Pharmacognosy I Lecture 2 (Anatomy) - New Mansoura University PDF
Document Details
New Mansoura University
Ahmed Elbermawi, PhD
Tags
Summary
This document is a lecture on pharmacognosy, focusing on plant anatomy including substances, inclusions, and cell structure. It details cell walls, proteins, fats, and carbohydrates, with associated tests.
Full Transcript
NewMansoura University Faculty of Pharmacy PharmDProgram ___________________________________________________________________________ Pharmacognosy I Lecture 2 اﶈﺎﴐة اﻟﺜﺎﻧﯿﺔ Ahmed Elbermawi, PhD Lecturer of...
NewMansoura University Faculty of Pharmacy PharmDProgram ___________________________________________________________________________ Pharmacognosy I Lecture 2 اﶈﺎﴐة اﻟﺜﺎﻧﯿﺔ Ahmed Elbermawi, PhD Lecturer of Pharmacognosy 1- Middle Lamella / calcium and magnesium pectate 2- The primary cell wall/cellulose/capable of extension Cell wall 3- The secondary cell wall/When the cell ceases to enlarge/cellulose, lignin/incapable of increase in area pits regions in the cell wall in which no secondary wall is deposited plasmodesmata strands of cytoplasm connect the protoplasm of one cell with that of the adjacent cell plasma membrane phospholipid Bilayer/ selectively permeable/ Sensory transduction Nucleus controls all the activities/ transmission of hereditary characters Endoplasmic reticulum Smooth ER lacks ribosomes/ makes proteins USED in the Cell Rough ER has ribosomes/ proteins to EXPORT Ribosomes minute spherical bodies/ high protein synthesis Golgi apparatus cell wall formation/ receives proteins from ER transported to various destinations Mitochondria powerhouse of the cell/ produce necessary energy Plastids Leucoplasts/ colorless plastids Chromoplasts / carotenoid pigments Chloroplasts/ contain chlorophyll/ photosynthesis Lysosomes digestive enzymes/ Intracellular digestion Vacuoles filled with cell sap/ Tonoplast/ contain pigments as anthocyanin * Match the following statements (write only the numbers next to the matched sentence). Item Sentence 1 Rough Endoplasmic Outgrowth of the cell arises and becomes Reticulum impregnated with calcium carbonate 2 Plasmodesmata Powerhouse of cell 3 Cystolith Small strands of cytoplasm connecting to adjacent cells. 4 Mitochondria Attached by ribosomes Mark True (√) or false (X) 1- Primary cell wall are thicker and stronger, and they ( ) are deposited when most cell enlargement has ended. 2- Chromoplasts are non-pigmented plastids some of ( ) which synthesize starch 3- Nucleus is a Central leader of the cell. Surrounded by ( ) nuclear envelope. Contains directions to make proteins and genetic information, DNA or RNA. 4- Vacuoles are membrane bound organelles filled with ( ) cell sap Ergastic substances (Cell inclusions) The materials present in the vacuoles are known as ergastic. They are either reserve substances that may be utilized by the protoplast, for vital activities or they are by-products of metabolism. Ergastic substances occur in the vacuoles and in the cell wall, and may be associated with the protoplasmic components of the cell. They are of two types:- (1)Food-storage products (carbohydrates, proteins, fixed oils and fats). (2) Waste products (they are excretion of plant cells formed as a result of metabolic activities of protoplasm, i.e. by-products of metabolism). Food-storage products (A) Carbohydrates (cellulose and starch) Cellulose is the main constituent of the cell wall, where as starch occurs as reserved materials in the protoplast. Both are composed of long chain of glucose units. Starch is usually found in the form of granules of various shapes which may be for the plant type and used for its identification. Acid hydrolysis of starch gives glucose while hydrolysis with β- amylase enzyme yields maltose. Maize starch Characters: 1- Rectangular in shape with rounded angles. 2- Centric hilum. 3- Cleft or fissured hilum. 4- No striation. Potato starch Characters: 1- Oval or rounded in shape 2- Eccentric hilum. 3- Dot hilum. 4- Have striations. Tests for identity I. Microscopic examination: to detect the source of starch: maize, rice, potato and wheat starch. II. Iodine test: starch gives blue color with iodine solution. B- Protein Proteins are stored as aleurone grains. Proteins are polypeptide of amino acids linked together by peptide linkages. Aleurone grains are stained red with Millon reagent, yellowish brown with iodine solution and yellow with picric acid, leaving the globoids unstained. C- Fats They are mixtures of esters of fatty acids and glycerol, usually called glycerides, triglycerides or glyceryl esters. They are of two types: Solid: wax, suberin, fat and cutin. Liquid: fixed oils. ✓ Brown or black with a 1% solution of osmic acid. ✓ Red with Suddan III and dilute tincture of Alkana. Waste products Formed within an elongated epidermal cell a small outgrowth of the cell arises and becomes impregnated with calcium carbonate clusters known as (cystolith) اﻟﺒﻠﻮرات They are very common cell content in the plant kingdom and may function to deter herbivores from eating plant parts. They are nature's way of discouraging animals and other pests from eating these plants. Crystals calcium oxalate Calcium carbonate crystals dissolve with effervescence in dilute acetic, hydrochloric or sulphuric acid. Calcium oxalate crystals are insoluble in acetic acid but dissolve without effervescence in hydrochloric and sulphuric acid Discus the following figure and complete: The type of crystals is………………….. This starch has ………striations with …………..…hilum That is a crystals of …………….. The cell theory In plants with well defined tissues, the production of new cells is performed by certain growing regions called meristems. Tissues are generally divided into: Meristematic (have the ability to divide). ا ٔ ﺴ ﺔ ﺸﺎﺋﯿﺔ Permanent types. ا ٔ ﺴ ﺔ ا اﲚﺔ Classification of meristems They are classified, as regards their position in the plant body, into : Apical: located at the apices of main and lateral shoots and roots. Intercalary: lie at the internodes of monocot plants.. Lateral: arranged parallel with the sides of the organ such as the vascular cambium, cork cambium and interfascicular cambium. 3)lateral: arranged parallel with the sides of the organ such as: a- cork cambium (phellogen): It divides tangentially producing cork cells to the outside and phelloderm to the inside. b- vascular cambium: located between the xylem and phloem. c- interfascicular cambium: originates between vascular bundles of the stem. The primary permanent structure of the plant Those which lost their power of division. They may be classified according to their function, structure and position in the plant body. They may be pictured as composed of four systems of tissues: A- The dermal B- The ground C- The vascular D- The secretory tissues A) The dermal or protective tissue This is the system forming and the outer protective covering the plant (the epidermis). The epidermal cells are living. There are no intercellular spaces between the epidermal cells forming a continuous layer except in certain regions, especially on leaves and green stems, there stomal pores are found. Isodiametric cells in Elongated in dicot leaves monocot leaves The external epidermal wall may be differentiated into three layers: 1- The innermost made of pure cellulose. 2- A middle cutinised layer, made of a mixture of cellulose and cutin ( a fatty material). 3- An outermost layer having the highest percentage of cutin and known as cuticle. The cutin is impermeable to water and gases, and so the cuticle controls the water loss from the underlying cells. Stomata اﻟﺜﻐﻮر Openings in the epidermis mainly on the lower surface of the leaf that regulate gas exchange in the plants. Stomata consists of: 1- Guard cells Kidney-shaped in dicots Dumbbell-shaped in monocots 2- Subsidiary cells (2 or more cells) Dicot stomata Monocot stomata Epidermal modification and appendages The are commonly known as hairs or trichomes. According to their function, they may be classified into glandular and non-glandular epidermal appendages. What is the type of stomata ? A B C D * Mention the name, tissue and the function. A B