Biology · Anatomy of Flowering Plants · NEET
It depends on the type. Parenchyma and collenchyma are LIVING because their cells keep their cytoplasm and nucleus. Sclerenchyma is DEAD at maturity — the cells lose their cytoplasm and are left as empty, thick-walled boxes. So you cannot say all simple tissue is dead; only sclerenchyma is. NEET loves to trap you here, so remember: two living, one dead.
A SIMPLE tissue is made of ONLY ONE type of cell, so all its cells look and work the same way (parenchyma, collenchyma, sclerenchyma). A COMPLEX tissue is made of MORE THAN ONE type of cell working together (xylem, phloem). This is the exact line NEET 2021 tested: 'tissue having all cells similar' = simple tissue; 'tissue having different cells' = complex/vascular tissue.
There are THREE: parenchyma, collenchyma, sclerenchyma. Order them by how thick their walls get. Parenchyma = thin walls (soft, living). Collenchyma = thick only at the corners (flexible support, living). Sclerenchyma = thick all over with lignin (hard support, dead). As you go down the list, walls get thicker and support gets stronger.
Parenchyma cells are thin-walled, living, and loosely packed with air spaces between them. They fill up space in the plant body (cortex, pith, mesophyll) — that is why it is called packing or ground tissue. It is also the LEAST specialised, so all other tissues are thought to have evolved from parenchyma. For NEET, remember parenchyma also stores food and can do photosynthesis when it has chloroplasts (then called chlorenchyma).
No. 'Permanent' means the cells have lost the power to divide — they came from meristematic tissue, matured, and settled into a fixed job. This is the opposite of meristematic tissue, whose whole job is to keep dividing. So growth in length or thickness comes from meristems, not from parenchyma, collenchyma, or sclerenchyma.
Match List-I with List-II. List-I: (a) Cells with active cell division capacity; (b) Tissue having all cells similar in structure and function; (c) Tissue having different type of cells; (d) Dead cells with highly thickened walls and narrow lumen. List-II: (i) Vascular Tissues; (ii) Meristematic tissues; (iii) Sclereids; (iv) Simple Tissue. Choose the correct answer:
Statement I: Parenchyma is living but collenchyma is dead tissue. Statement II: Gymnosperms lack xylem vessels but presence of xylem vessels is the characteristic of angiosperms. In the light of the above statements, choose the correct answer:
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Parenchyma, collenchyma, and sclerenchyma. Parenchyma has thin living walls, collenchyma has walls thickened at the corners and is living, and sclerenchyma has thick lignified walls and is dead.
Only sclerenchyma is dead at maturity. Its cells lose their protoplasm and are left as hard, thick-walled empty cells (fibres and sclereids). Parenchyma and collenchyma stay living.
Simple permanent tissue is made of ONE cell type (parenchyma, collenchyma, sclerenchyma). Complex permanent tissue is made of MORE than one cell type working together (xylem, phloem).
Collenchyma is found below the epidermis, usually in the hypodermis of dicot stems and in leaf stalks (petioles). It gives flexible mechanical support to young growing parts and is living.
Parenchyma is living. Its cells have thin cellulose walls, a nucleus, and cytoplasm. It stores food, fills space, and can photosynthesise as chlorenchyma when it contains chloroplasts.
