Essential Idea:

Every living organism inherits a blueprint for life from its parents

Skills:

Use of a database to determine differences in the base sequence of a gene in two species

Nature of science

Developments in scientific research follow improvements in technology—gene sequencers are used for the sequencing of genes. [linked to 3.1.U7, 3.1.A1, 3.1.A2, 3.1.S1]

International-mindedness:

Sequencing of the human genome shows that all humans share the vast majority of their base sequences but also that there are many single nucleotide polymorphisms that contribute to human diversity.

Theory of knowledge:

• There is a link between sickle cell anemia and prevalence of malaria. How can we know whether there is a causal link in such cases or simply a correlation?
• Discovery of a correlation in Science is not used as evidence by itself. More commonly a correlation is used to formulate a hypothesis. The hypothesis is then tested to see if an underlying empirical relationship exists, e.g. is the persistence of sickle cell anemia caused by the presence of the malarial parasite.