State the property of stem cells that makes them useful in medical treatment.

Explain how multicellular organisms develop specialized tissues.

Outline some of the outcomes of the sequencing of the human genome.

has the ability to differentiate (into specialized tissue)

only some genes are expressed in each cell type/tissue;
tissues therefore develop differently/become differentiated;
example of differentiated cell and the function of tissues;

knowledge of location of human genes / position of human genes on chromosomes;
knowledge of number of genes/interaction of genes / understanding the mechanism of mutations;
evolutionary relationships between humans and other animals;
discovery of proteins / understanding protein function / detection of genetic disease;
leads to the development of medical treatment/enhanced research techniques;
knowledge of the base sequence of genes/study of variation within genome;

Candidates either seemed very clear that differentiation was the process that produced specialized tissue or not aware of it at all.

Again, candidates found it difficult to explain how specialized tissue develops.  The best answers explained how cells used genes selectively and gave specific examples of specialized tissue and their functions.

Many candidates confused the human genome project with karyotyping of individuals. However most candidates gained marks by mentioning that the project had been valuable in increasing our knowledge of and ability to treat diseases of genetic origin.