Kingdom Plantae

Question 1

Structure Plants

Answer 1

Multicellular, composed of eukaryotic cells connected by planetesimals through cellulose walls

Question 2

How is Kingdom Plantae subdivided

Answer 2

Into phyla according to presence or absence of specialised conducting tissue (vascular tissue) and whether spores or seeds are the means of reproduction and dispersal

Question 3

Mosses

Answer 3

Not differentiated into true leaves, stems or routes

Analogous structures - leaf-like
-may consist of single layer of cells

Restricted to moist habitats - form ground layer in many ecosystems

Question 4

Rhizoids for Anchorage in Moss

Answer 4

Benefits: can colonise bare rock surfaces - pioneer

Restriction: distribution limited to areas with water and ions close to surface - dont penetrate soil deeply

Question 5

Absence of Cuticle and Stomata in Moss

Answer 5

Benefit: water and ions obtained directly from damp environment across cell walls of all tissues

Restriction: restricted to moist habitats - though can survive periods of dormancy in a dry state

Question 6

Absence of Vascular Tissue Moss

Answer 6

Benefit: Specialised conduction tissue not essential (water n ions absorbed by all cells)

Restriction: only few cm in height, support is turgor in cells of the moss

Question 7

Spores single-celled haploid reproductive structures in Moss

Answer 7

Benefit: Dispersal of moss - spores possess a tough wall, enabling them to disperse in air w/o drying out

Restriction: spores germinate in moist conditions only

Question 8

Key features of Ferns

Answer 8

•Stem is rhizome with leaves protecting upwards

•leaves possess waterproof cuticle stomata so transpirational water loss reduced

•roots penetrate soil for anchorage and absorption of H2O and ions

•Vascular Tissues present w/ xylem to conduct water and ions from roots - distribute PS products

•support by turgor cells - additional support provided by lignified xylem cells in vascular tissue

•leaves possess numerous spore-producing bodies providing huge reproductive capacity

•spores have tough outer wall - require water for germination

Question 9

Flowering Plants

Answer 9

Angiosperms

Have leaves, stems and routes and flowers - seeds may prod

Possess vascular tissue xylem vessels for efficient conduction of water and ions - extra xylem laid down annually to form wood

Woody shrubs and trees more competitive in raising their leaves even higher in canopy

Dominant plants on Earth

Question 10

Leaves of Flowering Plants

Answer 10

Covered in waxy cuticle and possess stomata

Some species that live in dry habitats have extra features
-xerophytes have adaptions such as rolled leaves and sunken stomata

All flowering plants produce seeds with a tough outer coat providing ability to withstand desiccation though requiring water for termination

Question 11

Seeds vs Spores

Answer 11

Seeds better agents of dispersal

Contain food store for termination of the seedlings and a tougher coat better adapted to withstanding desiccation