Plastic water bottles There are thousands of different kinds of plastic, from shopping bags to Fisher-Price toys to photographic film, CD's, and plumbing pipes. Some plastics, like chewing gum or [...]
Proteins are a type of molecule made mainly out of hydrogen and carbon atoms. They are combinations of smaller molecules called amino acids. The first amino acids probably developed into proteins more than four [...]
A diagram of a sugar molecule found in outer space, from NASA Organic molecules means the kind of molecules that living things are made of - at least, all the [...]
A model of the amino acid molecule glycine (red is oxygen, black is carbon, yellow is hydrogen, and blue is nitrogen atoms) What are amino acids? Amino acids are molecules made [...]
The virus that causes AIDS (greatly magnified) HIV image copyright Russell Knightley Nobody is quite sure whether viruses are living things or not. The first living things may have come [...]
Veins in a leaf About 600 million years ago, the first plant cells evolved to be different from animal cells, and from earlier prokaryote cells, because they had a stiff [...]
Pine trees - A Spruce tree is a type of gymnosperm and conifer Too dry for ferns and moss Near the end of the Carboniferous period, about 300 million years [...]
Squirrel eats pine seeds from a cone Go take a walk outside in the fall and collect pine cones on the ground. How many different kinds of pine cones can [...]
Daffodil with petals and pistil in the middle. Take a long walk around your neighborhood and the park in the late spring and look at all the flowers you see. [...]
Flowering plants: Lavender flowers smell wonderful! Before there were flowers... For millions of years, the Earth was covered with ferns and pine trees and moss and mushrooms, without any flowers, grass, [...]
