Class 11th Biology  Hand written Notes 

🥀🌾Notes on Anatomy of Flowering Plants🥀🌾


Depending upon distribution of stomata, the leaves square measure :

(a) Apple-mulberry type: e.g. Oxalis, Mulberry, Apple.

(b) Potato type: e.g. biface (dorsiventral leaves of pea, bean, tomato).

(c) Oat type: e.g. Suberect (isobillateral) leaves of most grasses and cereals (monocotyledens).

(d) Nymphea type: e.g. Floating leaves of magnoliid dicot genus, Nymphia, water lily.

(e) Potamogeton|monocot genus|liliopsid genus} type: e.g. Submerged plants like hydrophytic plant, genus Vallisneria, Potamogeton.



(iv) Trichomes: These square measure epidermic outgrowths gift briefly or for good on most plant elements.


(v) Root hairs: they're enlargements of special epiblema cells known as trichoblasts and happens during a explicit zone of young root known as plant organ zone.


(2) Ground or elementary tissue system: Ground tissue system includes all the tissues of plant body except epidermic tissue system and tube tissues. It forms the majority of body. This tissue system primarily originates from ground plant tissue. the bottom tissues represent the subsequent elements :


(i) Cortex: It lies between stratum and also the pericycle. The cortex is distinct in dicotyledons however not in monocotyledons wherever there's no clear demarcation between cortex and pith. it's additional differentiated into :


(a) Hypodermis: it's collenchymatous in angiosperm stem and sclerenchymatous in monocotyledon stem. It provides strength.


(b) General cortex: It consists of parenchymatous cells. Its main operate is storage of food.


(c) Endodermis (Starch sheath): it's largely single superimposed and is formed of parenchymatous barrel formed succinctly organized cells.


(ii) Pericycle: it's one superimposed or multilayered cylinder of thin-walled or thick-walled cells gift between the endodermis and tube tissues. In some cases, the pericycle is formed of several layers of sclerenchymatous cells (Cucurbita stem) or within the type of alternating bands of thin-walled and thick-walled cells (Sunflower stem).


(iii) Pith or Medulla: It occupies the central half in angiosperm stem, and monocotyledon root. it's largely created of parenchymatous cells. in angiosperm root pith is totally obliterate by the metaxylem parts. In angiosperm stem the pith cells between the tube bundles become radially elongated and referred to as primary medullary rays or pith rays.


(3) plant tissue system: The central cylinder of the shoot or root enclosed by cortex is termed stele. The variable range of tube bundles fashioned within the stele represent plant tissue system. Xylem, vascular tissue and cambium square measure the main elements of the fibrovascular bundle. fibrovascular bundle could also be of following types:


(i) Radial: The vascular tissue and vascular tissue strands alternate with one another separated by parenchymatous cells. such forms of tube bundles square measure known as radial and located primarily in roots.


(ii) Conjoint: A fibrovascular bundle having each vascular tissue and vascular tissue along, is termed conjoined. commonly the vascular tissue and vascular tissue occur within the same radius. They occur in stems. Such tube bundles square measure of 2 types:


(a) Collateral: A fibrovascular bundle within which the vascular tissue lies towards outerside and vascular tissue towards inner aspect, is termed collateral, e.g., Sunflower.


(b) Bicollateral: A fibrovascular bundle having the vascular tissue strands on each outer and inner aspect of vascular tissue, is termed bicollateral. e.g., Cucurbita.