Morphology of Medicinal Plants PDF

MORPHOLOGY of PLANTS Prepared By J. Edmondson- Carter objectives At the end of this lesson students should be able to:  Explain the similarities and differences of Eukaryotic and Prokaryotic cells.  Differentiate between an animal and plant cell. Id...

MORPHOLOGY of PLANTS Prepared By J. Edmondson- Carter objectives At the end of this lesson students should be able to:  Explain the similarities and differences of Eukaryotic and Prokaryotic cells.  Differentiate between an animal and plant cell. Identify the organelles of the plant cell and their functions. 11/05/2024 2 Definition Morphology a: branch of biology that deals with the form and structure of animals and plants b: the form and structure of any organism or any of its parts https://www.merriam-webster.com/dictionary/morphology 11/05/2024 3 Overview 1838 – Schleiden and Schwaan Cell theory – Plant and animal body – minute cells Living organisms Unicellular multicellular 11/05/2024 4 Overview Multicellular organisms Life activities – performed by co-ordination of several organs organs > tissues > aggregates of similar cells Unicellular organisms All activities are performed by same cell 11/05/2024 5 Overview Plants ranges from Unicellular Plants – yeast , green algae Differentiated higher plants consists of the vegetative phase of Roots, stems, Leaves, flowers, seeds forming stages (reproductive cycle) 11/05/2024 6 Overview Characteristics of the cell Definite shape ……. (exception amoeba, leucocytes ….) Oval, spherical, polyhedral, columnar, cylindrical, stellate Size O.5 µm - 20 µm 200 – 300mm (exceptional ….. Plant fibers / latex cells ) There are two types of cells Prokaryotic and Eukaryotic 11/05/2024 7 Prokaryotic cell 11/05/2024 8  Eukaryotic Cell 11/05/2024 9 Similarities and differences of the cells Eukaryotic and Prokaryotic Eukaryotic Prokaryotic 1. Eukaryotes consists of nucleus bounded by nuclear membrane Prokaryotes do not have the nucleus in cell structure. 2. Eukaryotes consist of membrane- bound subcellular organelles such as Prokaryotes do not have organelles mitochondria, endoplasmic reticulum, nucleus and Golgi complex. 3. Eukaryotes consist of many large Prokaryotes consist of small ribosomes ribosomes 4. Eukaryotes consist of many chromosomes which undergo the Prokaryotes consists of the single process of meiosis & mitosis during chromosome cell division 5. Eukaryotic cells are reproducing only by sexual division Prokaryotes are on reproduced by 11/05/2024 asexual division 10 Similarities and differences of the cells Eukaryotic and Prokaryotic Eukaryotic Prokaryotic 7. Lysosomes and peroxisomes are Lysosomes and peroxisomes are present in Eukaryotic cells. absent in the prokaryotic cell. 8. Microtubules are present in Microtubules are absent in the Eukaryotic cells. prokaryotic cell. 9. The endoplasmic reticulum is The endoplasmic reticulum is absent present in Eukaryotic cells. in the prokaryotic cell. 10. Mitochondria are present in the Mitochondria are absent in the eukaryotic cell. prokaryotic cell. 11. The cytoskeleton is present in the The cytoskeleton is absent in the eukaryotic cell. prokaryotic cell. 12. True Membrane bound Nucleus True Membrane bound Nucleus are are present in eukaryotic cell. absent in prokaryotic cell. 11/05/2024 11 Differences between Animal and Plant cells Animal cell Plant cell 1. cell wall absent Cell wall present 2. Plasma membrane is the outermost Cell wall is the outermost boundary of boundary of the cell the cell 3. Plastids are absent Plastids are present 4. Lysosomes are present Lysosomes are absent 5. Pair centriole is present Pair centriole is absent 6. Vacuoles are absent if observed are Large central Vacuoles is present many and small 7. Phagocytosis or Pinocytosis is Phagocytosis or Pinocytosis is not observed observed 8. Golgi apparatus is present with Golgi apparatus is scattered in the specific polarity cytoplasm 11/05/2024 12  Organelles of the plant cell Organelles Functions 1. Cell wall I. Ridge frame-work and protection to protoplast II. Thick and lignified cells of the plant provide mechanical support III. Control the rate of transpiration due to cuticular sheath IV. The developing wall pressure prevents distention of 11/05/2024 protoplast. 13  Organelles of the Plant Cell Plasma Membrane Organelle Functions Plasma I. It is selectively permeable Membrane controls transport material across it. II. Permits diffusion of water and fat-soluble components. III. Fat insoluble components forms reversible compounds with membrane protein to pass 11/05/2024 through the membrane14  Organelles of Endoplasmic Reticulum the Plant Cell functions I. Due to ribosomes it involves protein synthesis also in fat metabolism II. Gives mechanical support to cytoplasm III. Participate in exchange of materials by active and passive transport 11/05/2024 15  Organelles of Ribosomes the Plant Cell Organel Function le Degradation and synthesis of protein 11/05/2024 16  Organelles of Golgi Complex the Plant Cell Organell functions e I. Condensation of lipids, carbohydrates hormones II. Participates in the formation 11/05/2024 Lysosomes 17  Organelles of Mitochondria the Plant Cell Organell Functions e Mitochondria I. Mainly transforms chemical energy into biological energy in form of ATP compounds II. All enzymes involved in the Krebs cycle are present in the mitochondria. 11/05/2024 18 III. Responsible for  Organelles of the Plant Cell Plastids Organel Functions le Plastids I. Vital role plant metabolism. Chloroplasts capture solar energy and converts it to chemical energy 11/05/2024 (photosynthesis) 19 Organelles of Nucleus the Plant Cell Organelle Functions Nucleus I. Controls all activities of the cell Biogenesis of ribosomal proteins only take part in the nucleolus Part of cell division 11/05/2024 20 Organelles of Nucleolus the Plant Cell Organelle Functions Nucleolus I. Responsible for secretion of the ribosomes, subunits II. Composes of two nucleic acids Deoxyribonucleic acid (DNA) (chromosome form) Ribonucleic acid (RNA) 11/05/2024 (Granular form 21 ) Organelles of Chromosomes the Plant Cell Organell Functions e Chromosomes I. Important role in heredity Mutation Variation II. Self-reproduce 11/05/2024 22 Cell Inclusions Cell Inclusions Aka ERGASTIC substances of Plants  Reserved foods – carbohydrates, protein, lipids  Excretory /End products of metabolism - tannins, resins, latex, volatile oils, chemical like alkaloids, glycosides and mineral crystals ( calcium oxalate, calcium carbonate, silica )  Secretory- various other products formed in the plant that serve other important functions but not covered in the above 11/05/2024 23 Ergastic Substances Reserve foods I. Carbohydrates a. Water soluble - Glucose, Fructose, Sucrose b. Water insoluble – Polysaccharides Inulin (Exception )  Inulin a. Only water-soluble polysaccharide b. Found in Dahlia and Dandelion c. Forms crystal spheres in alcohol  Starch a. Polysaccharide b. Found in tubers, food grains and Seeds c. Granules, concentric or eccentric d. Present as a blue colour in dilute iodine solution 11/05/2024 24 Ergastic Substances Reserve foods Carbohydrates (Cont’d) Cellulose a. Complex polysaccharide (cell walls, structural material of a plant) b. Mucilage (Forms gummy solution in epidermal cells) in Senna, Isapgol, linseed II. Proteins Nitrogenous compounds – soluble or insoluble in water vital to the structure and function of living cell Produced and associated with living matter Amorphous – (maize – aleuronic layer) or Crystalline – (castor seeds- aleuronic grain) Converted by proteolytic enzymes to amino acids 11/05/2024 25 Ergastic Substances Reserve foods iii. Lipids Oils – liquid at room temperature Fats – Solids at room temperature Made up of fatty acids and glycerin oils Oils are found in the endosperm – seeds of castor, peanut, sesame 11/05/2024 26 Ergastic Substances EXCERTORY PRODUCTS 1. Alkaloids Basic secondary metabolites ( nitrogenous) marked physiology action Occurs as salts – nicotinic, quinic, citric /oxalic acids Found – seeds, barks, leaves, roots Highly potent medicaments and possess curative properties Protective materials of the plant (animal or insect attack) Detoxifying agents of plants Reservoirs for Protein synthesis E.g. ergot, Vinca, Datura ii. Glycosides Condensation products of sugar and glycol Secondary Metabolites – (pharmaceutical significance) Dissolves in water and alcohol 11/05/2024 Examples – Digitalis, Senna, Rhubarb 27 Ergastic Substances EXCERTORY PRODUCTS iii. Tannins Present Cell sap Soluble in water and alcohol Give blue black or green colour in the present of iron Several medicinal properties ( drugs) e.g. Nutgalls, Myrobalan, IV. Resins Resins Ducts Insoluble in water Semisolid or solid Associated with gums / volatile oils 11/05/2024 28 Ergastic Substances Excretory Products Latex A white suspension, with microscopic particles or oil globules suspended Contains protein, sugars, minerals, and alkaloid salts in true solution Gums, starch, resins are is suspended form It is present in lactiferous tissue- Euphorbiaceae, Caricaceae, Papaveraceae, Examples – Banyan, madar, Papaya, Poppy, Ficus. Volatile Oils: Fragrant liquids in plants Volatile , liquid, and aromatic Present in leaves, stems, bark, and fruit Insoluble in water and soluble alcohol Carminative stimulants and antiseptic (Used as drugs) 11/05/2024 Examples- orange, lemon, coriander, cinnamon, ginger, 29 Ergastic Substances Excretory Products Minerals Crystals Occurs in cell wall or cell cavity Insoluble in water Found – roots, stem, leaves, fruits Common crystals – calcium carbonate - calcium oxalate (various types (prism like) Example – acicular, Raphides, Cluster of rosettes 11/05/2024 30 Ergastic Substances Prismatic crystals 11/05/2024 31 Ergastic Substances Acicular crystal 11/05/2024 32 Ergastic Substances Secretory Products Secretory Formed in plants and serve important functions products 1. enzymes  colouring substances /Pigments Chlorophyll-Essential for photosynthesis, anthocyanin(others)  Flavonoid glycosides- gives attractive colours to flowers  nitrogenous water-soluble compounds Hydrolysis of carbohydrates and protein 2. Nectar  Sugary solution Secreted by many flowers in special cells and glands 11/05/2024 33 Plant Tissues Plant or Animal Organ are composed of various tissues In a specific organ, Various tissues perform interrelated functions Tissues an aggregation of cells /elements having the same function 11/05/2024 34 Plant Tissues Classification Origin structure Physiology TISSUES classification Meristematic or Embryonic Permanent tissue 11/05/2024 35 11/05/2024 36 Plant Tissues - Meristematic Meristematic or embryonic characteristics 1. Small cells and isodiametric in nature 2. Cells are compact with no intercellular spaces 3. Cells are thin walled , cubical and prominent nucleus 4. Vacuoles are very small or absent 5. Cells have the capacity to multiply 6. Newly formed cells 11/05/2024 Due to enlargement or morphological differentiation 37 Plant Tissues- Meristematic or Embryonic 11/05/2024 38 Plant Tissue 11/05/2024 39 Plant Tissues –Permanent Permanent Tissues characteristics 1. Cells vary in size, shape, nature of protoplast 2. Cells may be living or dead 3. Produced by meristematic cells 4. Do not have the capacity to multiply 5. Normally retain their structural physiological characters Not usually changed into other kind of tissues 6. They are composed of one or more type of cells 11/05/2024 40  Plant Tissues- Permanent Tissue 11/05/2024 41 Plant Tissues Permanent Tissues Simple Tissue Complex Tissue 11/05/2024 42 Permanent Tissues - Simple 11/05/2024 43 Permanent tissues - Complex 11/05/2024 44 11/05/2024 45 Plant Tissues- Simple Permanent Tissue 1. Outermost layer plant structure Normally one cell thick- Epidermis Conserve moisture supply and protect against mechanical infection Cover with fatty substance (cutin) Made up of Parenchyma Occurs of the surface layers of leaves, stems flower, fruits and seeds Cells are colourless unless pigment is present Minute openings ( stomata ) 11/05/2024 epidermal hairs (trichomes 46 Plant Tissues- Simple Permanent Tissue Epidermis 1. - May vary cells cont’d - Straight walled polygonal (Senna leaf) - Thick walled beaded (Digitalis) - Wavy (Hyoscyamas) - Wavy and with striated cuticle (Belladonna) - Papillose ( stigma of pyrethrum flowers) 11/05/2024 47 Permanent Tissue - Simple 2. Parenchyma a) Found in all organs of higher plants b) Cells thin-walled polyhedral in shape Large vacuole (most cases) c) Aging Change in shape Wall thickening Appearance of intercellular space FUNCTION: 1. Stores food and water 2. Manufacture food 3. Excretion and secretion 4. assimilation 11/05/2024 48 Permanent Tissue - Simple Parenchyma. Secondary thickening – Cont’d a) Simple Parenchyma b) Parenchyma with intracellular spaces c) Lignified parenchyma d) Reticulate Parenchyma 11/05/2024 49 Permanent Tissue - Simple 3. supporting tissue , Sclerenchyma mechanical function roots, leaves , stems, xylem, other parts very hard , strengthening organs two elements a) Stone cells - Isodiametric - - Elongated / branched - - Pitted / stratification (observed) - - Groups, single, / complete layers - - Abundant - cortex , Phloem ( stems, leaves, roots) seeds/ flesh of fruits 11/05/2024 50 Permanent Tissue - Simple Sclerenchyma b) Fibers Cont’d - develop in bundles or layers - thick-walled, narrow lumen pointed end - lumen walls lignified - Contain cellulose - Pericyclic, xylem or phloem (fibers) - Sheath of crystals is formed around sclerenchyma (eg. Senna 11/05/2024 leaf) 51 Permanent Tissue - Simple 4. Collenchyma - Supporting tissue - Similar to parenchyma ( except primary cell wall is thicken to give mechanical strength - May /may not - Intercellular space - Contain chloroplasts - Thickening maybe - Stratified or evenly distributed around the lumen 11/05/2024 52 Permanent Tissue - Simple Cork Simple permanent tissue Made of compactly arranged prismatic cells - radial rows No intercellular spaces ) Forms bark of stems and roots Function o Protective o Prevents loss of water Dead cells Protoplasm dies > matured cells are dead 11/05/2024 53 Permanent Tissue - Complex Complex tissue - Several types of cells are present - Engage in a closely related actives a) Xylem :  Main water conducting tissue  Associated with the Phloem in the vascular tissues  Components  Parenchyma  Fibers  Tracheary elements o Tracheid o Vessel members o Elongated in structure o Non-living in nature 11/05/2024 54 Permanent Tissue - Complex Complex A) Xylem- - Thickened xylem vessels ( lignified) tissues Cont’d - Thickening of Xylem elements o Annular o Spiral o Reticulate o Pitted o Border pitted o Scalariform - Tracheid's are closed ( imperforated) - Vessels are opened at both end of tubes from the 11/05/2024 tube. 55 Permanent Tissue - Complex Complex B) Phloem Transport food tissues in leaves downward to stem and roots Cont’d Cells constituting Phloem Phloem Parenchyma ( ray cells) - store food Sieve tubes – contain living protoplasm End walls contain circular perforations (CP) CP- between the sieve tubes and companion cells Companion cells Phloem fibers – strength and support 11/05/2024 56 Permanent Tissue - Complex Complex C) Secretory Structure Important to secretory plants tissues Internal /external Cont’d Unicellular – oil glands and resins Multicellular – ducts / glands Formation of secretory structure: Schizogenous ( By splitting of cells ) Lysigenous (Breaking down of groups of cells) Schizolysigenous ( combination of the above two) Secretions: 1. Tannins 3. Mucilage 2. Oils (volatile /fixed) 4. Crystals 11/05/2024 57 Permanent Tissue - Complex Complex D) Lateciferous tissues tissues Aka milk tubes Cont’d Vessels or cells RUBBER Plant MADAR Plant White juice Thick or watery or white ( papaya, euphorbia) Coloured (orange in chinopodium & poppy) Vessels Branched Reunite forming a network Latex – chemicals Alkaloids Enzymes Protein Function – unknown 11/05/2024 58 Lateciferous tissues 11/05/2024 59 Conducting Tissues Conducting Vascular elements Transport of food material tissue system: Vertically placed Continuous from root to leaf Grouped in bundles ( vascular bundles) Consists of Xylem and Phloem Types of vascular bundles a) Radial - Arrange on alternate radii - Xylem an Phloem only - In the roots Xylem is exarch with proto- xylem - Proto-xylem points towards the periphery 11/05/2024 - Meta-xylem towards the Centre 60 Conducting Tissues- Vascular Bundles Complex tissues Types of radial bundles Cont’d Cont’d B) Collateral Xylem and Phloem are in the same radius Xylem – center Phloem – towards the periphery Types of collateral vascular bundles Open collateral Cambium placed between Xylem and Phloem ( dicotyledonous plants) Closed collateral No cambium present between Xylem and Phloem (monocotyledonous) 11/05/2024 61 11/05/2024 62 Vascular bundles- Conducting tissues 11/05/2024 63 Conducting Tissues – vascular bundles 3) Bi-collateral Complex tissues Xylem lies in the center Cont’d Cambium and Phloem on either side Vascular Bundles ( cucurbitaceous family) 4) Concentric No cambium a) Xylem lies in center surrounded by Phloem (Centroxylic) Or b) The phloem in the center surrounded by the xylem (centrophilic) Eg. Ferns 11/05/2024 64 Microscopy of Plants Various tissues Types were grouped in units known -Tissues Systems of plants These consists of: (a) Epidermal tissue system - outermost layer of all plant parts and its covering cuticle Consists Epidermis, Outgrowth (trichomes) openings (stomata, water pores) Function protection, aeration, control loss of water Enable absorption of water and minerals from the soil (via roots, root hairs) 11/05/2024 65 Epidermal Tissue System 11/05/2024 66 Microscopy of Plants Various tissues Ground tissue system Cont’d - includes epidermal and vascular bundles tissues - forms the bulk of the plant parts Consists – cortex - pericyclic medullary rays - pith in roots and stems - covers mesophyll of leaves Function Food formation Food storage Aeration Mechanical strength 11/05/2024 67 Ground Tissue System 11/05/2024 68 Microscopy of Plants Various Vascular tissue system tissues Consists – Xylem Phloem (with/without cambium) Cont’d Transport raw /ready food material Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem. 11/05/2024 69 Microscopy of Plants Vascular tissue system 11/05/2024 70 Study Assignments Structure of a) Types of epidermis cells b) Types of sclerenchyma, parenchyma, and collenchyma c) Types of cork cells d) Xylem and phloem elements e) Secretory structure f) Lateciferous tissue g) Conducting systems. h) Microscopy of plants. 11/05/2024 71  https://www.diffen.com/difference/Image:Plant -Cell.jpg Trease and Evans’ Pharmacognosy 13th edition. C.K. Kokate, A.P. Purohit, S.B.Gokhale Reference Pharmacognosy https://www.bing.com/images/search?q=lactif s: erous+plant+tissue https://cdn.biologydiscussion.com/wpcontent/ uploads/2016/12/clip_image004- https://www.bing.com/images/search?view=d etailV2&ccid=xdu82%2fW2&id=96858FAA6AF 4680A57C0FDB614641A591D400D3C&thid= OIP.xdu82_W2cJAKGBPccsTwmwHaEK&mediau rl=http%3a%2f%2fwww.brainkart.com%2fme 11/05/2024 dia%2farticle%2farticleGuc71aajradorrefer11.72 11/05/2024 73