Characteristics of Spermatophyte:
1. They are multi-cellular, seed-producing plants including most trees, shrubs, and herbaceous plants.
2. They are vascular plants and have well-developed vascular tissues.
3. They have true roots, leaves and stems.
4. They reproduce sexually and do not need water for reproduction.
5. They are mainly terrestrial green plants.
6. The seed plants are divided into gymnosperms and angiosperms.
Classification of Spermatophyte:
Spermatophytes can be divided into two main classes. These are
1. Gymnosperms have a well-differentiated plant body and vascular tissues.
2. They are seed-bearing plants that do not produce flowers.
3. They have true roots, stems and leaves.
4. The seeds grow exposed on a cone, not enclosed within a fruit. Hence, the term “Gymnosperm”, which is derived from the Greek word, gymno = naked and Sperma = seed, which means naked seed.
5. They bear no fruits.
6. They show alternation of generation with the sporophyte as the gymnosperm plant or dominant generation while the gametophyte is severely reduced.
7. Examples are
i. Palm-like Cycads
ii. Gingkoes – (fan-like leaves)
iii. Gnetophytes (scale-like leaves)
iv. Conifers e.g. pines (needle-like leaves e.g Whistling pine), firs, spruces.
Class Angiospermae (Flowering Plants):
1. They have true roots, stems and leaves hence they are said to have a well-differentiated body.
2. They produce seeds which are enclosed by fruits.
3. Fruits develop from the ovaries of flowers.
4. They have a well-developed vascular system.
5. Sporophytes are dominant with the gametophyte (flower) severely reduced.
6. Angiosperms are grouped into monocotyledons and dicotyledons.
7. Examples include. oil palm tree, maize plant, mango tree etc.
Difference between Gymnosperm and Angiosperm:
|They do not bear flowers.||They are flowering plants.|
|Seeds are naked.||Seeds are enclosed.|
|Seed borne on cones.||Seeds develop from ovules.|
Sub-Classes of Flowering Plants:
Flowering plants are divided into two subclasses;
Monocotyledons are flowering plants with only one cotyledon in their seeds. Most monocots have long narrow leaves e.g. grasses, cereals, palms, and coconut.
Dicotyledons are flowering plants with two cotyledons in their seeds. Their leaves are usually broad with their leaf veins forming a branching network e.g. mango, orange, waterleaf, cowpea, groundnut, Neem tree.
Difference between Monocotyledons & Dicotyledons:
|1.||Embryo||They possess only one cotyledon |
in their seeds.
|They possess two cotyledons |
in their seeds.
|2.||Roots||They have a fibrous root system.||They have a tap root system.|
|3.||Flowers||Floral parts are arranged in threes|
and multiples of threes.
|Floral parts are arranged in |
fours and fives.
|4.||Leaves||Their leaves have parallel venation.||Their leaves have net venation.|
|They do not undergo secondary growth.||They undergo secondary growth.|
|6.||Germination||They exhibit hypogeal germination.|
i.e. the cotyledon is returned below the soil.
|They exhibit epigeal germination. i.e. |
the cotyledons shoot out to the soil surface.
|Vascular bundles are scattered.||Vascular bundles of stem are |
arranged in rings.