of all fish. Later on, Ancient Greek, Roman and Arabic physicians wrote about these fish. They knew of the numbing effect of the shocks, and they knew the shocks could move with conducting objects. These electric fish were used as medicine to cure gout or headaches. The theory was that the sudden shock would shake away the sickness. Thales of Miletos made a series of observations around the year 600 BC concerning static electricity. He believed the static was because the objects he rubbed became magnetized because of friction. After him, electricity was no more than an abstract curiosity for millennia until 1600. In the early 19th century, the work became more precise and extensive experiments and observations were made. In the late 19th century, electricity was discovered and it became a tool in science and modern life instead of a scientific curiosity. People like Nikola Tesla and Thomas Edison showed up and electricity became a necessary force for the Second Industrial Revolution.

Electricity comes from atoms. The protons and neutrons create the center, the nucleus. The protons are positively charged and electrons, which rotate around the nucleus, are negatively charged. The neutrons, hence the name, are neutral. They are not charged. The actual electricity comes from when the electrons move from one atom to the other. Negatively-charged electrons are always attracted to positively-charged protons.

Some atoms are excellent at conducting because there are tracks which the electrons follow. The electrons mostly stick to the closest track to the nucleus because it requires less energy. If the track the most extended to the outside is clear enough of other electrons, the electrons can jump from one track to another and exit their previous atom to enter a new one. These atoms are Conductors. If the track isn’t clear or if the atom holds on tightly to it’s electrons, the electrons cannot move and no electricity is created. Another reason why some atoms conduct better than others is because of their Atomic Number. This number is written on the periodic table of the elements, and it basically tells you how many protons are in the nucleus of one atom from that element. The positively-charged protons attract negatively-charged electrons, making the passing from one atom to the other more tempting and once the electrons are moving, the attraction makes it easier for them to move.

References: http://en.wikipedia.org/wiki/Electricity,http://www.pbs.org/transistor/science/info/conductors.html,http://en.wikipedia.org/wiki/Atomic_number,http://www.pcguide.com/ref/power/ext/basicsWhat-c.html

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An atom is the smallest piece of an element which still has the element’s chemical properties. They are made up of smaller particles called protons, neutrons and electrons. The protons and neutrons bond together in the middle to form the nucleus and the electrons rotate around this nucleus in a cloud. The ratio of protons to neutrons is unique to one sort of atom. An element is lots of atoms, but they all contain the same amount of protons to neutrons. If two sorts of atoms combined, a compound would be created. Some different sorts of atoms are glad to bond together and form molecules (oxygen + chlorine), but others do not bond very well (neon + argon).

A molecule is made up of at least two atoms held together with very strong chemical bonds. These bonds are made because of the constant passing of electrons between atoms. A molecule is the smallest particle, next to atoms, in a chemical compound or element that actually has the chemical properties of that compound or element.

If you find this hard to understand, visualise a pile of paper clips which are all the same. They all have the same colour, size, and weight. If you divide your pile into two separate equal piles, and divide those piles in two, eventually, you will have one paper clip per pile. These can represent an atom. Your paperclip is still useable (i.e. it still has it’s chemical properties), but if you divide even more by cutting the paper clips in half, they won’t be able to actually hold paper. Now visualise a different pile of paper clips, but they are all still the same. Separate them down like the first pile and you get your atoms. Then take a paper clip from each pile and clip them in together. You have now created a molecule, i.e. two atoms joined chemically. The full pile of all the same paper clips (atoms) would represent an element.

References:http://education.jlab.org/qa/element.html,http://science.howstuffworks.com/atom1.ht, http://en.wikipedia.org/wiki/Molecul,http://whatis.techtarget.com/definition/0,,sid9_gci856651,00.html

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My newest plant, called Asplenium, is a fern which grows on trees, stones or sometimes independently in the soil. Asplenium contains about 700 species. A common name applied to the most typical plants is “Spleenworts”. Both this term and the scientific term come from an old belief that these plants were useful ailments for spleen problems, due to their spleen-shaped leaves. And as for “Worts”, it is an old english term for “plants”.

After a little research, I found that my plant is an “Asplenium Australasicum“. It is found in Queensland, New South Wales and Asia. Its common name is “Crow’s Nest Fern“. Its habitats are rainforests and it is used to the harsh conditions and recovers quickly with the help of rain. The unusual positioning of leaves helps the plant to catch dead leaves and waste from around it so that it can create it’s own serving of compost.

This plant is often confused with “Asplenium Nidus“, the ‘Bird’s Nest Fern‘. Contrarily to the Crow’s Nest Fern, its foliage is edible and is largely eaten in Thai food.

The roots are relatively small compared to the size of the plant, this makes it an ideal indoor plant (the roots have space in the pot). Avoid putting it in full shadow, but do not over-expose to sunlight. Keep the soil moist but don’t drown your plant. As well as watering regularly, spray a little once a week to keep the leaves moist as well.

Sources: http://bit.ly/7ghqNZ, http://bit.ly/6f00Yx

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On a visit to Ikea, I bought a plant called “spathiphyllum”. Here’s some background information on the origins of this beautiful plant and how to take care of it.

Native to tropical regions of the Americas, and southeastern Asia, these plants are more commonly known as “Peace Lilies”. Spathiphyllum is composed of about 40 species. I am unsure of the exact type of Peace Lily I now own.

It is commonly known that this plant belongs to a group of plants that filter pollutants in the air as well as taking in our carbon dioxide and giving us oxygen back. Other studies have proven that plants in offices have reduced the amount of headaches, and coughs. The Peace Lily was part of the group of plants tested and it was proven that indoor air was cleaner with this plant. They also can bring an increase in well-being. If you cannot have an animal companion, then a plant will brighten up the room and they need to be taken care of if you want them to look the best.

For the Peace Lily, it doesn’t like direct sunlight and thrives mostly in partial shadows. Keeping the soil moist is important but drain the excess water that is left at the bottom of the pot. When the flowers bloom and wilt, cut them off and another flower will grow back again. This is a tropical plant and it likes temperatures above 15℃ (59℉). Also keep them out of drafts. Love them and they will love you.

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On the 28th of November 2009, I went to a 1 day seminar at the National Museum of Ireland, celebrating the 200th anniversary of Charles Darwin, and also celebrating the 150th anniversary of his most famous book on evolution, “On the Origin of Species”.

Charles Robert Darwin (1809-1882) was born on February 12th in Shrewsbury, England. The son of Susannah and Robert Waring Darwin, he was born into luxury. He was the second youngest of six children. He attended school at Shrewsbury and ever since he was little he liked to collect things. Not only insects, but stamps, stones, anything collectible was collected by Charles Darwin.
His mother died in 1817 at age 52, when he was eight years old. His older sisters took on the role of his upbringing. He did not like school and his father saw this. He was taken out of school when he had matriculated and set up in medical school in Edinburgh to become a physician just like his father and his father before that. But Charles Darwin was not very good at medical school, he couldn’t stand to see anyone in pain. He was a very sensitive man, and he couldn’t stand the sight of blood. Not even a drop of it. His father saw that he was not suited for a medical life and so his father sent him to be a clergyman (priest) in Cambridge. Charles finished his B.A. in 1831 without honours. He returned to Shrewsbury and he had a letter waiting for him. He had been invited to join the expedition of the Beagle. His father strongly objected but Darwin’s uncle convinced Darwin to go. The purpose of the Beagle was to circumnavigate the globe and to produce maps, mainly of South America. Charles Darwin tagged along as the Naturalist of the ship. He spent most of his time trekking on the land and collecting samples of insects and animals. When arriving on the Galapagos Islands, he took many samples of different birds from different parts of the island.
On returning home, his friend told him that the birds he collected where all different varieties of finches, from different parts of the islands. This
made Darwin think about why they were so different yet from the same ancestry. Darwin was finding the key to evolution. He began to think that every living organism came from the same ancestor. This upset his faith in god when he found more and more evidence on evolution and that humans were not descended from Adam and Eve. For 20 years he perfected his theory and gathered evidence and then finally published his book: “On the Origins of Species by means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life”, on the 24th of November 1859. He has published six different editions.
He married his cousin, Emma Wedgewood, on the 29th of January in 1839. He published a great other number of papers and books and biographies. He had ten children, only seven of which reach adulthood. His first child, William, married but had no children. He was a banker in Southampton. He died in 1914. The second child, Anne, died at age ten, it is thought because of tuberculosis. She died in 1851. By then Charles Darwin’s faith had massively decreased and with Annie’s death he no longer believed in god. His third, Mary, died a few weeks after birth in 1842. Henrietta, the fourth child, married and had no children. She died in 1929. Charles and Emma’s fifth child, George, was a mathematician and astronomer and studied the evolution and origins of the solar system. He married and had two sons and two daughters. He died in 1912. The sixth child, Elisabeth, never married and had no children. She died in 1926. The seventh child, Francis, became a botanist specialising in plant physiology. He helped his father with plant experiments and edited and published Darwin’s Autobiography. He married but his wife died while giving birth to their son and he re-married and had on daughter. He was also knighted in 1913 and died in 1925. The eighth child, Leonard, became a soldier and taught at the School of Military Engineering. He married twice but had no children. He died in 1943. Horace, the ninth child, became graduate of Trinity College and Cambridge, and became an engineer and a builder of scientific instruments. He married and had three children. He died in 1928. The last child, Charles, died in 1858 at the age of two.
Darwin died on the 19th of April, 1882 at the age of seventy-three. He was buried in Westminster Abbey.

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