Topic 3 DNA and the genome

Genome

The entire set of genetic material of an organism

Gene

A section of DNA that codes for a particular sequence of amino acids.

DNA is made of

nucleotides

DNA def

A polymer made of nucleotides and contains genetic information

What does a nucleotide contain

sugar-phosphate backbone and nitrogenous base

What holds complementary bases together

weak hydrogen bonds

Chromosome def

Long coiled up molecules of DNA found in nucleus of eukaryotic cells.

How do different bases pair with one another

A-T C-G

Explain the structure of DNA

Two strands coiled together in a double helix

Explain how the fruit practical shows DNA in cells

Firstly mash a fruit such as a strawberries in a beaker containing detergent and salt. The detergent will break down cell and nuclear membranes causing the fruit to release the DNA. Salt causes DNA to stick together. Now filter the mixture in order to remove debris from mixture(insoluble parts of cell). Then add ice cold ethanol to the filtrated mixture. This is to cause the DNA to precipitate(come out the solution) as DNA is not soluble in cold alcohol. Thus the DNA will appear as a stringy white precipitate and can be extracted using a glass rod

advantages of the human gemone project

Can help treat genetic disorders, develop new treatment

How many DNA bases in one amin acid

3