If they have a carbon atom in them then they’re complex organic molecules, so things like very simple alcohols like methanol or ethanol, like what you would drink, are complex organic molecules. Here’s Professor McClure again, explaining more to BBC World Service’s, Science in Action. Ice is not a biomolecule, but when it mixes with carbon, the atoms in ice molecules change to produce complex molecules – and that’s when interesting things start to happen. This resulted in the complex molecules needed for life on Earth.Įxactly how this happened is not known, but it involves biomolecules, molecules like DNA which are found in living things. It’s possible that when comets hit Earth billions of years ago, elements in the ice were scattered and struck by lightning – a bright flash of light produced by electricity moving in the atmosphere. Professor McClure thinks these missing elements were brought to Earth in comets - large bright balls of dirt and ice which travel around the Sun in outer space. There's sort of these two alternatives for how you could have had life arise on Earth, and one is that the very basic building blocks, like water, and methane, and CO2 – like, those molecules were definitely brought to Earth by ices in comets, and maybe once they were on Earth, then they reacted with either geothermal heat or some kind of lightning strike to form more complex molecules.Įarth’s primordial soup lacked the building blocks of life – a phrase describing the most basic biological and chemical units needed to support living things, elements like oxygen and carbon. Here she explains to BBC World Service programme, Science in Action, one theory linking ice to the beginnings of life on Earth. Astronomer, Professor Melissa McClure, worked with the Nasa scientists who found ice on Europa, one of Jupiter’s moons. We’ll find out or check if you’re right later in the programme. We know ice is frozen water, but do you know the chemical symbol for water? Is it: So how did we jump from the primordial soup to the first living plants, animals, and eventually humans? And how does ice fit into the story? That’s what we’ll be finding out in this programme, and as usual, we’ll be learning some useful new vocabulary as well.īut first I have a question for you, Neil. It had the potential for life to develop, but something was missing. Billions of years ago, long before the dinosaurs, animals or even plants existed, the Earth had a watery environment of oxygen-free gases and chemicals known as the primordial soup. Yes, in an exciting discovery, the James Webb Space Telescope recently detected the coldest ices ever in outer space, something Nasa scientists think could explain the origins of life on Earth.įor years scientists have debated how life started on our planet. But there’s much more to ice than skiing holidays and cold drinks. Have you ever made a snowman or enjoyed a cold drink on a hot summer’s day? Slippery in winter and cooling in summer, ice is made when water gets so cold it freezes. This is 6 Minute English from BBC Learning English. Note: This is not a word-for-word transcript. Series of chemical reactions in which one change causes another, which in turn, causes another TRANSCRIPT Relating to living plants and animals food grown without the use of artificial chemicals Large object made of dirt and ice travelling around the sun with a bright, burning tailįlash of bright light produced by electricity moving in the atmosphere Most basic biological and chemical units capable of supporting living plants and animals VocabularyĮnvironment on Earth before there were any plants or animals, and which formed the conditions for life Listen to the programme to find out the answer. We know ice is frozen water, but do you know the chemical symbol for water? Sam and Neil talk about science and teach you related vocabulary. The James Webb Space Telescope recently detected the coldest ices ever in outer space, something Nasa scientists think could explain the origins of life on Earth. Climate change: Are there too many people?.
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