GIGO

The Wonder of Life

Former US president Gerald Ford used to be pilloried for apparently being incapable of walking and chewing gum at the same time, such was his reputation for grace and coordination. The more I learn of the intricacies of cell structure and metabolism, the more amazed I am that any of us are able to master these "skills", let alone anything more complicated.

I remember long afternoons of cell biology classes, peering down microscopes and painstakingly drawing all the different organelles and cell structures that I was supposed to be seeing. Complicated chemical pathways, the intimate dances of DNA and RNA, membrane traffic routing and the mysteries of mitochondria gave me a very healthy respect for the sheer complexity of life.

I have heard it said that if you could translate the coded instructions of the DNA for a single cell into English, you could easily fill a 1,000-volume encyclopdia. It's one of those glib analogies that crop up, but at least it gives you some appreciation for the vast amount of activity going on in just one cell.

Add another 60 trillion or so cells and you've got the right number for a human body. There are some 250 different kinds of cells that make up all the weird and wonderful living organisms on this planet. It seems a small number to account for the incredible diversity of life we encounter, from hawks to hawthorns, from spiders to spider monkeys.

It's hardly surprising that there are still great gaps in our knowledge of what makes living things tick or how it all gets put together. The latter area in particular has been intriguing me over the past nine months. Fuse two special cells together under the right conditions and suddenly your body becomes the site of busy construction, cells differentiating left, right and centre in the trite-but-true "miracle of creation".

It's a process you can feel happening, thanks to our heritage of mammalian placental reproduction. There's a certain fascination in being made aware of the development of a whole new organism sheltered within the confines of your own body. At times, one can envy the marsupials their sensible pouch systems, or the reptiles their independent egg approach. But when you see 4350g (9lb 9oz for any unregenerate Imperialists) of baby boy, you do have to marvel at what a piece of work is Life.

Vicki Hyde is the editor of New Zealand Science Monthly.