o The Frog Blog: June 2009

Friday, 19 June 2009

Summer Holidays

Today is the final day of term and the end of the Academic Year 2008 / 2009. The Frog Blog has been in existence for little over one year, posting over 250 articles on science related topics. We have also been nominated for an Irish Blog Award and been named a Scoilnet Star Site. The Frog Blog has been far more successful than we could have hoped for. We receive over 8,000 hits every month, from Ireland and beyond and our hit stats keep rising. We have received numerous positive comments from teachers and pupils of science from across the globe which really motivate us as educators. We encourage you to continue to read our blog and hope you enjoy our blog as much as we enjoy putting it together. We are now taking a well deserved summer holiday, returning in early September 2010. Next year you can expect much of the same: science facts of the week, daily science news, science history, famous Irish scientists, nature notes, our now famous penguin corner, plenty of frog references and perhaps a new feature or two. We thank you all for reading and look forward to kicking off again in September. Enjoy your summer holidays and see you all again soon.

Thursday, 18 June 2009

Exam Reaction 2009 - Agricultural Science

The Leaving Certificate Agricultural Science exam is often difficult to predict and usually throws a few banana skins in the candidate's direction. This paper was no different, but overall most pupils should be happy. Question 1, the short questions, were very fair and all pupils were able to find at least six they could tackle strongly. The soil question, number 2, was quite straightforward, although the wording of (a), part (i) was a little vague. Other than that, the soil question was a real option for most pupils. Question 3, options 1 and 2, were again fair and pupils should really have no excuses. In particular, option 1 (which assessed Dairy Management) was very fair. Question 4 traditionally assesses knowledge of laboratory and fieldwork methods. This year was no different, although some may have found the choice a little limited. Question 5 assessed cereal and potato production and was fair (although not all pupils opt to study potatoes as their root crop). Question 6 assessed animal classification and physiology and was again straightforward, although some got caught out by the ruminant dental formula (below for reminder). The genetics question, number 7, was again fair but many were caught by the question on embryo transfer. Question 8 was a mixed bag, but overall was fine and question 9, the scientific explanations, were fair but with limited choice. All in all, this paper will not cause major problems for the average pupil but the individual looking for an "A" may not be best pleased.

The Frog Blog would like to put their support behind the introduction of a new Agricultural Science syllabus. The present syllabus is so vague and lacking detail (available by clicking here, if you want a good laugh), that it is a significant challenge to the Ag. Science teacher to provide pupils with the opportunity to tackle the exam properly and truly prepare them for an agricultural career. In comparison, the Biology syllabus is clear and concise. (Click here for view the Biology Syllabus). There is no standardisation between one school and the next and the longer we continue to use an Agricultural Science syllabus that was written before Ireland joined the European Union (Or EEC as it was at the time) the more we discredit this fine subject. Agricultural Science is one of the fastest growing subjects in Ireland and we need to promote it, not demote it. Come on Mr. O'Keeffe, show the public that you can be proactive.

Wednesday, 17 June 2009

Burren Expedition 2009 - Photo Album

Every year, the members of Form V spend a week in the Burren in Co. Clare, carrying out Biology and Geography fieldwork. Below are a series of photos, taken by Mr Ronan Swift, of the Biology group on their adventures. The photos include members of the group partaking in the annual three mountain hike, visiting the Cliffs of Moher and studying the plants and animals of the Burren.

Sir William Crookes

Today, in 1832, the British chemist and physicist William Crookes was born. Discovery of the element thallium is attributed to him, and he also showed that cathode-rays were fast-moving, negatively-charged particles. He invented the Crookes' Radiometer (shown below) in 1875, in which four vanes suspended on a needle in a vacuum with one side black and the other side white, are observed to rotate by the effect of incident light. This verifies that light is indeed a form of energy and can do work. Crookes also identified the first known sample of helium, in 1895. He invented the spinthariscope in 1903 which reveals alpha particles emitted by radium.

He also had a fascination with ghosts and spirits and conducted experiments in his home with mediums. There he reported to have witnessed several unexplained phenomena, including levitation and viewing of "phantom figures". Many of his claims were discredited by his scientific peers although he continued to air his views and had some well known supporters, including Alfred Russell Wallace, the co-developer of the Theory of Evolution.

Tuesday, 16 June 2009

Exam Reaction 2009 - Chemistry

The Leaving Certificate Chemistry exam took place earlier this afternoon. The higher level paper has been described by both teacher and pupils as "fair", with a series of good predictable questions. In Section A many greeted the titration question while in Section B, equilibria was only given half a question and electrochemistry was also assessed. All in all, the exam ticked the right boxes.

More New Amphibian Species Discovered

The Frog Blog reported earlier this year (here and here) on new species of frog that were discovered in Madagascar and Panama respectively. The Frog Blog now hears that more new amphibian species have been discovered near the border of Peru and Ecuador, in the Cordillera del Cóndor, an outlier of the main Andean chain which rises to a maximum elevation of about 2900 metres. Because of its geographical seclusion from the rest of the Andes, the Cordillera is thought to be home to many unique species that have evolved in isolation. Amongst the new species discovered are a bug-eyed salamander (shown above, which we think looks a little like ET), a tiny, endangered poison arrow frog, a colourful, polka-dotted lizard and a number of bizarre-looking crickets. They also found a number of endangered species including Hyalinobatrachium pellucidum, a glass or crystal frog that has translucent skin.

Monday, 15 June 2009

Exam Reaction 2009 - Physics

The reaction to this morning's Leaving Certificate Physics paper was again generally positive. In Section A few problems were experienced with most questions deemed "straightforward", including the experiment questions. In Section B, there were few problems reported again, although some felt the mechanics question was on the "more difficult side". The particle physics question was again deemed very straightforward. All in all, pupils were generally happy with the exam and are confident of decent grades.

Science Fact of the Week 24 - Black Holes

A Black Hole is a region of space in which the gravitational force is so powerful that nothing, including light, can escape its pull.

Black Holes are formed when a large star runs out of fuel and it can no longer support its heavy weight. The pressure from the star's massive layers of hydrogen press down forcing the star to get smaller and smaller and smaller. Eventually the star will get even smaller than an atom. Imagine that for a moment an entire star squashed up into less space than a tiny atom! But by making the star smaller, its gravity becomes much stronger. A black hole's gravity becomes so powerful that everything, including light, that gets too close, gets pulled in. That's right, not even light can escape the grasp of a black hole. The middle of a black hole is called a Singularity. When you get too close to the singularity you will begin to fall into it. When you begin to fall toward it you know you have passed the Black Holes Event Horizon. The Event Horizon is a one-way surface into which objects can fall, but out of which nothing can come.

The Hubble Telescope website has a fantastic video explaining how Black Holes are formed. Click here to visit the site. This is the final Science Fact of the Week for this academic year. The next Science Fact of the Week will return in September!

Saturday, 13 June 2009

Ireland's Birds of Prey - The Long Eared Owl

Long-eared Owls are the most common owl in Ireland, with a scattered range throughout the country. They are found in woods, copses and coniferous plantations adjacent to open grassland where they hunt mice, rats, shrews and voles. They get their name from their long ear tufts, which are located above the facial disc, giving them a cat-like appearance. These are raised when the owl is alarmed or curious but lie flat when the owl is relaxed or flying. They have a handsome mottled brown coloured plumage (feathers) over most of the body and are well camouflaged. The eyes are a fiery orange, encircled by black feathers set into an orange facial disc. The forehead and lores are a mottled grey-white and the bill is black. They are a medium sized owl averaging 35 - 40 cm in length and a maximum of 350g (females are heavier than males).

Long-eared Owls typically lay 3-5 white eggs from late March onwards and these are incubated for 25-30 days. The chicks typically hatch out over a period of 10 to 12 days and fledge at about five weeks. They remain dependent on their parents until about two months old. In Ireland local populations of Long-eared Owls can be threatened by loss of rough grassland, and increased pesticide use which may reduce prey numbers. The felling of conifer plantations during the breeding season should also be avoided. However as a breeding species the Long-eared Owl is generally doing well and is not listed as being of conservation concern. It is estimated that Ireland may hold 1,000 -3,500 pairs of Long-eared Owl.

Friday, 12 June 2009

New Element Added to Periodic Table

Scientists around the world are celebrating the latest entry to the periodic table. It has taken more than a decade since its discovery (or more accurately its production) for element 112, the biggest and heaviest atom yet, to be officially recognized. The heaviest known naturally occurring element is uranium, with an atomic number of 92 (the number of protons in its nucleus). But since 1941, physicists have been synthesising heavier elements by fusing atoms together. Currently, the heaviest named and recognised element is roentgeniuim at position 111, which was officially named in 2004. Element 112 is the first new element in five years, and is yet to be named. Speculation is rife about who or what the new element will be named after. We're suggesting "frogbloggium".

Thursday, 11 June 2009

Exam Reaction 2009 - Science & Biology

The reaction to this morning's science and biology papers has generally been positive. In the Junior Science exam, pupils found most questions quite straightforward, although some had problems with the electricity question in the physics section. The ecology question was received positively also. In the Biology paper, most pupils felt the exam was fair and diverse. Section A was very straightforward, as were the experiments in Section B. The longer questions in Section C were deemed very fair. There was a straightforward ecology question (although some felt that a reading comprehension on foxes would be more at home in an English exam). Respiration and photosynthesis were assessed within question 12 and again proved popular amongst the pupils - as did the straightforward question 10 which included genetics and evolution (which was expected considering the theory is 150 years old this year). Circulation and breathing were assessed in question 13, again with few complaints, while questions 14 and 15 had a good mix of topics from Unit 3. All in all, the paper was fair and most pupils are confident of achieving a good grade. Well done everyone!

Science & Biology Exams Today

Good luck to all pupils sitting their Junior Certificate Science and Leaving Certificate Biology exams today, especially those in St. Columba's. We hope that all your hard work will pay off. Good luck, but you shouldn't need luck!

Wednesday, 10 June 2009

Prehistoric Whale Found in Sweden

The skeleton of a whale that died around 10,000 years ago has been found during work to extend a motorway in the city of Strömstad. The whale bones are now being examined by researchers at the University of Gothenburg who, among other things, want to ascertain whether the find is the mystical “Swedenborg whale”. This whale species is believed to have existed in the North Sea from the period when the inland ice melted until about 8,000 years ago, and subsequently to have died out. Ten collections of bones from the species have been found in the west of Sweden. However, there is speculation that the bones have been mistaken for other species, and that the Swedenborg whale never existed. Below is a picture of what the Swedenborg whale may have looked like. For more information, see a detailed article on the find on Science Daily, by clicking here.

Happy Birthday Biro!

Today, in 1943, the ball point pen was patented by Laslo Biro. He had invented the pen with quick-drying ink in 1938 while Biro was a journalist in Budapest, Hungary, where he was also a sculptor and hypnotist of all things. Biro escaped the Nazis by travelling via Paris to Argentina in 1940. There, Englishman Henry Martin, in Buenos Aires on a mission for the British government, saw the invention and recognized its value for air crews making high altitude navigational calculations. This new type of pen would write blot-free, unaffected by low or changing atmospheric pressure. Martin aquired the rights and began small scale production of ballpoint pens for the RAF. Commerical production under Biro's patents began in 1945 by the Eterpen Co in Buenos Aires.

Tuesday, 9 June 2009

Science Fact of the Week 23 - Tyrannosaurus rex

Tyrannosaurus rex was one of the largest meat-eating dinosaurs that ever lived. Everything about this ferocious predator, from its thick, heavy skull to its 1.2-meter-long jaw, was designed for maximum bone-crushing action. Fossil evidence shows that Tyrannosaurus was about 12 metres long and about 4.6 to 6 metres tall. Its strong thighs and long, powerful tail helped it move quickly, and its massive 1.5-metre-long skull could bore into prey. T. rex's serrated, conical teeth were most likely used to pierce and grip flesh, which it then ripped away with its brawny neck muscles. Its two-fingered forearms could probably seize prey, but they were too short to reach its mouth. Scientists believe this powerful predator could eat up to 230 kilograms of meat in one bite. Fossils of T. rex prey, including Triceratops and Edmontosaurus, suggest T. rex crushed and broke bones as it ate, and broken bones have been found in its dung. Tyrannosaurus rex lived in forested river valleys in North America during the late Cretaceous period. It became extinct about 65 million years ago in the Cretaceous-Tertiary mass extinction.

Wednesday, 3 June 2009

Junior & Leaving Certificates

Best wishes to all pupils, in St. Columba's and all across Ireland, beginning their Junior & Leaving Certificate exams today, initially with English Paper 1. All your hard work and preparation will be rewarded. Good luck!

Good Luck Burren Adventurers

The Frog Blog would like to wish all the Form V pupils heading off to the Burren today a safe, enjoyable and, most importantly, an educational trip. Over the next few days the 35 pupils on the Biology expedition will learn first hand the unique geology, botany (as pictured above), history and ecology of the Burren. The pupils are accompanied by Mr. Peter Jackson, Ms. Karen Hennessy, Dr. Ulrica Riemenschneider and Mr. Ronan Swift and will carry out ecological studies on the rocky seashore, Fanore sand dunes and the limestone pavements. They will also partake in a three mountain hike. We hope that the weather will remain sunny and warm over the next few days and we will post photos of their adventures next week. Good luck and enjoy yourselves!

Tuesday, 2 June 2009

Science Fact of the Week 22 - Structure of Planet Earth

For thousands of years humans have wondered about the Earth beneath their feet. The ancient Greeks and Romans had a vision of Hades, an underworld peopled by the dead and ruled by the god Hades or Pluto. Medieval Christians believed in a fiery underworld ruled by Satan, where evil doers were sent after death for an eternity of torment. In 1864 the French pioneer of science fiction writing, Jules Verne, published Voyage au centre de la Terre, in which German professor, Otto Lidenbrock (or von Hardwigg in English versions), with his nephew Axel and their guide Hans follow a coded message from an ancient Icelandic manuscript and enter the underworld via the Icelandic volcano Snaefellsjökull, and hair-raising adventures ensue, before eventually re-emerging in southern Italy.

Our current understanding of the internal structure of planet Earth is a little more mundane, but none the less interesting for that. A cross-section through Earth would show a concentrically layered structure with an outer, solid, lithosphere consisting of crustal rocks and bits of upper mantle. This floats on a partially molten layer called the aesthenosphere, which itself sits on (generally) solid mantle rocks. At the centre of the Earth is an iron-rich core, divided into a liquid outer core and a solid inner core.

Evidence for the Earth’s structure comes from the refraction, reflection and travel times of earthquake waves as they pass through the interior. Sudden increases in wave velocities at a depth of about 5 km to 70 km mark the Mohorovičić discontinuity, between the crust and mantle. Shock waves produced by US nuclear weapons tests in Nevada helped to pinpoint the position of the Gutenberg discontinuity (2,900 km below surface), which separates the core from the mantle. The Earth’s strong magnetic field also suggests an iron rich core, as does the abundance of iron in meteorites which represent the original building blocks of planet Earth – floating around in space, virtually unchanged for the past 4,600 million years. The strength of the Earth’s force of gravity reflects the size and density of the planet, and modelling this with iron-rich rocks such as peridotite in the mantle gives results identical to those observed. Direct sampling of the mantle is virtually impossible, but occasionally plate tectonic processes throw a bit of mantle rock up onto the surface for us to examine e.g. the Ronda peridotite in Spain.

Part of the crust consists of basaltic rocks forming a layered structure known as ophiolite. This makes up the oceanic crust, and is nowhere older than about 180 million years. As the name implies, it floors the deep oceans of the world. The other part of the crust consists of a mish-mash of igneous, sedimentary and metamorphic rocks, some of which may be almost 4,000 million years old. This is known as continental crust, and forms the world’s landmasses and shallow seas.