Edexcel: Additional Sciences - Biology: Topic 1 (The building blocks of cells)

Electron microscopes show us that bacterial cells contain two types of DNA. Chromosomal DNA Plasmid DNA Antoni DNA( Chromosomal DNA, Plasmid DNA, Antoni DNA ) is a giant loop small loop Quite long( giant loop, small loop, Quite long ) of DNA containing most containing some containing all containing none( containing most, containing some, containing all, containing none ) of the genetic material. It is not neatly packaged like plant or human chromosomes. Plasmid DNA Chromosomal DNA( Plasmid DNA, Chromosomal DNA ) comes in small loops and carries extra carries less carries an equal amount of( carries extra, carries less, carries an equal amount of ) information

One Gene contains the instructions for One protein Two proteins Three proteins four proteins( One protein, Two proteins, Three proteins, four proteins ). Often several genes work together two genes work together single genes work together eight genes work together( several genes work together, two genes work together, single genes work together, eight genes work together ) to produce what is needed for a single feature. For example, your eye colour shoe size hair colour height( eye colour, shoe size, hair colour, height ) is the result of proteins made by several different genes. So is the size and shape of your nose feet eyes lips( nose, feet, eyes, lips ), and so many other features of your body. Some Genes also carry the instructions for the proteins that control the chemical processes in your body.