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BOTANY Higher Secondary Second Year - Textbooks Online

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Permanent tissue<br />

The cells, which are formed by apical meristem, are differentiated<br />

into different types of permanent tissues. These tissues have lost the<br />

power of dividing either permanently or temporarily.<br />

Classification of permanent tissue<br />

Based on the constituent cells, the permanent tissue is classified into<br />

two types – simple tissue and complex tissue.<br />

Simple tissue<br />

A tissue with the cells of similar structure and function is called<br />

simple tissue. It is of three types - parenchyma, collenchyma and<br />

sclerenchyma.<br />

Parenchyma<br />

It is generally present in all organs of the plant. It constitutes the<br />

ground tissue in a plant. Parenchyma is the precursor of all the<br />

other tissues. Parenchyma is a living tissue and made up of thin walled<br />

cells. The cell wall is made up of cellulose. Parenchyma cells may be<br />

Nucleus<br />

Cytoplasm<br />

Vacuole<br />

Intercellular<br />

space<br />

Parenchyma tissue Storage parenchyma<br />

Inter cellular<br />

space<br />

Aerenchyma Palisade parenchyma<br />

Fig. 2.2 Types of parenchyma tissues<br />

70<br />

Starch grains<br />

Chloroplast

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