Botany for Pre-Medicine Students - PDF

Botany for Pre- Medicine students. Dr: M. A. Al-Ryani. Introduction In General Botany Botany is the scientific study of plants and plant-like organisms. It helps us understand why plants are so vitally important to the world. Plan...

Botany for Pre- Medicine students. Dr: M. A. Al-Ryani. Introduction In General Botany Botany is the scientific study of plants and plant-like organisms. It helps us understand why plants are so vitally important to the world. Plants start the majority of food and energy chains, they provide us with oxygen, food and medicine. Botany: also called plant science(s), plant biology or phytology, is the science of plant life and a branch of biology. A botanist or plant scientist: is a scientist who specializes in this field. The term "botany": comes from the Ancient Greek word βοτάνη (botanē) meaning "pasture", (‫")أعشاب المراعي‬grass", or "fodder"(‫;)أعﻼف الحيوانات الجافة‬ βοτάνη is in turn derived from βόσκειν (boskein), "to feed" or "to graze".(‫)تغذي الحيوان أو الرعي‬ Traditionally, botany has also included the study of fungi and algae by mycologists and phycologists respectively, with the study of these three groups of organisms remaining within the sphere of interest of the International Botanical Congress. Nowadays, botanists (in the strict sense ‫)بتحديد دقيق‬ study approximately 410,000 species of land plants of which some 391,000 species are vascular plants (including 369,000 species of flowering plants), and 20,000 are bryophytes. (‫)حزازيات‬ Botany originated: In prehistory as herbalism with the efforts of early humans to identify and later cultivate edible medicinal and poisonous plants, making it one of the oldest branches of science. ‫ السامة منها مما جعل من علم‬،‫ العﻼج‬،‫)اﻹنسان القديم بدل مجهود للتعرف على النباتات وزراعتها لغرض اﻷكل‬ ,(‫النبات أقدم فروع العلوم‬ Medieval physic gardens (‫)التداوي باﻷعشاب في العصور الوسطى‬, contained plants of medical importance. They were forerunners of the first botanical gardens attached to universities, founded from the 1540s onwards. One of the earliest was the Padua botanical garden. These gardens facilitated the 1 Botany for Pre- Medicine students. Dr: M. A. Al-Ryani. academic study of plants. Efforts to catalogue and describe their collections were the beings of plant taxonomy, and led in 1753 to the binomial system of Carl Linnaeus that remains in use to this day. In the 19th and 20th centuries, new techniques were developed for the study of plants, including methods of optical microscopy and live cell imaging, electron microscopy, analysis of chromosome number, plant chemistry and the structure and function of enzymes and other proteins. In the last two decades of the 20th century, botanists exploited the techniques of molecular genetic analysis, including genomics and proteomics and DNA sequences to classify plants more accurately. Modern botany: is a broad multidisciplinary (‫ )متعدد اﻷنظمة‬subject with inputs from most other areas of science and technology. Research topics include the study of plant structure, growth and differentiation, reproduction, biochemistry and primary metabolism, chemical products, development, diseases, evolutionary relationships, systematic, and plant taxonomy. Dominant themes in 21st century: plant science are molecular genetics and epigenetics, which are the mechanisms and control of gene expression during differentiation of plant cells and tissues. Botanical research has diverse applications in providing staple foods, materials such as timber, oil, rubber, fiber and drugs, in modern horticulture, agriculture and forestry, plant propagation, breeding and genetic modification, in the synthesis of chemicals and raw materials for construction and energy production, in environmental management, and the maintenance of biodiversity. 2 Botany for Pre- Medicine students. Dr: M. A. Al-Ryani. ،‫ المطاط‬،‫ الزيوت‬،‫ أﻵمن الغذائي وتوفير الغذاء اﻹنتاج الصناعي)الخشب‬:‫البحوث النباتية لها تطبيقات مختلفة‬ ‫الخ( في العلم الحديث لعلوم البستنة والزراعة والغابات وتكاثر النباتات وعلوم الوراثة‬...‫ الدواء‬،‫اﻷنسجة‬ ‫ وكذلك في علوم البيئة والمحافظة على التنوع‬،‫ أنتاج الطاقة بالبناء الكيميائي للمواد الخام‬،‫والتحويرات الوراثية‬.‫الحيوي‬ The study of plants is vital because they underpin almost all animal life on Earth by generating a large proportion of the oxygen and food that provide humans and other organisms with aerobic respiration with the chemical energy they need to exist. Plants, algae and cyanobacteria are the major groups of organisms that carry out photosynthesis, a process that uses the energy of sunlight to convert water and carbon dioxide into sugars that can be used both as a source of chemical energy and of organic molecules that are used in the structural components of cells. As a by-product of photosynthesis, plants release oxygen into the atmosphere, a gas that is required by nearly all living things to carry out cellular respiration. In addition, they are influential in the global carbon and water cycles and plant roots bind and Stabilize soils, preventing soil erosion. Plants are crucial to the future of human society as they provide food, oxygen, medicine, and products for people, as well as creating and preserving soil. ‫ النباتات فاصل حاسم‬،‫باﻹﺿافة إلى دورة الكربون و الماء في الطبيعة الجذور تثبت التربة وتحميها من التعرية‬ ‫ وكذلك‬،‫لمظاهر المجتمعات اﻹنسانية ﻷنها المصدر الرئيس الممد بالغذاء واﻻكسجين والدواء والمنتجات اﻷخرى‬.‫تنشئ وتحمي التربة‬ Historically, all living things were classified as either animals or plants and botany covered the study of all organisms not considered animals. Botanists examine both the internal functions and processes within plant organelles, cells, tissues, whole plants, plant populations and 3 Botany for Pre- Medicine students. Dr: M. A. Al-Ryani. plant communities. At each of these levels, a botanist may be concerned with the classification (taxonomy), phylogeny and evolution, structure (anatomy and morphology), or function (physiology) of plant life. The strictest definition (‫)التعريف الدقيق‬of "plant" includes only the "land plants" or embryophytes, which include seed plants (gymnosperms, including the pines, and flowering plants) and the free-sporing cryptogams including ferns‫سرخس‬, clubmosses ‫الحزازيات الورقية‬, liverworts ‫الكبديات‬, hornworts and mosses‫والحزازيات‬ ‫اﻻعشاب القرنية‬. Embryophytes are multicellular eukaryotes descended from an ancestor that obtained its energy from sunlight by photosynthesis. They have life cycles with alternating haploid and diploid phases. The sexual haploid phase of embryophytes, known as the gametophyte, nurtures the developing diploid embryo sporophyte within its tissues for at least part of its life, even in the seed plants, where the gametophyte itself is nurtured by its parent sporophyte. Other groups of organisms that were previously studied by botanists include bacteria (now studied in bacteriology), fungi (mycology) including lichen-forming fungi (lichenology), non-chlorophyte algae (phycology), and viruses (virology). However, attention is still given to these groups by botanists, and fungi (including lichens) and photosynthetic protists are usually covered in introductory botany courses. Palaeobotanists; study ancient plants in the fossil record to provide information about the evolutionary history of plants. Cyanobacteria, the first oxygen-releasing photosynthetic organisms on Earth, are thought to have given rise to the ancestor of plants by entering into an endosymbiotic relationship with an early eukaryote, ultimately becoming the chloroplasts in plant cells. The new photosynthetic plants (along with their algal relatives) accelerated the rise in atmospheric oxygen started by the cyanobacteria, changing the ancient oxygen-free, 4  Botany for Pre- Medicine students. Dr: M. A. Al-Ryani. reducing, atmosphere to one in which free oxygen has been abundant for more than 2 billion years. Among the important botanical questions of the 21st century are the role of plants as primary producers in the global cycling of life's basic ingredients: energy, carbon, oxygen, nitrogen and water, and ways that our plant stewardship can help address the global environmental issues of resource management, conservation, human food security, biologically invasive organisms, carbon sequestration, climate change, and sustainability. Plant Classification: Table(1): Major Schemes of Classifications of Living Organisms: Classification Scheme Kingdoms Organisms included Plantae Bacteria, Fungi, Alagae, plants. Linnaeus (1754) Animalia Protozoa and higher animals. Plantae Multicellular algae and plants Animalia Animals Haeckel (1866) Microorganisms, including bacteria, Protista protozoa, algae, molds, and yeasts. Plantae Multicellular algae and plants Animalia Animals Whittaker (1969) Protista Protozoa and single Oiled algae. Fungi Molds and yeasts Monera All bacteria (Prokaryotes). Bacteria that produce methane gas, Archaeo- require very high levels of salts, of bacteria require very high temperatures. All other bacteria including those Wosese (1977) inmost familiar to microbiologists, Eubacteria such as disease causing bacteria, and photosynthetic bacteria. Protozoa, algae, fungi, plants, and Eucaryota animals. 5 Botany for Pre- Medicine students. Dr: M. A. Al-Ryani. Classical classification of Plantae (Ishler,1883): :(‫م‬1883) ‫التقسيم التقليدي القديم للمملكة النباتية أيشلر‬ 1- Cryptogamae; a-Thallophyta: Unicellular or sample structure (Thallus), without phloem and xylem tissues, usually undifferentiating into special organs such as branching, roots and leaves. Reproduction by microscopic reproductive unit called spores (eg; bacteria, algae, fungi (yeast and molds) and lichens). b-Bryophyta; Pro-plants small in size. Autotrophic (Phototrophic), body structure composed from simple leaves, rhizoids and seta (eg; Mosses). 2- Vascular plants; Composed from transporting vascular system. Differentiating into leafs, steams and roots. Divided into; a-Pteridophyta (lower vascular plants); Non-sperm formation produce spores(eg; ferns). b-Spermatophyta (Higher vascular plants); seed plants, classified into; 1-Gymnosperm (eg; pinus threes). 2-Angiosperms flowering plants (Monocot and Dicot). :Cryptogamae ‫ النباتات عديمة اﻹزهار‬-ً‫أوﻻ‬ 60 ‫ وتشمل البكتيريا و الطحالب و الفطريات تظم‬Thallophyta ‫ النباتات الثالوسية‬-1.‫ألف نوع من النباتات‬.‫ ألف نوع نباتي‬20 ‫ بها ما يقرب عن‬Bryophyta ‫ النباتات الحزازية‬-2.‫ اﻻف نوع نباتي‬10 ‫ تظم حوالي‬Pteridophta ‫ النباتات السرخسية‬-3 :Phanerogamae ‫ النباتات الزهرية‬-ً ‫ﺛانيا‬ 6  Botany for Pre- Medicine students. Dr: M. A. Al-Ryani. ‫ وتشمل؛‬Speratophyta ‫ النباتات البذرية‬-4.‫ نوع نباتي‬500 :Gymnospermae ‫ النباتات معراة البذور‬-‫أ‬ ‫ ألف نوع نباتي وهي السائدة‬200 ‫حوالي‬Angiospermae ‫ النباتات مغطاة البذور‬-‫ب‬ ‫ وتنقسم إلي مجموعتين؛‬،‫اﻵن على وجه اﻷرض‬ ‫ لها ورقة جنينية واحدة داخل البذرة مثل‬:‫ ذوات الفلقة الواحدة‬Monocotes-1.‫النجيليات كالقمح والشعير والذرة‬ ‫ لها وريقتين جنينيتين داخل البذرة تظم أغلب النباتات‬:‫ ذوات الفلقتين‬Dicotes-2.‫عريضة اﻷوراق بما فيها أشجار الثمار وأغلب نباتات الخضروات‬ Fields of Botany: A) Descriptive fields: Plant taxonomy, anatomy, morphology, cytology. B) Experimental fields: plant physiology, plant genetics, plant ecology, biotechnology (genetic engineering). Nomenclature the Names of Plants: 1- Common Names. ‫ حتى في اللغة‬،‫لكل لغة أسماء عامة أو شائعة ﻻي نبات وهذه اﻷسماء تختلف بين اللغات المختلفة‬.‫الواحدة يمكن أن تجد أسماء دارجة مختلفة لنفس النبات‬ 2- Scientific Names. ‫ وبسبب أن‬،‫أسماء يمكن معرف لكل المتخصصين في كل البلدان وتكون أسماء واحدة لكل نوع نباتي‬ ‫لغة المتخصصين فيما بين القرن السادس و السابع عشر كانت اللغة الﻼتينية لذلك كتبت اﻷسماء‬.‫بالﻼتيني‬ Binomial System of Name: (Carl Linnaeus 1753) Binomial nomenclature (also called binominal nomenclature or binary nomenclature) is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, although they can be based on words from other languages. Such a name is called a binomial name (which may be shortened to just "binomial"), a binomen, binominal name or a scientific name; more informally it is also called a Latin name. The first part of the name identifies the genus to which the species belongs; the 7 Botany for Pre- Medicine students. Dr: M. A. Al-Ryani. second part identifies the species within the genus. For example, humans belong to the genus Homo and within this genus to the species Homo sapiens. The formal introduction of this system of naming species is credited to Carl Linnaeus, effectively beginning with his work Species Plantarum in 1753. But Gaspard Bauhin, in as early as 1623, had introduced in his book Pinaxtheatri botanici (English, Illustrated exposition of plants) many names of genera that were later adopted by Linnaeus. The application of binomial nomenclature is now governed by various internationally agreed codes of rules, of which the two most important are the International Code of Zoological Nomenclature (ICZN) for animals and the International Code of Nomenclature for algae, fungi, and plants (ICN). Although the general principles underlying binomial nomenclature are common to these two codes, there are some differences, both in the terminology they use and in their precise rules. In modern usage, the first letter of the first part of the name, the genus, is always capitalized in writing, while that of the second part is not, even when derived from a proper noun such as the name of a person or place. Similarly, both parts are italicized when a binomial name occurs in normal text. Thus the binomial name of the annual phlox (named after botanist Thomas Drummond) is now written as Phlox drummondii. In scientific works, the "authority" for a binomial name is usually given, at least when it is first mentioned, and the date of publication may be specified. ‫ والمقطع‬Genus ‫ كل نوع نباتي له أسم علمي ﻻتيني يتكون من مقطعين المقطع اﻷول أسم جنس‬.Species ‫الثاني نوع‬.Capitlized ‫ أسم الجنس يكتب أوله بحرف كبير‬.Small ‫ مقطع النوع ؤيتبع أسم الجنس ويكتب بحروف صغيرة‬ ‫ صفة لنباتً أو‬،‫ مقطع الجنس يمكن اشتقاقه من أي مصدر أو كلمة تعامل ﻻتينيا؛ كاسم تكريم لعالم‬.‫أسم دارج قديم‬ ‫ ربما يشير إلي موقع جغرافي‬،albo ‫ مقطع النوع يمكن أن يشتق من صفة معينة للنبات مثل أبيض‬.‫أو أسم عالم‬ A. niger ‫ أسم الجنس يمكن اختصاره عند كثابتة أكثر من مرة في موضوع معين مثل‬ 8  Botany for Pre- Medicine students. Dr: M. A. Al-Ryani. ‫ و أذا كان أكثر من نوع يكتب‬sp. ‫ عندما ﻻ يريد أن يشير الكاتب إلي أسم النوع أو ﻻ يعرفه يكتب‬.‫ قاﺋم‬spp..‫ يلحق بالسم العلمي اسم العالم الذي أطلق اﻻسم على النبات ﻷول مرة‬ International ‫ كل هذه القواعد موضوعة في قانون يسمى القانون الدولي للتسمية النباتية‬ Code of Botanical Namenclature(ICBN)..aceae ‫ ينتهي أسم الفصيلة بمقطع‬Family ‫ تنظم اﻷنواع واﻷجناس النباتية تحث فصاﺋل‬.ales ‫ تنتهي الرتبة بمقطع‬Order ‫ كل فصيلة تندرج تحت رتبة‬.opsida ‫ تنتهي بمقطع‬Class ‫ كل رتبة تندرج تحت طاﺋفة‬.phyta ‫ التي تنتهي بالمقطع‬Division ‫ كل الرتب تنظم تحت أقسامها‬ Cell Theory: The term cell is derived from the Latin ‘cella’ means storeroom or chamber. The term cell was first used by the English botanist Robert Hooke in 1665, to describe the individual units of the honeycomb-like structure in cork under compound microscope. Cell Theory, which recognizes the cell as the basic unit of life. The Cell Theory further states that all organisms are composed of cells and all cells arise from preexisting cells. This theory is one of the major principles in biology. However the biggest division is between the cell of the prokaryotic Kingdom (Bacteria) and those of the other (Animals, Plants, Fungi, and protoctista), which are all eukaryotic cells. Procaryotic cells are smaller and simpler than eukaryotic cells, and not have a true nucleus. Summary of the Differences Between Pro and Eu-karyotic cells; Prokaryotic cells Eukaryotic cells Small cells less than( 10μm) Always unicellular. Often multicellar Without nucleus and any membrane-bound Always have and other membrane-bound organelles, such as mitochondria organelles DNA is circular, without protein DNA is linear and associated with protins to form chromatin. Ribosomes are small(70S) Ribosomes are large(80S) No cytokeleton Always has cyt4oskeleton. Motility by rigid rotating flagellum made of By flexible waving cilia or flagellae made flagellin. of tubulin. Cell division by binary fission By mitosis or meiosis. Reproduction is always by asexual. Asexual or sexual. 9