BIOL1010-1011-F2017-L2-Intro to Cells-posted

BIOL1010 - Biology 1: Molecular and Cellular Systems BIOL1011 - Introductory Cell and Molecular Biology LECTURE 2 INTRODUCTION TO CELLS What is Biology? What are the Properties of Living Organisms? What does Evolution Explain? What are Cells? What are Prokaryotic Cells? What are Eukaryotic Cells? © 2017 by M.Olaveson-UOIT 1 Biologists closer to understanding: how a single cell develops into an organism how plants convert sunlight to chemical energy how human mind works how living organisms interact how life’s diversity evolved from early microbes What is Biology? Scientific study of life and how it works NOW is Biology’s most exciting period ever! © 2017 by M.Olaveson-UOIT 2 What is Life? What makes something alive? What is Biology? © 2017 by M.Olaveson-UOIT 3 1. Consists of organized cells (for order and complexity) 3. Shows growth (and development) 6. Responds to environmental stimuli (with reaction to change) Figure 1.2 from Campbell and Reese (2005) 2. Contains heritable genetic information (for reproduction) 4. Uses/converts energy and matter for biological function (in metabolism) What are the Properties of Living Organisms? 7. Adapts to environmental change (with evolution through natural selection) 5. Maintains homeostasis (through regulation) © 2017 by M.Olaveson-UOIT 4 All Living Organisms adapt to Environmental Changes (by Evolution through Natural Selection) A) Diversity of Life - through Evolution All organisms are capable of reproduction involving duplication of genetic material with potential for errors to occur Leads to differences among organisms that enable them - to live in different kinds of environments - to adapt to changing environmental conditions Modern Biology uses Charles Darwin’s Theory of Evolution through Natural Selection (1859) as a unifying framework Diversity / Unity of Life explained by Evolution What does Evolution Explain? © 2017 by M.Olaveson-UOIT 5 Diversity of Life What does Evolution Explain? © 2017 by M.Olaveson-UOIT 6 Figure 1.10 from Purves et al. (2001) 6 Kingdoms Modern biological classification of organisms in based on: 1. obvious similarities 2. evolutionary relationships 3 Domains General agreement on highest level of classification All organisms can be grouped into one of 3 Domains What does Evolution Explain? Recent molecular research suggests there are 7 distinct groups (super-kingdoms) within Domain Eukarya © 2017 by M.Olaveson-UOIT 7 7 Super-Kingdoms 27 Kingdoms Modern biological classification of eukaryotic organisms has been revised using evolutionary relationships based on molecular evidence Figure 27.9 from Morris et al. (2013) What does Evolution Explain? © 2017 by M.Olaveson-UOIT 8 As diverse as life is - evidence of remarkable unity based on aqueous (= water) solutions consist of 6 elements (C, H, N, O, P and S) similar macromolecules (carbohydrates , lipids, proteins) have RNA and DNA from same nucleotides genome composed of RNA or DNA (replication) have ribosomes acting as sites of protein synthesis undergo rapid metabolic reactions catalyzed by proteins osmotically active membranes of similar structure use formation / hydrolysis of ATP for energy flow cellular B) Unity of Life - through Evolution Diversity / Unity of Life explained by Evolution What does Evolution Explain? © 2017 by M.Olaveson-UOIT 9 All living organisms consist of cells that: are structural compartments have an internal environment separated from the external environment by a membrane use macromolecules to perform unique functions (e.g. metabolism, reproduction) Current Cell Theory states that: cells are the basic units of life all organisms are composed of cells all cells come from pre-existing cells What are Cells? © 2017 by M.Olaveson-UOIT 10 Properties of Cells: The three most important distinguishing features of life on Earth as exhibited by all cells are: cells can store and transmit information cells have a plasma membrane cells can harness energy from the environment What are Cells? © 2017 by M.Olaveson-UOIT 11 Figure 1.10 from Purves et al. (2001) 6 Kingdoms Cells are classified into 2 types based on internal structure 3 Domains prokaryotes eukaryotes Cell Types What are Cells? © 2017 by M.Olaveson-UOIT 12 Prokaryotic – lack membrane-enclosed organelles Eukaryotic – have membrane-enclosed organelles Types of Cells: Figure 5.16 from Morris et al. (2016) What are Cells? © 2017 by M.Olaveson-UOIT 13 lack internal membrane- bound organelles genetic material loosely organized in nucleoid regions in cytoplasm have plasma membrane and ribosomes has cell wall for support Figure 4.4 from Purves et al. (2001) prokaryotes are small (< 10 mm) Figure 26.3 from Purves et al. (2001) What are Prokaryotic Cells? © 2017 by M.Olaveson-UOIT 14 have internal membrane-bound organelles e.g. nucleus, ER, GA, chloroplasts, mitochondria, vacuoles, lysosomes have a plasma membrane have external cell wall or internal cytoskeleton for support Figure 4.7 from Purves et al. (2001) Plant Cell Animal Cell eukaryotes are larger than prokaryotes (> 10 mm) What are Eukaryotic Cells? © 2017 by M.Olaveson-UOIT 15 Eukaryotic Organelles (LEARN THESE STRUCTURES) {5C22544A-7EE6-4342-B048-85BDC9FD1C3A}ORGANELLE STRUCTURE FUNCTION ROLE cell wall chloroplast cytoskeleton endoplasmic reticulum (ER) extracellular matrix (ECM) Golgi apparatus (GA) lysosome mitochondrion nucleolus nucleus ribosome vacuole © 2017 by M.Olaveson-UOIT 16 What type of cell is shown below? What are Cells? © 2017 by M.Olaveson-UOIT 17 Any Questions ? © 2017 by M.Olaveson-UOIT 18