16 public questions tagged with this topic.
Cytotaxonomy is based on the study of cytological characters such as chromosome number, structure, and behavior.
Ref: NCERT Class 11 Biology Chapter 3: Plant Kingdom Plant Kingdom - Comparative Studies and Economic Importance
The International Code for Botanical Nomenclature provides agreed principles and criteria for assigning scientific names to plants.
Ref: NCERT Class 11 Biology Chapter 1: The Living World Taxonomical Aids - Herbarium and Botanical Gardens
In plant classification, related classes are assigned to a division. Division corresponds to phylum in animal classification.
Ref: NCERT Class 11 Biology Chapter 1: The Living World Taxonomic Categories - Family Order Class Phylum Kingdom
In plant classification, related classes are assigned to a division. Division corresponds to phylum in animal classification.
Ref: NCERT Class 11 Biology Chapter 1: The Living World Taxonomic Categories - Family Order Class Phylum Kingdom
In plants, classes with a few similar characters are grouped into a division. Division corresponds to phylum in animal classification.
Ref: NCERT Class 11 Biology Chapter 1: The Living World Taxonomic Categories - Family Order Class Phylum Kingdom
In plants, classes with a few similar characters are assigned to the higher category called division. The corresponding category in animals is phylum.
Ref: NCERT Class 11 Biology Chapter 1: The Living World Taxonomic Categories - Family Order Class Phylum Kingdom
In plants, classes with a few similar characters are assigned to the higher category called division, whereas the corresponding category in animals is phylum.
Ref: NCERT Class 11 Biology Chapter 1: The Living World Taxonomic Categories - Family Order Class Phylum Kingdom
Illicium verum producing star-shaped aggregate of follicles rich aromatic anethole belongs to Austrobaileyales family Schisandraceae sensu APG IV expansion including Illiciaceae, not Magnoliales featuring Magnoliaceae Annonaceae, Piperales featuring Piperaceae pepper, or Nymphaeales featuring water lilies Nymphaeaceae. Austrobaileyales distinguished by trimerous spiral flowers, essential oil cells, nodal anatomy trilacunar with three leaf traces, vessels with scalariform perforations primitive, pollen monosulcate. Illicium ovule anatropous bitegmic, endosperm formation cellular, chemistry lignan based shikimic acid pathway precursor for oseltamivir synthesis Tamiflu, confirming systematic position supported by rbcL atpB 18S sequence data independent lines.
Ref: APG IV 2016, Austrobaileyales Schisandraceae Illicium placement star anise order
Members Nymphaeales dominate freshwater aquatic ecosystems worldwide temperate tropical: rhizomatous rooted hydrophyte with floating peltate orbicular leaves possessing extensive aerenchyma lacunae, hydropoten absorbing trichomes, epistomatic stomata only upper surface, long petioles with air canals, insect-pollinated showy flowers with spiral perianth emerging above water beetle pollinated. Species like Nuphar lutea yellow water lily, Nymphaea alba white and giant Victoria amazonica exhibit adaptive modifications for aquatic life such as heterophylly submerged filamentous leaves. Terrestrial shrubs, epiphytic growth or desert succulence xerophytic absent. Order exemplifies early angiosperm ecological diversification into aquatic niches before terrestrial dominance and high diversity.
Ref: NCBI Taxonomy and Campbell Biology, Chapter 30: Nymphaeales aquatic water lily habit
Latex presence abundant in Euphorbiaceae: articulated and non-articulated laticifers produce milky white emulsion containing rubber polyisoprene, diterpene esters phorbol irritant, triterpenoids and starch. Latex exudes after wound sealing laticifer rupture, deterring herbivores and pathogens. Leaves often with paired glands at petiole base stipular, cyathium pseudanthium cup-like involucre in Euphorbia, tricarpellary three-locular ovary schizocarp separating into cocci. Cucurbitaceae sap watery bitter cucurbitacins with tendrils coiling, Rutaceae aromatic oil cavities in leaves, Apiaceae resin ducts but not milky. Consequently milky latex serves as important chemotaxonomic diagnostic, though other families like Apocynaceae also produce latex convergently.
Ref: NCERT Class 11 Biology, Chapter 5: Euphorbiaceae latex laticifers cyathium characteristics
Lamiaceae mint family distinguished vegetatively by quadrangular stem cross-section resulting from decussate growth and prominent collenchyma strands at corners providing mechanical rigidity, opposite decussate leaves often gland-dotted containing volatile essential oils like menthol thymol eugenol synthesized in peltate capitate trichomes. Floral traits include bilabiate zygomorphic corolla, didynamous four stamens two long two short, gynobasic style elevating ovary forming four nutlets mericarps. Apiaceae stems hollow furrowed bearing umbel, Rutaceae terete stems with oil glands but not square, Solanaceae alternate leaves lacking aromatic oils. Square stem therefore reliable field character visible without magnification.
Ref: Campbell Biology, 12th ed., Chapter 30: Lamiaceae square stems aromatic oils diagnostic
Angiosperm Phylogeny Group iteration IV enumerates approximately 416 families within 64 orders, reflecting extensive splitting and merging based on monophyly criteria; e.g., broad Liliaceae sensu lato split into Asparagales families, Scrophulariaceae divided into Plantaginaceae Orobanchaceae, Capparaceae segregated. Numbers fluctuate between references but current consensus cites 416, encompassing about 13,164 genera and roughly 295,000 accepted species worldwide. Earlier Cronquist listed 321 families, estimates 120 correspond to fern families, 250 underestimate angiosperm diversity, 600 inflate due to retaining synonyms and polyphyletic groups. APG figure thus most authoritative contemporary reference for teaching university level.
Ref: APG IV System 2016, 64 orders 416 families angiosperm count molecular system
