Lecture 2: Botany as a Science PDF

Lecture 2: Botany as a Science Study of Plants Greek words  Botanikos (botanical)  Botane (plant or herb)  Boskein (to feed)  Origin: Stone Age  Focus: Utilitarian values of plants  Intellectual interests arose ...

Lecture 2: Botany as a Science Study of Plants Greek words  Botanikos (botanical)  Botane (plant or herb)  Boskein (to feed)  Origin: Stone Age  Focus: Utilitarian values of plants  Intellectual interests arose History of Botany – A Timeline Early studies 4th Century Both B.C.: Aristotle and got involved Theophrastus in identifying plants and describing them. Theophrastus was hailed as the “Father of botany” because of his two surviving works on plant studies. Although Aristotle also wroteabout plants,  In A.D. 60: Dioscorides wrote De Materia Medica This work described a thousand medicines, majority of which came from plants. For 1500 years, it remained the guidebook on medicines in the Western world until the invention of the compound microscope. Quote: “Medicine sometimes grants health, sometimes destroys it, showing which plants are helpful, which do harm.” Early 17th century: For a brief period, the search for knowledge in the field of Botany temporarily became stagnant. However, the revival of learning during the European Renaissance renewed interest in plants. The number of scientific publications increased. Herbalism – Medicine – Plant Science 1640: Johannes van Helmont measured the uptake of water in a tree (Weight of the tree) 1665: Robert Hooke invented the microscope. His description of these cells was published in Micrographia. However, the cells seen by Hooke showed no signs of the nucleus and other organelles found in most living cells 1674: Anton van Leeuwenhoek saw a live cell under a microscope. Before his discovery, the existence of single- celled organisms were unknown and initially were met with skepticism. 1686: John Ray published his book, Historia Plantarum. This became an important step towards modern taxonomy (Arber 2010). 1694 : Rudolf Camerarius established plant sexuality in his book entitled De Sexu Plantarum Epistola. There, he stated that: “No ovules of plants could ever develop into seeds from the female style and ovary without first being prepared by the pollen from the stamens, the male sexual organs of the plant”.  During the 18th Century 1727 : Stephen Hales successfully established plant physiology as a science. He published his experiments with dealing nutrition and respiration the of plants publication entitled in his Vegetable statiks. He developed techniques to measure area, mass, volume, temperature, pressure, and even gravity in plants. 1758: Carolus Linnaeus (Carl von Linne), the “Father of Taxonomy“, introduced the science of taxonomy which deals with the identification, nomenclature, description and classification of organisms (species). 1760s: Botan became even more widespread y educated among women painte plants attende classes who on plant d , d classification, herbarium specimens. and collecte d Later part of the eighteenth century: Joseph Priestley laid the foundation for the chemical analysis of plant metabolism.  Joseph Priestley published his works as Experimental and Observations on Different Kinds of Air in 1774. The published paper demonstrated that green plants absorb “fixed air” (carbon dioxide) from the atmosphere, give off “gas” or “dephlogisticated air”, which is now known as oxygen, and that this gas is essential to animal life  During the 19th Century Early part of the nineteenth century: Progress in the study of plant fossils was made. 1818: Chlorophyll was discovered by Joseph Caventou 1840: Advances were made in the study of disease because of the potato blight that plant potats crop killed in Ireland. This led to the further o s study diseases of plan t 1847: The process of photosynthesis was first elucidated by Mayer. However, the exact and detailed mechanism remained a mystery until the 1862. 1859: Charles Darwin proposed his theory of adaptation, or more commonly referred evolution “survival to as and of the fittest” (kenyon.edu 2016). Charles Darwin and Alfred Russel Wallace collaborated. Darwin soon published his renowned and highly recognized book On the origin of species by means of natural selection 1862 The exact mechanism of photosynthesis : was discovered when it was observed that starch was formed in green cells only in the presence of light. 1865: The results of Mendel’s experiments in showe tha 1865 both parents should pass distinct d t code information to their physical offspring factor at whic conception. The offspring then inheritsone s unit h for each trait from each of his parents  Twentieth Century up to the Present Early 20th Century: The process of nitrogen fixation, nitrification, and ammonification was discovered. 1903: The two types of chlorophyll—a and b were 1936: discovered. Through his experiment, Alexander Oparin demonstrated the mechanism of the synthesis of organic matter from inorganic molecules. 1940s: Ecology became a separate discipline. Technology has helped specialists in botany to see and understand the three- dimensional nature of cells, and genetic engineering of plants. This had greatly improved agricultural crops and products Botany as a Science Follows Scientific Procedure aka Scientific Method (SM) Systematic, organized, logical Diversificati on of Plant Study Citizen or Community Science scientific work undertaken by members of the general public.  collaboration with or under the direction of professional scientists and scientific institutions Group Work  Discuss with your group and develop a problem based on your observations about a plant or group of plants  Use the SM to lay down the steps you are going to take to try to solve or answer your problem  Answer the following questions 1.What are your observations? 2.What are your hypothesis? 3.How will you test your hypothesis? 4.What can be your predictions based on 3?