Plant Anatomy - 2013

Chapter 5. INDEPENDENT STUDENT RESEARCH WORK. ANATOMICAL STRUCTURE OF VEGETATIVE ORGANS

Objects of Study:

1) roots with Primary Structure in monocotyledonous plants — spider plant (Chlorophytum), iris, corn;

2) roots with primary structure in dicotyledonous plants — buttercup, valerian (Valeriana officinalis);

3) roots withfascicular structure in dicotyledonous plants — pumpkin (Cucurbita pepo), sorrel (Rumex acetosa);

4) roots with non-fascicular structure in dicotyledonous plants — elecampane (Inula helenium), marsh mallow (Althaea officinalis), carrot, parsley;

5) stems of monocotyledonous plants — corn, rye;

6) stems with fascicular structure in dicotyledonous plants — red clover, common sunflower, creeping buttercup, garden or horse sorrel, dill, pumpkin;

7) stems with non-fascicular structure in dicotyledonous plants — motherwort (Leonurus), cultivated flax, European elder, deadly nightshade (Atropa belladonna), guelder rose;

8) rhizomes of monocotyledonous plants — sweet flag (Acorus calamus), couch grass (Elytrigia repens), lily of the valley, iris;

9) rhizomes with fascicular structure in dicotyledonous plants — Bergenia crassifolia, bistort (Bistorta officinalis), tormentil (Potentilla erecta);

10) rhizomes with non-fascicular structure in dicotyledonous plants — peppermint (or other species), red raspberry;

11) rhizomes of pteridophytes — bracken fern, male fern (Dryopteris filix-mas);

12) leaves of monocotyledonous plants — spider plant, amaryllis, asparagus, wandering jew (Tradescantia);

13) leaves of dicotyledonous plants — geranium, sage, lemon, myrtle, oleander, lingonberry, violet, azalea;

14) leaves of gymnosperms — needles of: Scots pine, Norway spruce, Siberian pine, silver (or Siberian) fir.

Materials and equipment: microscopes, Glass slides and coverslips, razor blades, needles, tweezers, Petri dishes, dropper bottles, distilled Water, chloral hydrate solution, Sudan III solution, filter paper, charts: "ROOT of a monocotyledonous plant (iris)"; "Introduction/19.html">Primary structure of a dicotyledonous root"; "Fascicular structure of a dicotyledonous root (pumpkin)"; "Non-fascicular structure of a dicotyledonous root (fragment)"; "Tertiary root structure (beet root crop)"; "Stem structure of a monocotyledonous plant (corn)"; "Stem structure of a monocotyledonous plant (rye culm)"; "Fascicular structure of a dicotyledonous stem (fragment)"; "Non-fascicular structure of a woody plant stem (linden)"; "Non-fascicular structure of a woody plant stem (pine)"; "Structure of a monocotyledonous rhizome (lily of the valley)"; "Fern rhizome structure (diagram)"; "Leaf structure of a monocotyledonous plant (iris)"; "Isobilateral leaf structure

of a dicotyledonous plant (eucalyptus)"; "Bifacial leaf structure of a dicotyledonous plant (lingonberry)"; "Stomatal complexes of dicotyledonous leaves".

Tasks 1–10.

Prepare a microslide of a transverse section of an axial plant organ (root, stem, or rhizome), study its Anatomical Structure, draw a diagram and an anatomical fragment, and describe the research findings.

Prepare several thin transverse sections of the organ, striving to make them strictly transverse. Transfer the thinnest sections onto a glass slide and mount a temporary slide in a chloral hydrate solution. Clear the specimen and examine it first under low and then under high Microscope magnification.

Identify the anatomical Zones of the organ: protective tissue, cortex, and central vascular cylinder ( stele). Pay special attention to the tissue located in the exact center of the organ (xylem, pith, or hollow cavity) to determine the type of organ. Within each anatomical zone, identify all constituent Tissues. Pay special attention to the central cylinder and the arrangement of Vascular Tissues (phloem and xylem) — whether in separate bundles or continuous zones — and thereby determine whether the structure is fascicular or non-fascicular. Locate the mechanical Tissues of the central cylinder. Determine the presence or absence of cambium in the vascular bundles, the positioning of xylem and phloem, and name the type of vascular bundles. Pay attention to the arrangement pattern of the bundles (scattered, alternating, or circular) and classify the plant accordingly (monocot, dicot, or pteridophyte). Examine the cortical region of the organ. Identify the mechanical tissues and their types (collenchyma, sclerenchyma). Observe the thickenings of endodermal Cells: horseshoe-shaped or Casparian strips. Determine the type of fundamental parenchyma in the cortex (chlorenchyma, aerenchyma, storage parenchyma). Inspect the fundamental parenchyma for crystalline inclusions, secretory cells, or secretory cavities. Study and determine the type of protective tissue (epidermis, periderm, epiblem). Identify any trichomes present on the epidermis.

Under low magnification, draw a diagram of the Anatomical structure of the organ, and under high magnification, draw a fragment of the transverse section. Label the organ zones, their constituent tissues, and cellular inclusions on the drawings. Add appropriate captions to the drawings.

Describe the research results in the form of Conclusions. State the plant Class and the type of anatomical STRUCTURE OF THE organ.

Tasks 10 - 15.

Prepare a transverse section slide of the leaf, examine its anatomical structure, draw a diagram and a detailed fragment of the anatomical structure, and describe the research findings.

Using elderberry pith, make several strictly transverse sections of the leaf across the main vein. Separate the sections from the pith, transfer them onto a glass slide, and prepare a temporary mount in a solution of

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chloral hydrate. Clear the preparation and examine it under low and high microscope magnification. Identify the anatomical zones of the leaf: the dermal tissue, mesophyll, and vascular bundles. Analyze all tissues within these zones and locate any Cell inclusions, secretory cells, and secretory structures (if present). Determine the cuticle thickness on the upper and lower epidermis. Pay attention to the MICROSTRUCTURE OF THE upper and lower epidermis (determine which is upper and which is lower based on cell size). Carefully examine The structure of the mesophyll cells and determine whether the mesophyll is uniform or differentiated into palisade and spongy parenchyma. Examine the vascular bundle of the midrib, noting the arrangement of the phloem and xylem. Identify the types of mechanical tissues located directly beneath the epidermis and adjacent to the phloem and xylem. Investigate cell inclusions, internal and External secretory structures, and trichomes. Stain the preparation with Sudan III.

Under low magnification, draw a structural diagram, and under high magnification, draw a fragment of the leaf blade's anatomical structure from the cross-section. Label the anatomical zones of the leaf, the tissues of each zone, the vascular bundle with its constituent tissues, and cell inclusions on the drawings. Add captions to the drawings, specifying the name of the leaf's anatomical structure and the plant class. Describe the research results in the form of conclusions.

Tasks 10a - 15a.

Prepare surface view mounts of the upper and lower epidermis of the leaf.

This task should be performed after completing the previous assignment, namely, studying the Internal Structure of the leaf from a transverse section.

Peel off the upper and lower epidermis from the leaf previously studied in cross-section. Prepare mounts using a chloral hydrate solution, clear them, and examine them alternately under low and high microscope magnification. Pay attention to the distribution of Stomata and the shape of the epidermal cell walls. Identify the stomatal complex based on the shape and number of adjacent cells. Locate trichomes and determine their types. Note any cell inclusions. Based on the analysis, determine the class to which the studied plant belongs. Stain the preparation with Sudan III.

Under high magnification, draw fragments of the upper and lower epidermis showing three to four stomata, neighboring and epidermal cells, all types of trichomes, and cell inclusions (if present). Label all Structural components of the epidermis on the drawings. Add captions to the drawings. Summarize the research findings in your conclusions.