This weeks Science Saturday is all about DNA, specifically the inner workings specific to womens DNA (who have two X chromosomes).
Men have both an X and a Y chromosome, but women have two X chromosomes. But this inevitably means that one of the two X chromosomes needs to be “silenced” or turned off. This is done by way of a molecular battle within a cell and one X chromosome is turned off whilst the other remains fully functional.
What’s interesting is the fact that the X chromosome that wins is completely random. In some cells Dad’s X chromosome wins, in other cells Mum’s X chromosome wins. This means that the 100 cell embryo (the point in a child’s development that the X chromosomes are turned off or kept on) means it has a mixture of both Mums and Dads active X chromosomes, and as the cells divide, they maintain the particular active X chromosome they started off with. And this continues on into adulthood.
So if you could look at a womans skin and see which particular X chromosome has been inactivated, you’d see a kind of stripey pattern, which essentially shows the growth and migration of all the first 100 cells when the embryo was only four days old.
It’s been a while since I posted a Science Saturday article, but what better way to re-start the series than with a bang. And have I got something really really good to start us off with.
Filmmaker Cristóbal Vila illustrates the mathematical principles that underpin life and the essence of Nature in this short animation inspired by numbers, geometry, and the natural world. He explains the theory behind each sequence on his website.
The video starts off with an explanation behind the Fibonacci sequence, which is the principle behind the shape of shells, in this case a Nautilus. Vila readily admits to taking “artistic license” with the relationship between the golden ratio and the structure of the nautilus.
The video then goes on to explain about the Golden Rule or Divine Proportion and the interaction between it and the irrational number, Phi, often written as φ (and not to be confused with Pi, better known as π.) Phi plays a major role in the arrangement of sunflowers seeds, flower petals and even in shaping the eyes of insects and the meanderings of rivers for source to mouth. There are lots written about the golden ratio in nature and if you’re interested in learning more, then take a look at this essay by Samuel Arbesman.
Hope you enjoyed learning about the mathematics behind Nature provides all around us every day, and a special thanks to my friend Amber who shared this with me.
Kiev, capital of Ukraine, and home to approximately three million residents, is trying to deal with one of the worst winters in decades. With roads and rail completely covered with around two metres of snow, the army have been called in to help stranded motorists. Meanwhile over six hundred towns and villages across Ukraine are reportedly without power.
A city in which I have lived in and love has come to a complete standstill with shops and services such as hospitals and schools barely able to cope or closed completely. The government has issued advisories to avoid any unnecessary travel and have called upon the armed forces to help clear the snow.
In the meantime, Kievites are making the most of the snow and have boned up on their snowboarding and snowman building skills.
With the thaw about to set in this weekend, and the hopeful return of normalcy that brings with it gridlock, traffic-jams, late trains and school runs, I though it might be fun to reminisce a little on the fun that snow brings. Especially when that fun is at someone else’s expense 🙂
Have you ever dreamed of scaling Mount Everest? Well now you can, without even leaving the comfort of your living room!
This amazing website is a 2 BILLION pixel photo of Mount Everest. It is so detailed that you can zoom in on the mountain slopes and actually see people attempting to summit Everest.
To give you a sense of scale, if you look closely at the bottom of the photo, you can just make out some coloured dots. If you zoom in you can see those colours are the tent city that makes up Everest’s Base Camp….it’s just mind boggling.
The 477 individual images that make up the gigapixel image of the Khumbu glacier were captured by David Breashears during the spring of 2012, from the Pumori viewpoint near Mount Everest and shows the summit of Everest in amazing detail and the nearby peaks of the Changtse and Lohtse mountains. The images are so crisp, you can even attempt to summit the worlds highest peak yourself, without the need of those pesky oxygen bottles and finger numbing frostbite 🙂
Now, where are my mountain boots and my cup of tea?
54 year old Briton, Simon Beck has spent up to ten hours a day tramping around in snow covered hills around Les Arcsski resort in France, creating breathtaking masterpieces to be enjoyed and admired by everyone who whizzes overhead on their cable car or ski lift.
The 54 year old engineer creates these huge geometric forms, some of which are the size of 6 football fields using special snow shoes.
This art form started out as an exercise for Simon. He could not run because his feet gave him problems. Simon first needs to sketch out the length and diameter of the snow circles. He calls his method of work “Reverse Orienting”. But the durability of his work depends on the weather. Nevertheless, these are perfect sights for cable car riders.