CELLS - Thexgene.weebly
CELLSSTRUCTURE AND FUNCTIONJhia Anjela D. RiveraDepartment of Biological SciencesSchool of Science and TechnologyCentro Escolar University
DISCOVERY OF CELLS Robert Hooke (1665): Observed a thin slice of cork with a microscope Coined the word cells Antonie Philips van Leeuwenhoek (1675): Inventor of compound microscope First person to observe living cells: first to publish descriptions of somemicroscopic entities such as single-celled organisms, muscle cells,spermatozoa, capillaries, etc.
CELL THEORY Concluded by Schleiden (1838), Schwann (1839) and Virchow (1858) Matthias Schleiden Concluded that all plants are composed of cells Theodor Schwann Concluded that all animals are made of cells Rudolf Ludwig Karl Virchow Concluded that all organisms are composed of cells and that cells originateonly from preexisting cells, and not from inanimate matter
CELL THEORY All living things are composed of one or more cells. Cells are organisms’ basic units of structure and function Cells come only from preexisting cells “All organisms are made up of one or more cells, within which the life process ofmetabolism and heredity occur.”
PROKARYOTES vs. EUKARYOTESPROKARYOTESEUKARYOTESDEFINITIONResemble one another in form, havelittle internal organization, strong cellwall that encloses themHave more elaborate interiororganization, have different organellesthat create separate compartments forcellular functionNUCLEUS?NOYESMEMBRANE BOUND ORGANELLESNOYES (many)SIZE1-10 µm10-50 µmEVOLUTION3.5 billion years ago1.5 billion years agoCYTOPLASMYESYESCELL MEMBRANEYESYESCELL WALLSome doPlantsRIBOSOMESYESYESDNACircular Free FloatingChromosomes in nucleusSample Organism(s)BacteriaPlants, animals, fungi, and protists
PROKARYOTES vs. EUKARYOTES
STRUCTURE OF THE CELL Main components Cell membrane – continuous in the cell’s internal membrane Cytoplasm – living matter within the cell, has fluid jellylike substance calledhyaloplasm Nucleus – control unit of the cells, enclosed in a nuclear membrane
STRUCTURE OF THE CELL––––––Plasma gh EndoplasmicReticulum– Smooth EndoplasmicReticulum–––––Golgi Complex / ApparatusLysosomesCytoskeletonMicrotubulesCilia and Flagella
CELL: Main Components Plasma Membrane / Cell MembraneStructure: composed of double layerphospholipids in whichproteins are embeddedFunction: - gives form to the cell andcontrols the passage ofmaterials- acts as a selectively permeableboundary between the cell andits external environment- controls the passage ofmaterials in and out of the cell
CELL: Main Components NucleusStructure: separated by a porous nuclearmembrane within thecytoplasm, sphere shaped,contains the nucleolusFunction: - control center of the cells- storage center of cells’ DNA Nucleolus – aggregate of granules madeof ribonucleic acid (RNA)
CELL: Main Components CytoplasmStructure: gelatin-like fluid that lies insidethe cell membraneFunction: - contains salts, minerals andorganic molecules- surrounds the organelles
CELL: Genetic Composition ChromosomesStructure: threadlike strands,composed of nuclear DNAFunction: carries geneticinformation
CELL: Energy Processing MitochondriaStructure: double walledmembranous sacs withfolded inner partitionscalled cristaeFunction: releases energy fromfood molecules andtransform energy intousable ATP whichhappens during cellularrespiration
CELL: Cell Manufacturers Ribosomes Endoplasmic Reticulum Rough Endoplasmic Reticulum Smooth Endoplasmic Reticulum Golgi Apparatus / Complex
CELL: Cell Manufacturers RibosomesStructure: - granular particlescomposed of proteinand RNA molecules,- consists of twosubunits made ofprotein and RNAFunction: - synthesize proteinmolecules that may beused to build cellstructures or to functionas enzymes
CELL: Cell Manufacturers Endoplasmic Reticulum- a series of membranous channels thattraverse the cytoplasm of most eukaryoticcells- A continuous network extending from the cellmembrane to the nuclear membrane Rough Endoplasmic Reticulum (rER)Structure: - ribosomes are attachedat the ERFunction: - active protein synthesis Smooth Endoplasmic Reticulum (sER)Structure: - does not contain ribosomesFunction: - synthesis and transport oflipids or detoxification ofpoisons within the cells
CELL: Cell Manufacturers Golgi Apparatus / ComplexStructure: cluster of flattenedmembranous sacs thatare continuous withinthe channels of the sERFunction: - receiving processing packaging shipping- responsible for thestorage, modificationand packaging ofmaterials produced forsecretory export, its outerportion releases secretorymaterial within vesiclesthat migrate to the surfaceof the cell
CELL: Breakdown of Materials LysosomesStructure: - single walled membranoussacs- contain hydrolyticenzymeswithin the singlemembranesFunction: - responsible in digestion ofnutrients, bacteria anddamaged organelles- used to destroy certaincells (apoptosis)
CELL: Support and Movement CytoskeletonStructure: a network of thin, fibrouselements made up ofmicrotubules (hollowtubes) and microfilaments(threads made out of actin) Function: - acts as a support systemfor organelles- maintains cell shape
CELL: Support and Movement Microtubules Structure: - thin hollow tubesFunction: - supports the cytoplasmand transport materialswithin cytoplasm
CELL: Support and Movement Cilia and FlagellaStructure: - minute cytoplasmicprojections that extendsfrom the cell surface When they are present in large numbers on a cellthey are called cilia When they are less numerous and longer theyare called flagella Both organelles are composed of nine pairs ofmicrotubules arranged around a central pair.Function: - cell motility
All living things are composed of one or more cells. Cells are organisms’ basic units of structure and function Cells come only from preexisting cells “All organisms are made up of one or more cells, within
How are organisms organized? Many-celled organisms are organized in cells, tissues, organs, and organ systems. Cells: Animals and plants are many-celled organisms. Animals are made up of many kinds of cells. You are made of blood cells, bone cells, skin cells, and many others. A plant also has different cells in its roots, stems, and leaves.
3H-Thymidine, and the new cells express neuronal or glial markers. 10 Subventricular Zone (SVZ) x Six types of cells in the SVZ: ependymal cells neural stem cells (B cells) transit amplifying cells (C cells) neuroblasts & glioblasts (A cells) .
Cells are the fundamental unit of life (the basic unit of organization). All organisms are composed of cells. All cells come from preexisting cells. Common Characteristics Of Cells Cells must obtain and process energy Cells convert genetic in
A cell is the smallest unit of life. 2. Cells make up all living things. 3. New cells only arise from preexisting, living cells. Categories of cells Eukaryotic cells Categories of cells Prokaryotic cells. 2 Cell structure 1. Plasma membrane 2. Nucleus 3. Cytoplasm Plasma membr
Animal and Plant Cells 2 Slide Eukaryotic Cells Animals and plants are eukaryotes. A eukaryote is an organism that is composed of one or more cells. Eukaryotic cells contain . Similarities between Animal Cells and Plant Cells Both animal and plant cells have an reticul
koh) said all cells come from cells that already exist. The observations made by these scientists, shown in the table below, became known as the cell theory. The cell theory states that all living things are made of one or more cells, cells are the smallest unit of life, and all new cells come from
coordinate the activities of all of the other white blood cells and are essential for fighting disease. There are two major types of T cells: Helper T cells (T H) and Killer T cells (T K). Helper T cells send signals that activate the rest of your immune system to fight a germ. Killer T cells patrol the body and eliminate infected cells.
The facts and extensive procedural history of Albert Woodfox’s case have been recounted time and again, but they bear repeatingsince they factored into theunconditional writ granted by the district court On April 17, 1972, . Correctional Officer Brent Millerof the Louisiana State Penitentiary in , Angola, Louisiana, was found murderedin the prison dormitory , havingbeen stabbed 32 times. The .
