IGCSE Biology 0610: Plant Kingdom Features, Ferns, Monocots and Dicots

A biology class compares a garden spider with a rose bush, and then examines three further plant specimens, W, X and Y, collected on a walk.

Both the spider and the rose bush are made of eukaryotic cells and are multicellular.

Specimen W: reproduces by releasing spores from structures on the underside of its fronds; produces no flowers or seeds. Specimen X: produces flowers; each seed contains one seed leaf (cotyledon); its leaves have parallel veins. Specimen Y: produces flowers; each seed contains two seed leaves (cotyledons); its leaves have a branching network of veins.

(a) State two features of the rose bush's cells that would place it in the plant kingdom rather than the animal kingdom, which the spider's cells do not have. [2]

(b) State the group, within the plant kingdom, to which specimen W belongs. [1]

(d) State the group, within the flowering plants, to which specimen X belongs. [1]

(e) State the group, within the flowering plants, to which specimen Y belongs. [1]

Part (a): Plant kingdom features of the rose bush’s cells

Both organisms are eukaryotic and multicellular, so these features cannot be used to separate them. Instead, the rose bush’s cells have a cellulose cell wall, surrounding the cell membrane, which animal cells such as the spider’s do not have. The rose bush’s cells also contain chloroplasts, containing the pigment chlorophyll, allowing the rose bush to photosynthesise; the spider’s cells contain neither chloroplasts nor chlorophyll. These two features, a cellulose cell wall and chloroplasts, are used to place an organism in the plant kingdom.

Part (b): Specimen W

Specimen W reproduces by releasing spores from its fronds and produces no flowers or seeds. Within the plant kingdom, reproducing by spores rather than by flowers and seeds is the defining feature of the fern group.

Part (c): Why specimen W is not a flowering plant

The flowering plants are defined by producing flowers and seeds as their means of reproduction. Since specimen W instead reproduces using spores released from its fronds, it does not meet this defining feature, and so it is placed with the ferns rather than with the flowering plants.

Part (d): Specimen X

Specimen X produces flowers, so it is a flowering plant, but each of its seeds contains only one seed leaf (cotyledon), and its leaves have parallel veins. One seed leaf and parallel leaf veins are the features of a monocotyledon.

Part (e): Specimen Y

Specimen Y also produces flowers, but each of its seeds contains two seed leaves (cotyledons), and its leaves have a branching (net) pattern of veins. Two seed leaves and branching leaf veins are the features of a dicotyledon.

Final answers

(a) A cellulose cell wall and chloroplasts (containing chlorophyll).
(b) Specimen W: fern
(c) It reproduces using spores rather than flowers and seeds.
(d) Specimen X: monocotyledon
(e) Specimen Y: dicotyledon