Each description below is of a different group of living organisms or of a pathogen.
(a) Multicellular; cell walls made of chitin; feed by secreting digestive enzymes onto food and absorbing the products; store carbohydrate as glycogen. Name the group. [1]
(b) Single-celled; no nucleus; have plasmids and a cell wall. Name the group. [1]
(c) Not made of cells; a protein coat around a strand of DNA or RNA; can only reproduce inside living cells. Name this type of pathogen. [1]
- (a) fungi; accept named multicellular example e.g. Mucor / mould; reject plants; do not accept yeast (single-celled)(1)
- (b) bacteria / prokaryotes; accept named example e.g. Lactobacillus(1)
- (c) virus(es); accept named example e.g. HIV / influenza virus / tobacco mosaic virus(1)
- Answer: (a) fungi (b) bacteria (c) virus
- Examiner tip: Chitin cell walls and glycogen storage are the fungus give-aways — students who write 'plant' because of the cell wall lose the mark.