Plant Kingdom Flashcards
(155 cards)
Are Blue Green algae a part of the Plant Kingdom?
No, Blue Green algae or cyanobacteria are a part of Kingdom Monera and not the Plant Kingdom.
Which divisions come under Kingdom Plantae?
Algae, Bryophytes, Pteridophytes, Gymnosperms and Angiosperms are the divisions of Kingdom Plantae.
Explain the Artificial Classification of Angiosperms. (6)
- Earliest classification system
- Based on gross morphological characters like habit, color, number and shape of leaves.
- Based on vegetative characters or the structure of the androecium.
- Given by Linnaeus
- Only separated closely related species because they are based on few characteristics.
- Gave equal importance to sexual and vegetative characters but vegetative characters are more easily affected by the environment.
Why is giving equal importance to sexual and vegetative characters not acceptable?
Vegetative characters are more easily influenced by the environment.
Explain the Natural System of Classification. (3)
- Based on natural affinities between organisms.
- Besides external features, importance is given to internal features like ultrastructure, embryology, anatomy and phytochemistry.
- George Bentham and Joseph Dalton Hooker gave the Natural System of Classification of flowering plants.
Who gave the Natural System of Classification of Flowering Plants?
George Bentham and Joseph Dalton Hooker.
Explain the Phylogenetic Classification System. (2)
- Based on the evolutionary relationships between various organisms.
- Believes that two organisms in the same taxa share a common ancestor.
Why do we need information from many sources to resolve difficulties in classification?
Information from many sources becomes more important especially when there is no supporting fossil evidence.
What is Numerical Taxonomy?
- Numerical Taxonomy is based on all observable characteristics.
- Carried out with the help of computers.
- Numbers and codes are assigned to each character and then the data is processed.
- Thus each character is given importance and hundreds of characters are considered.
What is cytotaxonomy?
Taxonomy based on cytological information, chromosome number, structure and behavior.
What is chemotaxonomy?
Based on chemical constituents of plants.
Basic definition of algae.
Algae are chlorophyll bearing, simple thalloid autotrophic and largely aquatic organisms. (Can be found in fresh water, sea water and on other habitats like moist stones, soil and wood.
They can occur in association with fungi (lichens) and animals (on sloth bear).
Colonial form of algae
Volvox
Filamentous forms of algae
Ulothrix and Spirogyra
Massive marine forms of algae
Kelps
Vegetative reproduction in algae
Fragmentation - each fragment develops into a thallus
Asexual reproduction in algae
Formation of spores, most common being zoospores.
Spores are flagellated (motile) and on germination give rise to new plants.
Sexual reproduction in algae
Formation of gametes. 3 types - Isogamous. Anisogamous and Oogamous
Examples of isogamous gametes in algae
Isogamous - same size
ex: Ulothrix - same size and flagellated
Spirogyra: same size and non flagellated
Example of gametes being the same size and flagellated in algae
Ulothrix
Example of gametes being the same size and non flagellated in algae
Spirogyra
Fusion of gametes dissimilar in size example
Anisogamous - Ex: Eudorina
What are oogamous gametes in algae
Gametes are dissimilar in size but fusion occurs between one large static female gamete and a smaller motile male gamete. Eg: Fucus and Volvox
Example of oogamous gametes in algae
ex: Fucus and Volvox