- It includes higher plants that bear flowers and seeds. Seeds are the result of the reproductive process.
- They contain an embryo along with the stored food, which serves for the initial growth of the embryo during germination.
- The plant body is sporophytic and differentiated into root, stem and leaves.
- An embryo develops from a fertilized egg.
Phanerogams are further classified as gymnosperms and angiosperms.
a. Gymnosperms:
- Seeds are not formed inside a fruit. They are naked.
- They do not produce flowers.
- Xylem does not have vessels and the phloem has no companion cells and sieve tubes.
- These plants have vascular tissues which help in the transportation of nutrients and water.
- They are not differentiated into ovary, style and stigma.
- They are pollinated directly by the wind as the stigma is absent.
b. Angiosperms:
- Angiosperms are highly evolved plants and they produce seeds that are enclosed within the fruit.
- All plants have flowers at some stage in their life. The flowers are the reproductive organs for the plant, providing them with a means of exchanging genetic information.
- They are differentiated into roots, stems and leaves.
- The vascular system has true vessels in the xylem and companion cells in the phloem.
- Plant embryos in seeds have structures, called cotyledons.
On the basis of number of Cotyledons,the angiosperms are divided into two groups:
Dicotyledons and Monocotyledons.
Dicotyledons:
- The seeds of these plants have two cotyledons.
- They contain tap roots , instead of adventitious roots.
- The leaves depict a reticulate venation.
- The flowers are tetramerous or pentamerous and the vascular bundles are organized in rings.
- For example: grapes, sunflower, tomatoes, etc.
Monocotyledons:
- The seeds have a single cotyledon.
- The leaves are simples and the veins are parallel.
- This group contains adventitious roots.
- Each floral whorl has three members.
- It has closed vascular bundles and large in number.
- For Example: banana, sugarcane, lilies, etc.
