Plantae - The kingdom of multicellular, photoautotrophic, eukaryotic organism.
The important characteristics of plantae are-
1. Kingdom plantae includes eukaryotic organism.
2. The organisms are multi cellular except for some lower ones.
3. They are generally autotrophic, photosynthetic. Only a few forms have adopted heterotrophic nutrition.
4. Presence of cell wall which is made up of cellulose.
5. Cell contains chloroplasts, nucleus, mitochondria, golgibody etc.
6. Presence of different pigments like green (chlorophyll), fucoxanthine (brown), phycoerithrin (red) as present in different different plants.
7. A central vacuole is usually present.
8. Locomotion is absent except in some lower category (volvox, chlamydomonus etc.).
9. Body form is irregular.
10. Growth can be observed through entire life.
11. Structural differentiation can be seen except in some lower animals.
12. Higher forms have well defined growing forms in meristem.
13. Food is reserved as starch and fat.
14. Plants are the only organism to provide oxygen to the environment.
15. Plants are the primary producer for all living organism(terrestrial and aquatic).
16. Plants are the only living organisms to trap sunlight naturally from sun (which is the only source of energy on Earth).
17. Reproduction in plants are vegetative, asexuals and sexual.
18. Due to absence of well developed nervous system, plants response to stimuli are comparatively poor.
19. Cell division occurs by formation of cell plate (accumulation of phragmoplast).
20. Plants kingdom can be divided into different classes:
I. Thallophyta: It includes all the algae (green, brown, red,colourless). Thallophyta- are autotrophic in nature as they can make their own food. They contains different pigments like green (chlorophylls) , fucoxanthine (brown), phycoerithrin (red). Their body cannot be divided into stem, root or leaves. Thus they are called thalophyte. Algae can be filamentous, colonial or unicellular. E.g Spirogyra, volvox, Oedogonium, chlamydomonus etc.
II. Bryophyte: Plants belonging to this group have plant body that consists of rhizoid (false root like structure) and leaf-like structure. They contain chlorophyll and are autotrophs. E.g. Mosses ,liver worts.
III. Pteridophyte: Plants of this group contains true plant body that consists of distinguished root, stem and leaves. Leaves are made up of leaflets. Thy are nonflowering plants. So they contain spores on the downward side of leaflets. Which burst into the air and carried away to different places and formed new plants. The young leaves which are remain fold in young stage are called sercinate vernition. E.g. include all fern.
IV: Gymnosperms: The plants belong to this category bear naked seeds as the seeds are not enclosed in fruits. They may be either shrubs or trees. They bear both male and female flowers which carried by winds as they have wings. This two types of flowers are called cycads and conifers. E.g. Cycads, pine, for etc.
V: Angiosperms: It includes all flowering plants. Plants belonging to the group have highly developed plant body, that can be differentiated into root, stem, leaves, flowers and fruits.The seeds are enclosed in a fruit. Angiosperms can be divided into following-
Monocots - Plants of this group have- seed with one cotyledon , parallel venation. Root system is fibrous. E.g. maize, rice, grass etc.
Dicots - The plants belonging to this group bear seeds with two cotyledons, the leaves have reticulate venation, tap root system. E.g. pea, potato, apple.
Question and answer on Kingdom Plantae:
What is stele?
It is a column containing vascular tissues which is surrounded by pericycle and separated from ground tissue by endodermis.