PHA611 Plant Tissues and Classifications PDF

PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) [TRANS] I. II. III. IV. V. VI. VII. VIII. OUTLINE Importance of Histology Concepts: Plant Body Tissues a. Classification of Meristematic Tissues Basic Types of Simple Tissues a. Epidermis...

PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) [TRANS] I. II. III. IV. V. VI. VII. VIII. OUTLINE Importance of Histology Concepts: Plant Body Tissues a. Classification of Meristematic Tissues Basic Types of Simple Tissues a. Epidermis i. Specialized Epidermal Cell b. Trichomes i. Types of Trichomes c. Cork or Phellem d. Parenchyma e. Collenchyma f. Sclerenchyma g. Sclereids and Fibers Complex Permanent Tissues a. Xylem Tissues b. Phloem Secretory Cells External Glands Secretory Cells (internal) IMPORTANCE OF HISTOLOGY ● ● ● ● ● Evaluation of the therapeutic efficacy of herbal drugs o Ex. Preparing herbal drugs from certain plants. If collected the wrong specimen or part of a plant, it may be ineffective or lose its therapeutic value. It may lead to harmful adverse reactions and may lead to death. Evaluation of crude drug is an essential part of Pharmacognosy Microscopic assessment of powdered drugs Percent adulteration with foreign substance must be noted o Adulteration is the addition of unwanted materials o It may be accidental, intentional, or unintentional, however it is still bad since it can harm, poison, or even cause the death of a person Characterization and identification of plant source species CONCEPTS: PLANT BODY ● Plant body is divided into two o Primary plant body or herbaceous soft and succulent, no woody tissues present (e.g. leaves, flowers, fruits, some stems) o Secondary plant body or woody Primary Plant Body ● ● ● ● Derived from the apical meristems, either the root or shoot tips o Meristems are responsible for the production of new cells Composed of primary tissues Constitutes the herbaceous part of plant Present in herbs o Herbs that are 100% plant - onion, tomato, ginger, carrot, cabbage, wheat Secondary Plant Body ● ● ● ● Derived from the vascular cambium and cork cambium o Vascular cambium is composed of the secondary xylem (wood) and the secondary phloem (inner bark) o Cork cambium consists of the outer bark Composed of secondary tissues: wood and bark Constitutes the wood and the bark of old woody dicot Present in stem and gymnosperms (conifers) o Herbs that are 100% plant - onion, tomato, ginger, carrot, cabbage, wheat BORILLO, CABARDO, CRUZ K, PEÑAS 1 PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) TISSUES ● ● ● Group of cells that perform specific function or functions o Whether it is a primary or secondary plant body, they still contain tissues Classification: o Based on stage of development ▪ Embryonic or meristematic ▪ Permanent or mature o Based on composition ▪ Simple - composed of one type of cell/tissue ▪ Complex - made up of two or many types of cells performing specific types of functions Example o What kind of tissues make up the leaf? - All tissues in the lead are said to be permanent o Leaf bud - meristematic/embryonic since it is still producing new cells o Germinating seeds - meristematic o Root tip - meristematic, in onion root tip, the cells are actively dividing due to the meristems Simple Permanent Tissue Classification of Meristematic Tissues ● Based on initiating (originating) cells o Primary meristem (apical) - for elongation of root and stem ▪ Shoot apical meristem ▪ Root apical meristem o Secondary meristem (lateral) production of wood and bark ▪ Vascular cambium - separates wood from bark ▪ Cork cambium - phellem cells which are dead cells ● Based on position in the plant body ○ Apical o Intercalary ▪ Can be seen in the internodes ▪ For monocot plants, there is a dominant effect ▪ Elongates/lengthens due to intercalary Complex Permanent Tissue o BORILLO, CABARDO, CRUZ K, PEÑAS Lateral 2 PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) BASIC TYPES OF SIMPLE TISSUE (based on cell wall) ● ● Based on function o Protoderm o Procambium o Ground tissues Structure of an Apical Meristem ● Ground tissues are also known as the cortex tissues ● ● Parts of the apical meristem (tip) Longitudinal section of apical meristem Can be classified according to: o Type of cell wall o Type of protoplasm o Component (chemical) or deposition o Function Epidermal cells Cell Wall: Thin primary walls Protoplasm: Alive at maturity Component: Cutin Function: Protection and secretion Parenchyma Cell Wall: Uniformly thin primary walls Protoplasm: alive at maturity Component: Function: many functions ● Storage of starch (potato, radish, sweet potato) ● Pulpy fruits (apple, banana) ● Aeration or sometimes photosynthesis Collenchyma Cell Wall: Non lignified cell wall, unevenly thickened primary walls Component: Protoplasm: Alive at maturity Function: Plastic support Sclerenchyma Cell Wall: Primary and secondary walls Protoplasm: Many are dead at maturity but not all ● Some need to die to serve their purpose Component: Lignin Function: Provide elastic support and some are involved in water transport Ex. Fibers (abaca, coconut fibers) Phellem or cork Cell Wall: Impregnated with suberin Protoplasm: Dead at maturity Component: Suberin and lignin Function: Protection BORILLO, CABARDO, CRUZ K, PEÑAS 3 PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) Ex. Cork -waterproof and gas proof, Birkenstock slipper ● o Regulate exchange of materials Encrusted with cutin (cuticle) Specialized Epidermis Cell ● ● ● ● C - Collenchyma ● Deposition along corners where cells meet ● Thickening is due to presence of pectin (flexible molecule) which provides plasticity Differ in sizes and shapes Guard Cells - gaseous exchange and photosynthesis Accessory cells - serves as reservoir of water and ions Bulliform cells - longitudinal rows of vacuolated cells o Big vacuole - large capacity for storage and is turgid o Reservoir of fluids to prevent excessive water loss in monocot plant o Prevent desiccation of plant Epidermis (simple dermal) ● ● ● Simple (according to function) dermal (according to location) Outermost surface of a herbaceous stem, leaf, root Uses o Protection ● Epidermal hair - elongation of epidermal cell outward (trichome and root hairs) o Epidermal stem of leaf - trichome BORILLO, CABARDO, CRUZ K, PEÑAS 4 PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) o Epidermal stem of root - root hairs ● Trichomes - hairs of leaves, stems, and fruits ● ● Shape- kidney/ bean Boatlily - epidermal color violet Uses of Trichomes: ● Cotton trichomes can be made into threads, which are then woven into cloth ● Volatile or essential oil ● Resin glands in marijuana for THC and CBD ● Lipids in basil plants Trichomes (Epidermal Outgrowths/Hair) Functions of Trichomes: ● It shades leaves from excessive sunlight. ● It provides protection from insects. ● It aids in nutrient uptake. ● They aid in the spread of seeds. Types of Trichomes 1.) Glandular or Secretory a.) Glandular b.) Stinging BORILLO, CABARDO, CRUZ K, PEÑAS 5 PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) 2.) Non-glandular or Non-secretory a.) Bristle b.) Branching Cork or Phellem (Simple Dermal) Features: ● It has an outer covering of woody stems and roots. ● The cell wall is impregnated with suberin. ● This is produced by the cork cambium (secondary meristem). c.) Stellate d.) Scale ● Economic Importance of Cork Epidermal Hairs on Roots Features: ● It is a one-celled epidermal outgrowth. ● It is short-lived. ● This is found in the zone of maturation only. ● This is delicate. Function: ● This increases water and mineral absorption. This has no intercellular spaces. ● Cork is an impermeable, buoyant material, a prime subset of bark tissue that is harvested for commercial use primarily from Quercus suber (the Cork Oak). BORILLO, CABARDO, CRUZ K, PEÑAS 6 PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) Parenchyma (Simple Ground) ● ● ● ● ● This has a thin – walled primary wall. This is only alive at maturity. It has an isodiametric shape. A large vacuole. This has 4 types o Chlorenchyma – allow entry and exit of carbon dioxide o Aerenchyma – gas exchange o Transfer cells o Storage parenchyma ● ● ● Location of Parenchyma Sclerenchyma (simple ground) ● ● ● ● Storage parenchyma in tomato Storage parenchyma in potato Chlorenchyma in leaf tissues Aerenchyma in water hyacinth Adapted for support With pectin on cell’s corner Tendrils and bamboo plant Rigid, thick lignified secondary wall Dead at maturity (in some) Support and strengthen in non-extending parts of the plant Types of sclerenchyma 1. Mechanical or non-conducting ● Sclereids (stone cells) ● Fibers 2. Conducting (Tracheary elements) ● Tracheids ● Vessel elements Collenchyma (simple ground) ● Elongated cells with unevenly thickened non– lignified primary wall BORILLO, CABARDO, CRUZ K, PEÑAS 7 PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) Sclereids and Fibers Sclereids ● short with variable shapes ● singly or in small groups ● forms hard layer ● retains a living protoplasm Xylem Tissues ● Fibers ● long thick lignified slender cells ● single strands or bundles ● associated with vascular tissues ● elongates as the internode increases in length Economic Importance of Fiber Importance of fibers: ● Philippines fibers like abaca leaves, hemp and pineapple leaves are hard fibers ● Flax fibers – common source for paper and linen cloth ● Bamboo fiber ● Cotton fibers ● Rayon fibers ● ● ● transport water and minerals from the roots to stem - leaves thick lignified wall, dead at maturity 2 types: 1. Primary xylem is derived from procambium protoxylem and metaxylem 2. Secondary xylem (wood) is derived from vascular cambium 2 conducting cells (xylary elements): 1. Tracheids 2. Vessel elements COMPLEX PERMANENT TISSUES ● Xylem – brings water and mineral salts from the roots to the rest of the plants o Xylem fibers, xylem parenchyma, tracheids and vessel elements Tracheary Elements of Xylem ● Phloem – moves sugar and other organic nutrients ○ Phloem fibers, phloem parenchyma, sieve tube, companion cells Tracheids Vessel elements long cells with tapered ends wider, shorter, and less tapered only type of water conducting cells in ferns, conifers and most other non-flowering flowering plants BORILLO, CABARDO, CRUZ K, PEÑAS 8 PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) Phloem plants dead at maturity dead at maturity secondary wall has pits cell walls form hollow tubes, with perforation plate joined together to form long pipe ● ● ● ● transport dissolved organic compounds (sucrose) thin walled primary wall 2 types 1. Primary phloem – derived from procambium 2. Protophloem and metaphloem secondary phloem – vascular cambium 2 conducting elements o Sieve elements: ▪ Sieve cells ▪ Sieve tube members (companion cell) Tracheary elements of Xylem in microscope image (Stem) Two conducting elements of Phloem 1. Sieve Tube Members/ Cells ● Alive and active ● Presence of sieve plates ● No nucleus ● Forms continuous connection of ● Cytoplasm from the top to bottom 2. Companion ● Nucleated parenchyma ● Supply proteins to sieve tubes Secondary Wall thickenings in Tracheids and vessel elements BORILLO, CABARDO, CRUZ K, PEÑAS 9 PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) Herbaceous vs Woody Dicot EXTERNAL GLANDS 1. Nectary - secrete nectar or sugary exudates ● For attraction - Floral ● Protection - Extrafloral 1. 2. 3. 4. Scanner Helianthus stem HPO Helianthus stem Primary phloem (one year old) Secondary phloem - Ranunculus stem SECRETORY CELLS Not classified but incorporated with other tissues ● Two Types 1. External ● Nectary ● Hydathodes ● Digestive glands ● Salt glands 2. Internal ● Oil cells ● Oil ducts ● Resin ducts ● Laticifers 2. Hydathodes (water glands) - secrete water via guttation, relieve pressure build-up BORILLO, CABARDO, CRUZ K, PEÑAS 10 PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) 3. Digestive glands of Pitcher Plant 2. Resin ducts of pine trees - Resin contains mixture of volatile oil, terpenes, minerals 4. Salt glands in mangrove leaf ● Dump sites for excess salt absorbed from a salty (saline) environment 3. Laticifers - secretes latex ● Opium alkaloids 1. Morphine 2. Codeine 3. Heroin 4. Noscapine SECRETORY CELLS (INTERNAL) ● Internally located cells that exude protoplasmic products influenced by pressure or lysis of cell wall 1. Oil cells/ glands - secretes oil and mucilage PRACTICE QUESTIONS 1. Which of the following parts of plants is composed of purely mitotic tissues? a. Leaf b. Root tip c. Bark d. Wood 2. Which of the following choices is true? a. Phellem is found in inner bark. It is composed of dead protective cells. i. Inner bark- outer bark b. Root hairs are outgrowths of epidermal cell in any parts of the plant. They are usually short-lived. i. Any parts of the plantepidermis BORILLO, CABARDO, CRUZ K, PEÑAS 11 PHA611: PHARMACEUTICAL BOTANY WITH TAXONOMY LECTURE: UNIVERSITY OF SANTO TOMAS - FACULTY OF PHARMACY (1A-PH) c. There is no trichome in the bark of a plant. Trichomes are either secretory or non secretory. i. Trichomes are found in the epidermis and there is no epidermis in the bark. d. Epidermal cells are living cells. They have chlorophyll if found in the leaf. 3. Label the parts a. Monocot stem 1. Epidermis 2. Vascular bundles 3. Phloem 4. Xylem 5. Ground tissue b. Dicot stem BORILLO, CABARDO, CRUZ K, PEÑAS 12