The first organisms were made of only one cell, the earliest cell was a prokaryote

prokaryotes surrounded by cell membranes and do not have a nucleus

Both archaea and bacteria are made up of prokaryotic cells

get their nutrients directly from the water they live in

Also need to be able to make copies of themselves storing information in nucleic acids

The first organisms to photosynthesise was cyanobacteria

used to compare the relatedness (genetically similarity) of different species

Heating a solution containing DNA disrupts the hydrogen bonding between the two complementary strands

1. the particular gene sequence is isolated with a gene probe and enzymes

2. the DNA of the two species is heated to 95c to separate the strands

3. the strands are mixed are mixed together and allowed to cool, enabling hybrid DNA to form

4. The strands are reheated to work pit the melting point of the hybrid DNA. The melting point is defined as the temperature at which 50% of the DNA is a single stranded and 50% is double stranded. Essentially the higher the melting point, the more bond between the DNA molecules the more common are the two sequences of DNA

5. the higher the melting point the greater the similarity between the DNA sequences and the more likely it is that they shared a more recent common ancestor

Measures the similarity between the genomes of different species

two complementary single stranded DNA and/or RNA molecules bond together to form a double stranded molecules

important process in various research and clinical lab techniques