|Plant Cell Model|
IntroductionEven though it is pretty easy to determine what is living and what is not, it is important for students to learn what the criteria for life is:
- All living things have DNA.
- All living things have a method by which they take energy from their environment and convert it into energy to support their life.
- All living things can sense changes in their surrounds and respond to them.
- All living things reproduce.
DNA and Life: All living things have DNA.
DNA is a molecule. A really big molecule...millions of atoms linked together. It stores an incredible amount of information.
The Structure of DNA
The important things you want your students to learn about the structure of DNA is that it is a double helix formed from the backbone composed of two long strands of atoms linked together. These strands have units, called nucleotides (adenine, thymine, cytosine and guanine) attached to them. These four nucleotide types form together in a specific way...adenine only links with thymine and cytosine only links to guanine. So, if you know one part of a pair of nucleotides, you also can determine the other part of the pair.
Building a Model of DNA
|Building a Model of DNA, 3/30/09|