NEET Biology: Comparative Study of Angiosperm Families

Comprehensive vocabulary flashcards covering the vegetative characters, floral structures, fruits, seeds, floral formulae, and economic examples of the angiosperm families Fabaceae, Brassicaceae, Malvaceae, Asteraceae, and Poaceae.

Fabaceae

A dicot family (also known as Leguminosae, Papilionoideae, or the Pea family) characterized by root nodules with nitrogen-fixing bacteria, pulvinate leaf bases, papilionaceous corolla, diadelphous stamens, marginal placentation, and legume or pod fruits.

Brassicaceae

A dicot family (Cruciferae or Mustard family) characterized by tetradynamous stamens, cruciform corolla, a bicarpellary ovary with a replum (false septum), parietal placentation, and siliqua or silicula fruits.

Malvaceae

A dicot family (Mallow or Cotton family) featuring stellate hairs, mucilage sacs, an epicalyx, monadelphous stamens forming a staminal tube, monothecous reniform anthers, axile placentation, and loculicidal capsule fruits.

Asteraceae

The largest dicot family (Compositae or Sunflower family), featuring head (capitulum) inflorescences with ray and disc florets, syngenesious stamens, pappus-modified calyx, basal placentation, and cypsela fruits.

Poaceae

A monocot family (Gramineae or Grass family) characterized by spikelet inflorescences, parallel venation, perianth reduced to lodicules, versatile anthers, feathery stigmas, basal placentation, and caryopsis (grain) fruits.

Pulvinate Leaf Base

A swollen leaf base characteristic of the vegetative morphology in the family Fabaceae.

Stellate Hairs

Star-shaped trichomes present on the stems and leaves of plants belonging to the family Malvaceae.

Epicalyx

An outer whorl or involucre of 3 to 8 bracteoles positioned just beneath the calyx, characteristic of Malvaceae flowers.

Vexillary Aestivation

A papilionaceous petal arrangement in Fabaceae consisting of 5 petals: 1 large posterior standard (vexillum), 2 lateral wings (alae), and 2 fused anterior petals forming a keel (carina).

Cruciform Corolla

A cross-shaped petal arrangement consisting of 4 polypetalous petals with valvate aestivation, characteristic of Brassicaceae.

Diadelphous Stamens

An androecium condition where stamens are united into two bundles, typically exhibiting a $[(9)+1]$ arrangement in Fabaceae.

Tetradynamous Condition

An androecium arrangement of 6 stamens comprising 2 outer short stamens and 4 inner long stamens, characteristic of Brassicaceae.

Monadelphous Stamens

An androecium arrangement where an indefinite number of stamens have their filaments fused into a single staminal tube that surrounds the style, found in Malvaceae.

Syngenesious Stamens

Stamens whose anthers are fused into a cylinder or ring surrounding the style while the filaments remain free, characteristic of disc florets in Asteraceae.

Versatile Anther

An anther attached at a single point to the slender filament tip so that it moves freely in the wind, characteristic of Poaceae.

Replum

A false septum that develops in the bicarpellary ovary of Brassicaceae, transforming an initially unilocular ovary into a bilocular one.

Pappus

A persistent, hair-like modified calyx found in Asteraceae florets that aids in fruit dispersal by wind via a parachute mechanism.

Lodicules

Two or three minute scale-like structures representing the reduced perianth (modified tepals) in Poaceae flowers.

Siliqua

A dry dehiscent fruit type characteristic of Brassicaceae, developing from a bicarpellary syncarpous ovary containing a replum.

Cypsela

A dry, single-seeded, non-endospermic fruit developing from an inferior bicarpellary ovary with basal placentation, typical of Asteraceae.

Caryopsis

A dry, single-seeded endospermic fruit (grain) where the pericarp is completely fused with the seed coat, characteristic of Poaceae.

Ray Florets

Peripheral, zygomorphic, ligulate florets of the Asteraceae capitulum that are typically female ($\text{♀}$) or neuter, with stamens absent ($\text{A0}$).

Disc Florets

Central, actinomorphic, tubular florets of the Asteraceae capitulum that are typically bisexual with syngenesious stamens.

Pyrethrum

A natural insecticide derived from Chrysanthemum cinerariifolium or Chrysanthemum marshallii, members of the Asteraceae family.