Download IGCSE Biology Chapter 2 ANSWERS 1. a) i Fungi, ii Protoctists, iii

IGCSE Biology
Chapter 2
ANSWERS
1. a) i Fungi, ii Protoctists, iii Plants, vi Bacteria
b) Euglena is difficult to classify as a plant or animal because it has features of both types of
organism. It has a cell wall and chloroplasts and is therefore photosynthetic like a plant, but it
is motile like an animal because of its flagellum. It is included in the Protoctists because this
group contains single-celled eukaryotes that are otherwise difficult to classify, and algae
because, although they are multicellular, they consist of one type of tissue.
2. a)
RNA or DNA
also see Figure 2.13 p 21
Protein coat
b) A virus is not living. It does not feed, excrete, move on its own, respire, or reproduce
without the machinery of the host cell.
c) All viruses are parasites because in order to reproduce they must invade a cell (i.e. a host).
3. a) An invertebrate is an animal with no backbone.
b) Hyphae are the strands that make up the body (mycelium) of a fungus.
c) Saprophitic organisms feed on dead material by secreting digestive enzymes and then
absorbing the products. They include fungi and bacteria and we usually refer to them as the
decomposers.