Choose true or false. Each right answer scores 1, and each wrong answer scores -1. Not answered questions score 0. True False 1) Because of the chemical composition, the cell walls of collenchyma cells are flexible, whereas the cell walls of sclerenchyma cells are stiff. 2) The primary cell wall of collenchyma cells is very thick and lignified. 3) Collenchyma cells work as support elements in those organs that are growing in length. 4) The large amount of cellulose in the cell walls of the collenchyma cells is responsible for the flexibility and resistance of this tissue. 5) Lacunar collenchyma lacks intercellular spaces. 6) Living cells are found in the mature collenchyma, while mature sclerenchyma cells die during differentiation. 7) Sclerenchyma cells may form large populations of cells, small groups, or scattered individual cells. They may appear in any body organ, showing either primary or secondary growth. 8) Sclerenchyma fibers may be used to form textile materials such as jute, hemp, or flax. 9) Extraxylary fibers are sclerenchyma fibers that are associated only with the phloem. 10) Sclereids are cells found as individual cells and show a diverse morphology. Click the images to enlarge F-1) Points encircle an angular colenchyma tissue. F-2) These cells are components of a lacunar collenchyma. F-3) Asterisks indicate the intercellular spaces of an annular collenchyma. F-4) Dots surround an annular collenchyma. F-5) Arrows point to perivascular sclerenchyma. F-6) Points enclose sclerenchyma fibers.
