TNPSC Free Notes Biology -Angiosperms

இந்தக் கட்டுரையில், TNPSC குரூப் 1, குரூப் 2, குரூப் 2A, குரூப் 4 மாநிலப் போட்டித் தேர்வுகளான TNUSRB, TRB, TET, TNEB போன்றவற்றுக்கான  முறைகள் இலவசக் குறிப்புகளைப் பெறுவீர்கள்.தேர்வுக்கு தயாராவோர் இங்குள்ள பாடக்குறிப்புகளை படித்து பயன்பெற வாழ்த்துகிறோம்.

Angiosperms

General Characters of Angiosperms:
 The term ‘Angiosperm ’is derived from two Greek words, i.e. ‘Angio’ which
means box or closed and ‘ sperma’ which means
seed.
 They occupy every habitat on earth except extreme environment (extreme
hot and cold conditions).
 Habit of the plants may be
1. herb (Solanaum melongena)
2. shrub, (Hibiscus rosasinensis) and
3. tree – (Mangifera indica Mango)
 They have well developed conducting tissues. (Vascular bundles)
 Xylem contains vessel, tracheid, xylem parenchyma and xylem fibre.
 Phloem contains sieve tubes, phloem parenchyma, companion cells and
phloem fibres.

Classification of Angiosperms:
Angiosperms are divided into two classes, They are:
1. Monocotyledons
2. Dicotyledons

Characteristic features of monocotyledons:
 Seed has only one cotyledon.
 Plants have fibrous root system, leaves with parallel venation.
 Pollination occurs mostly by wind. E.g. Grass, Paddy, Banana.

Characteristic features of Dicotyledons:
 Seed has two cotyledons.
 Plants have tap root system, leaves with reticulate venation.
 Pollination occurs mostly by insects. E.g. Bean, Mango, Neem

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