Kingdom Plantae

Question 1

What characteristics do all organisms in kingdom plantae have?

Answer 1

• multicellular
• eukaryotic cells
• cellulose cell walls
• feed by photosynthesis using chlorophyll, only some have chloroplasts
• show differentiation

Question 2

Describe the life histories of the kingdom plantae

Answer 2

The life histories involve 2 generations. First a diploid generation occurs, known as a sporophyte, during which spores are formed. this is followed by a haploid generation, known as the gametophyte, during which sex cells (gametes) are produced.
One of the two generations is more conspicuous and occupies a greater portion of the life cycle: this is known as the dominant generation

Question 3

What are Division Bryophyta?

Answer 3

This is the simplest group of land plants and contains two main classes, the liverworts and mosses

Question 4

Why are Division Bryophyta small?

Answer 4

They are poorly adapted to live on land and confined to damp, shady places and seldom reach a significant size

Question 5

What are the consequences of having no true vascular tissue?

Answer 5

They lack xylem and phloem and as a result there is no vascular tissue to offer support. support is due to turgor within cells

Question 6

Why is there no leaves or stems for Division Bryophyta

Answer 6

The so-called leaves of mosses are haploid and are not homologous to true leaves which are diploid

Question 7

Where do Division Bryophyta have cuticle and stomata?

Answer 7

In sporophyte capsules which provides a degree of protection as this part of plant extends above the main plant into the drier air

Question 8

Which generation is dominate in Division Bryophyta

Answer 8

Haploid gametophyte generation is dominant

Question 9

How are the bodies of mosses anchored?

Answer 9

By rhizoids, not roots. Rhizoids are haploid, filamentous outgrowths of the gametophyte

Question 10

Why are mosses limited to areas with water?

Answer 10

Rhizoids do not penetrate soil, so moss is limited to ares with water and ions close to surface of soil

Question 11

How are moss spores distributed/

Answer 11

Mosses produce spores in a capsule at the end of a stalk that lifts the spore producing capsule above the ground. This enables the spores to be dispersed by wind currents

Question 12

What is the advantage to mosses of growing on walls?

Answer 12

Avoid competition from grasses and other plants and avoid damage by trampling.

Question 13

What are division Tracheophyta?

Answer 13

These multicellular plants are the most primitive group to evolve a true vascular system.
Examples of tracheophytes are: Pteridophytes (ferns), Spermatophytes (angiosperms – flowering plants)

Question 14

How are water and nutrients transported in Division Tracheophyta?

Answer 14

The system consists of xylem (for transporting water and mineral ions) and phloem (distributes organic nutrients). Support is by turgor within the cells and the woody xylem vessel and other strengthening elements of the vascular bundles.

Question 15

What is the habitat of ferns?

Answer 15

Dark and damp areas eg under hedgerows

Question 16

What subdivision are ferns?

Answer 16

Subdivision Pteridophytes

Question 17

What are the structures of a fern

Answer 17

Ferns have a single leaf stalk out of which grow the fronds. A frond is a single leaf. Each frond is made up of pinnae, and these are subdivided into pinnules.
If you look frond, you will see small brown dots these are the spore producing structures.

Question 18

How are Tracheophytes adapted to life on land?

Answer 18

• Multicellular plants which are well differentiated
• They have true roots, stems and leaves. Leaves are subdivided into leaflets called pinnae.
• The leaves waxy cuticle is waterproof and reduces the water loss
• They have fine control over their stomata. This allows the stomata to be closed if the plant is subject to water stress.
• The partially lignified vascular system provides mechanical support and transports water and nutrients easily between the roots and leaves. This means the tracheophytes can develop into larger, more complex plants and grow taller and live in drier habitats than the bryophytes.
• There are well developed systems for water and ion distribution (xylem) and for the distribution of organic nutrients (phloem).
• Support is by turgor within cells and by the woody xylem vessels and other strengthening elements of the vascular bundles.
• In many ferns the stem (rhizome) runs horizontally underground with the leaves being the only part that extends above ground
• Ferns disperse spores that germinate in damp conditions - the spores are not highly resistant to desiccation.
• In tracheophytes the life cycle has an alternation of generations in which the diploid sporophyte is the dominant generation, and in which the gametophyte is represented by a prothallus (pteridophytes) or by the contents of developing spores (spermatophytes)

Question 19

What is subdivision Spermatophyta

Answer 19

Flowering plants (angiosperms) which have flowers as reproductive structures and produce seeds instead of spores

Question 20

In what way are subdivision Spermatophyta variable?

Answer 20

They are very variable in form and include small herbaceous plants & large trees. The diversity of flowering plants has resulted in different species being adapted for virtually all the habitats available on Earth. Angiosperms can be highly adapted for anything in between very moist environments i.e. hydrophytes, to extremely dry environments,
ie xerophytes.

Question 21

How are angiosperms adapted?

Answer 21

• Multicellular plants which are well differentiated
• They have true roots, stems and leaves.
• The leaves have a waterproof waxy cuticle that reduces the water loss
• They have fine control over their stomata. This allows the stomata to be closed if the plant is subject to water stress.
• Vascular tissue is highly developed, and the roots are able to penetrate deep into the ground to absorb water and minerals
• Xylem is more extensive and capable of providing much more support than in ferns. Trees are usually over 95% xylem. In older trees most of this wood no longer transports water and has a purely supportive role. This allows trees to reach great heights and obtain more light when growing in woodland.
• Most of the living tissue – phloem and supporting cells, are found in a thin rim around the edge of the stem of angiosperms, and the main water conducting vessels, xylem are also located in the outer rim.
• Seeds have a tough outer coat which provides protection again desiccation. Many seeds can be dispersed in hostile environments, and remain dormant but viable for decades and eventually germinate if the conditions become favourable and sustainable. Seeds are adapted to be dispersed by either wind, insect, animal, bird or by an explosive mechanism.

Question 22

What is double fertilization?

Answer 22

There are 3 male gametes in a pollen tube. The first male nucleus fuses with the egg nucleus forming a diploid zygote. The second fuses with the 2 polar nuclei found in the middle of the embryo sac producing a triploid primary endosperm nucleus. The third is just the pollen tube nucleus