2022/2023 CHS IP Biology Notes(Y3-Y4)

Year 3 / Cell Structure & Organisation Teacher’s Copy Prepared by: Jeffrey Goh Last updated by: Jeffrey Goh on 30 Nov 2021 Page 1 Catholic High School Integrated Programme Year 3 Biology Lecture Notes 01 – Cell Structure & Organisation Name: Class: A. Content • Plant and animal cells • Specialised cells, tissues and organs B. Learning Outcomes Students should be able to: (a) identify cell structures (including organelles) of typical plant and animal cells from diagrams, photomicrographs and as seen under the light microscope using prepared slides and fresh material treated with an appropriate temporary staining technique: • chloroplasts • cell membrane • cell wall • cytoplasm • cell vacuoles (large, sap-filled in plant cells, small, temporary in animal cells) • nucleus (b) identify the following membrane systems and organelles from diagrams and electron micrographs: • endoplasmic reticulum • mitochondria • Golgi body • ribosomes (c) state the functions of the membrane systems and organelles identified above. (d) compare the structure of typical animal and plant cells. (e) state, in simple terms, the relationship between cell function and cell structure for the following: • absorption – root hair cells • conduction and support – xylem vessels • transport of oxygen – red blood cells (f) differentiate cell, tissue, organ and organ system. C. References 1. Clegg, C. J. and Mackean, D. G. Advanced Biology: Principles and Applications (2nd ed). John Murray (Publishers) Ltd. 2. Lam, P. K. and Lam, E. Y. K. GCE ‘O’ Level: Biology Matters (2nd ed). Marshall Cavendish Education. 3. Mackean, D. G. GCSE Biology (3rd ed). John Murray (Publishers) Ltd. 4. Miller, K. R. and Levine, J. Biology. Pearson Prentice Hall. 5. Reece, J. B., Urry, L. A., Cain, M. L., Wasserman, S. A., Minorsky, P. V. and Jackson, R. B. Campbell Biology (9th ed). The Benjamin/Cummings Publishing Company, Inc. D. Lecture Outline 1. Introduction 2. Historical perspectives 3. Cell structure 4. Cell differentiation E. Practical Work • Preparing, observing and drawing plant cells

Year 3 / Cell Structure & Organisation Teacher’s Copy Prepared by: Jeffrey Goh Last updated by: Jeffrey Goh on 30 Nov 2021 Page 2 1. INTRODUCTION The cell is the basic unit of life from which organisms are made. Cells are microscopic and can only be seen through the magnifying lenses of a microscope. In 1665, Englishman Robert Hooke published his book Micrographia, which contains drawings of thin slices of cork seen through a microscope. Anthony Van Leeuwenhoek (pronounced ‘Laywenhook’) was one of the very first to produce detailed observations of plant and animal cells with his self -made microscope. The study of the structure of cells (cytology) is a major branch of cell biology. Figure 1.1 A Leeuwenhoek microscope can magnify x266 Source: http://sciencesanneehuit.wikispaces.com/Microscope+simple 1 centimeter (cm) = 10-2 meter (m) 1 millimeter (mm) = 10-3 meter (m) 1 micrometer (µm) = 10-3 mm = 10-6 m Figure 1.2 The size range of cells Source: Pearson Education In the 1950s, all living organisms were placed in 5 kingdoms: Monera, Protista, Fungi, Plantae and Animalia. As recent as the 1990s, kingdom Monera was recognised as two different kingdoms (Eubacteria and Archaebacteria) as a result of accumulating molecular evidence. Today, as a result of molecular analyses, scientists recognise the classification of living organisms into three domains: Eukarya (composed of protists, fungi, plants and animals), Bacteria and Archaea. Figure 1.3 Phylogenetic tree supporting the grouping of organisms into three domains

Year 3 / Cell Structure & Organisation Teacher’s Copy Prepared by: Jeffrey Goh Last updated by: Jeffrey Goh on 30 Nov 2021 Page 3 Members of the domain Archaea live in some of the most extreme environments on the planet. Th ese include thermophilic bacteria and halophilic bacteria. The members of the domain Bacteria are ecological diverse bacteria whose cell wall contains a substance known as peptidoglycan. Table 1.1 Organisms are grouped into three domains Classification of Living Things DOMAIN Bacteria Archaea Eukarya KINGDOM Eubacteria Archaebacteria Protista Fungi Plantae Animalia CELL TYPE Prokaryote Prokaryote Eukaryote Eukaryote Eukaryote Eukaryote CELL STRUCTURES Cell walls with peptidoglycan Cell walls without peptidoglycan Cell walls of cellulose in some, some have chloroplasts Cell walls of chitin Cell walls of cellulose; chloroplasts No cell walls or chloroplasts NUMBER OF CELLS Unicellular Unicellular Most unicellular; some colonial; some multicellular Most multicellular; some unicellular Multicellular Multicellular MODE OF NUTRITION Autotroph or heterotroph Autotroph or heterotroph Autotroph or heterotroph Heterotroph Autotroph Heterotroph EXAMPLES Streptococcus, Escherichia coli Methanogens, halophiles Amoeba, Paramecium, slime molds, giant kelps Mushrooms, yeasts Mosses, ferns, flowering plants Sponges, worms, insects, fishes, mammals Miller and Levine 2. HISTORICAL PERSPECTIVES Table 1.2 Key steps in the origins of cell biology Since antiquity Magnifying properties of convex lens known 1839 Purkinje Realised that the contents of cells (‘cytoplasm + nucleus’) were important, not just the walls Early 17th century The use of two convex lenses to make near objects look larger was practised in Europe 1838 Matthias Schleiden Explained the derivation of plant tissues from cells 1632–1723 Antony van Leeuwenwoek produced his own microscopes and made numerous observations of blood cells and protozoa 1839 Theodor Schwann ‘Cells are organisms and entire animals and plants are aggregates of these organisms arranged according to definite laws’ 1661 Marcello Malpighi Used lenses, discovered capillaries, and may have described cells in writing of ‘saccules’ and ‘globules’ 1856 Rudolf Virchow Established the idea that cells arise only by division of existing cells 1662 Robert Hooke Introduced the term ‘cell’ in describing the structure of cork; believed cell walls to be the important part of otherwise empty structures 1862 Louis Pasteur Disposed of the spontaneous generation theory of microbial appearance 1809 Jean de Monet de Lamarck ‘No body can possess life if its containing parts are not of cellular tissue or formed by cellular tissues’ 1897 Eduard Buchner Confirmed that fermentation requires only a cell extract, not whole cells 1825–1945 With the invention of the immersion lens, the light microscope reached the limit of resolving power = 0.2 µm 1900 Rediscovery of work of Gregor Mendel, giving the theoretical basis of modern genetics

Year 3 / Cell Structure & Organisation Teacher’s Copy Prepared by: Jeffrey Goh Last updated by: Jeffrey Goh on 30 Nov 2021 Page 4 1828 Friedrich Wöhler Synthesised urea, discrediting the view that organic compounds can be made only by living things 1930–46 Electron microscope developed, then used widely in cytology, revealing details of cell organelles (cell ultrastructures) 1831 Robert Brown Reported his discovery of the cell nucleus modern cell biology Established that cells contain basic hereditary material (DNA) in the nucleus; roles of nucleic acid in the control of metabolism and of growth via protein synthesis understood Clegg and Mackean 3. CELL STRUCTURE A cell is a unit of life consisting of a mass of living matter called protoplasm. A cell functions just like a factory with many specialized organs known as organelles. A cell can be divided into 2 main regions: the nucleus and the cytoplasm. All cells have cytoplasm surrou