Transcript “cells”.
INTRODUCTION TO CELLS Robert Hooke naturalist, philosopher, inventor, architect.... (July 18, 1635 - March 3, 1703) In 1665 Robert Hooke publishes his book, Micrographia, which contains his drawings of sections of cork as seen through one of the first microscopes (shown at right). He was the first person to use the term “cells”. Anton van Leeuwenhoek 1632-1723 In 1673 Anton van Leeuwenhook perfects the simple microscope and observes cells and microorganisms. He discovered bacteria in 1674 and four years later, he discovers protozoa. Cell Theory Matthias Schleiden concluded that all plants are made of cells (1838) Theodore Schwann concluded that all animals are made of cells (1839) Rudolf Virchow concluded that all cells came from pre-existing cells (1855) Cell Theory • all living things are made up of cells • cells are the basic units of structure and function in an organism • new cells are produced from existing cells Cell Specialization Cells in organisms are specialized to perform different tasks. Photos from Biology, Prentice Hall The Levels of Organization Multicellular organisms are arranged from simple to complex according to their level of cellular grouping. cell tissue organ organ system organism Cell Types PROKARYOTE EUKARYOTE No nucleus No membrane-bound organelles Small ribosomes Most cells are 1 -10 μm in size Evolved 3.5 billion years ago Found only in Archaebacteria and Eubacteria Kingdoms Has nucleus Many organelles Larger ribosomes Cells can be between 2 - 1,000 μm in size Evolved 1.5 billion years ago Includes Protista, Fungi, Plantae and Animalia Kingdoms Cell Type: Prokaryotes Prokaryotes, which includes all bacteria, are the simplest cellular organisms. They have genetic material but no nucleus. Typical bacteria cell Cell Types: Eukaryotes Eukaryotic cells contain a membranebound nucleus and numerous membrane -enclosed organelles (e.g., mitochondria, lysosomes, Golgi apparatus) not found in prokaryotes. Different Types of Cells Prokaryotic no nucleus Eukaryotic nonucleus nucleus nucleus small ribosomes larger ribosomes larger ribosomes small ribosomes no organelles noorganelles organelles small small very small 1-10m very organelles small 2-1000m only in bacteria protists, fungi, protists, fungi, only in bacteria plants, animals plants, animals What Are the Parts of Cells Both prokaryotic and eukaryotic cells have some things in common. nuclear cell membrane ribosomes cytoplasm material All cells have ¤ cell membrane ¤ cytoplasm ¤ ribosomes ¤ nuclear material cytoplasm: nucleus: chloroplast: vacuole: ribosomes: mitochondria: cell membrane: wall: sac-like controls outer semi-liquid manufacture capture convert layer most in material cell energy structure proteins chemical regulates plant processes, cells, from that energy that what support sunlight fills stores enters contains stored theand cell hereditary water, in and protection food convert leaves salts, intoinformation the ATP it foods, into cell, (cellular etc (DNA) chemical respiration protection energy and occurs support (food), here) (photosynthesis occurs here) Parts of Cells cytoplasm nucleus chloroplast vacuole ribosomes mitochondria cell membrane (p. 175) cell wall Parts of Cells cell membrane mitochondria ribosome Golgi apparatus nucleus cytoplasm Endoplasmic reticulum lysosome lysosome: Golgi apparatus: digests lipids, Endoplasmic reticulum: modifies, carbohydrates, site wheresorts lipid and packages proteins into proteins small components of the and cell other molecules materials that frombethe membrane are can endoplasmic used by the along rest reticulum ofwith the assembled, for cell; storage alsoand involved inother the cell in or proteins secretion breaking outside materialsdown that are the cell organelles thatthe have exported from cell outlived their usefulness Cell Organelles Cell Membrane Mitochondria Chloroplast Endoplasmic Reticulum Nucleus Vacuole Lysosome Golgi Body Ribosome Animal Cell Wall Plant