Anatomy of Flowering Plants
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Medullary rays: These are few layers of radially placed parenchymatous
cells in between vascular bundles.
Vascular bundles: Large in number. They are arranged in a ring. Ring
arrangement is a characteristic of dicot stem. Each vascular bundle is
conjoint, open, and with endarch protoxylem.
Pith: Central portion of the stem. It has many rounded, parenchymatous
cells with large intercellular spaces.
MØÑØÇØTÝLËDØÑØÜS (MØÑØÇØT) STËM
Epidermis
Hypodermis
Vascular
bundles
Ground
tissue
Epidermis
Hypodermis
Vascular bundles
Phloem
Xylem
Ground tissue
It has a sclerenchymatous hypodermis, many scattered
vascular bundles, each surrounded by a sclerenchymatous
bundle sheath, and a large, conspicuous parenchymatous
ground tissue. (NEET 2020)
The phloem parenchyma is absent, and water-containing
cavities are present within the vascular bundles.
(AIPMT 2012)
Vascular bundles are conjoint & closed. Peripheral
vascular bundles are smaller than centrally located ones.
DÏÇØTÝLËDØÑØÜS (DØRSÏVËÑTRÅL) LËÅF
The vertical section of a dicot leaf through lamina shows 3 main parts:
Epidermis, mesophyll & vascular system.