Friday 19 August 2011

Make some DNA earrings

Yet another busy week of assignments but I have a new project to post!  Mainly because it's a two for the price of one- it's modidfied from an assignment/ student worksheet that I am making.  Today's project is to make a pair of DNA earrings (or a DNA key chain or window dangle etc).  But first, allow the science geek in me to give you a quick run through on the wonders of deoxyribonucleic acid, better known as DNA (because saying deoxyribonucleic acid too fast is likely to cause tongue dislocations in non-professionals like myself).

DNA is the 'building block of life'.  Nearly every cell in our bodies contains a nucleus- while everyone knows red blood cells don't have nuclei, (plural of nucleus), did you know that mature lens fiber cells in your eye also don't have nuclei?  I didn't before writing this.  Back in the distant past when your parents were doing things you don't want to think about, each parent contributed half of their genetic material to form you.  The exact nature of which I won't go into here- if you are interested in how a cell divides to sort a full human's complement of DNA into half a complement, then go read up on meiosis.  And if you want to read about how those two halves of DNA meet, then there are large portions of the internet dedicated to that sort of thing, so I won't go into it here!

Inside your nuclei you have 23 pairs of chromosomes- 22 autosomes and two sex chromosomes (XX if you are a girl, XY if you are a boy generally).  Each chromosome is made up of a really, really, really, really tightly wrapped length of a single piece of DNA.  The picture below (that I got from this website that goes into a bit more detail than I will here if you are interested in reading more) isn't too bad at showing how it works.  A single piece of DNA (that looks like a twisted ladder), the strand is wrapped around proteins called histones.  These histones are then twisted in turn to form a slightly thicker rope of DNA which is then wrapped further until you end up with a chromosome.



DNA is a polymer, which is a fancy way of saying it is made up of lots of individual units joined together.
These individual units are called nucleotides.  Each nucleotide is made of three parts, a sugar (called deoxyribose), a phosphate group and a nitrogen base.  The nucleotides join together with the sugar group of one joining to the phosphate group of another and so on.  These are the two handrails of the DNA ladder, or more commonly referred to as the sugar phosphate backbone.  A DNA molecule is made of two strands of nuclotide polymers that are joined in the middle at the nitrogen bases- the rungs of the ladder.

There are four different nucleotides found in DNA and these four nucleotides are common to all known life on earth: adenine, guanine, thymine and cytosine.  Adenine and thymine will always pair together in a DNA molecule and guanine and cytosine will always pair together.  The jury is out as to whether E.T. will have the same bases or not- it largely depends on if you believe that the system developed here on earth, which would mean that E.T. would probably have a totally different system, or if life actually came to earth from elsewhere in the universe on an asteroid or comet, in which case who knows.  Or it depends on what sort of Sci-fi you like to read or watch- Star Trek yes, something else possibly not!

OK, that's enough of me boring you for now, lets get on with making our pretty shiny things.  First off the material list.  You will need:
  • Some fine wire (28 or 32 gauge (I have 26 in the photo but it ended up being too thick- I ended up using 32 for mine)
  • Seed beads (two colours, two of each colour for every rung of the DNA)
  • Bugle beads (four colours- one for each nitrogen base.  Remember, to be accurate your adenine and thymine will always pair together and your guanine and cytosine will always pair together so bear that in mind with your colour choices)
  • Wire cutters (or trashed scissors)
  • Earring hooks or keychain hooks or fishing line depending on the final function)
  • A toothpick or a paper clip
STEP 1
Work out how many beads you will need of each colour and type to make a DNA molecule.  The instructions below are for a piece 12 nucleotides long which will produce a nice twist.  Use a longer wire and more beads if you want to make something longer.  You will also need a 90 cm length of fine wire.
Sugar
Phosphate
Nitrogen bases     - adenine
    - guanine
    - thymine
    - cytosine

STEP 1
Take a 90 cm length of wire and find the middle point.  Thread onto the wire two bases (long skinny beads), a sugar and a phosphate and move them to the middle of the wire.


STEP2
Now add a sugar and the next base onto each end of the wire.


STEP 3
Thread each end of the wire into the base and sugar (in order) on the other side of the molecule to form a circle.  Gently pull on each end of the wire until the beads are snuggly against each other.

STEP 4
Add a phosphate, a sugar and the next base pair to both ends of the wire.

STEP 5
Thread the ends of the wires through the base and the sugar on the opposite strand as you did in step 3.  Gently pull on wires until beads are snuggly against each other.

STEP 6
Repeat step 4 and 5 until your DNA ladder is 12 bases long.  On the last base leave a gap in the wires between the two nucleotide bases. 

STEP 7
Use something thin like a toothpick, straightened paperclip or the tip of a pencil to twist the wire around twice.  This makes a loop that you can hang an earring hook or a keychain loop on.

STEP 8
Take the ends of the wires and thread them down through the phosphate beads to the bottom.  This strengthens your DNA molecule. 

STEP 9
Trim the ends of the wire close to your DNA ladder.



STEP 9
Give your DNA molecule a gentle anticlockwise twist and attach an earring hook, key chain ring or tie it to some fishing line if you wish.

Isn't that sweet?  These instructions are rewritten from here.  I'll spare you the educational questions I'll adding to my assignment!  But fun factoid- human chromosomes are from about 50 Mbp (that's 50,000,000 base pairs) to 250 Mbp in length.  The molecule above is 12 base pairs long.  I'll let you figure out how long and how many beads you'd need to make one of these babies to scale!

Monday 8 August 2011

Snowflake Peacock blanket

Snowflake Peacock finished! by Kelshandra
Snowflake Peacock finished!, a photo by Kelshandra on Flickr.
Another old project since I'm too much caught up in assignments to make anything right now. This is the Snowflake Peacock lace shawl/blanket (it depends on what thickness of yarn you use).  I used Patons Australia Big Baby 3ply wool, both because it is lovely and soft and because I wasn't sure how much I would need and it's about the only commercial type of yarn that is readily available here in that sort of weight.

The pattern is another free one!  Snowflake Peacock (link is to yahoo group- membership in group required for access to this and other patterns) was designed by Mmario who has designed many lovely lace patterns (mostly round), many inspired by fantasy series (such as the Pern series, by Anne McCaffrey and the Valdemar series of books by Mercedes Lackey- both old favourites of mine).

I love knitting lace- the only downside of round shawls is that I don't really wear shawls (I'd love too, I just don't know how I could pull it off) and round shawls need to be folded to wear.  The other downside is that knitting in the round means the rows get really long the more you do which can get monotonous.  Particularly when you get to the repeated rows of the long part of the feathers in the third rim of the pattern.  On the plus side though, knitting in the round means you don't need to do purl rows (I don't know why but I prefer knit rows to purl).

Next bigish project is about 3/4 done and still on the needles (it's a vest- I'm venturing into the dangerous world of clothing again) but after that I think I might go for another lace project.  It's so pretty, after all...  Any suggestions would be welcome!

Friday 5 August 2011

Summerflies- knitted lace

I've been at uni all week so my crafting output has decreased.  I am working on a stumpwork embroidery piece but I've a few flowers left to do before finishing it so instead here's a post showing off something I made earlier.

Summerflies finshed and blockedCloser view of Summerflies
 The pattern is called Summerflies and is a free pattern produced by Holly and Ella Knits.  It is a fabulously well written pattern and the different types of lace in the bands mean you don't get bored knitting massive swaiths of the same pattern.  It also knits up incredibly fast- I made this in just 4 days!- which makes it a great pattern if you are looking for a great gift pattern.  I give it 5 stars and a virtual chocolate brownie.

The wool I bought on holiday in Scotland.  I highly recommend buying wool when on holiday if you are a knitter or crocheter- you have the double fun of wool shopping with holiday souvenir shopping.  And when you get home and make it up you get to remember your holiday as you work and whenever you look at your finished project.  The wool was North Ronaldsay Yarn, in the colour Skye Marble that I bought in a little shop on the Isle of Skye.  It's a gently mottled green sort of colour that the photos don't really do justice.  Only grumble about the wool is that it's a little itchy, not a great thing for a scarf.

The only issue I had making this is that it's not QUITE long enough for my tastes.  I had to cut the number of rows down a bit which meant that ideally it would be about 5-10 cm longer from tip to tip I estimate.  It was a good thing I did, however, as I finished it with only a 20 cm length from the skein- it wasn't as if I could pop back over to Scotland to get more!