Presentation on theme: "Microscopes, Cell and it’s Organelles Nestor T. Hilvano, M.D., M.P.H. (Images Copyright Discover Biology, 5 th ed., Singh-Cundy and Cain, Textbook, 2012.)"— Presentation transcript:
Microscopes, Cell and it’s Organelles Nestor T. Hilvano, M.D., M.P.H. (Images Copyright Discover Biology, 5 th ed., Singh-Cundy and Cain, Textbook, 2012.)
Learning Objectives 1.Differentiate light microscope and electron microscope. 2.What are the functions of cells? 3.Differentiate prokaryotes and eukaryotes. 4.Describe organelles of cells as to structure and functions. 5.Describe the nucleus and its parts. 6.Describe the energy processing organelles of cells in animal and plant as to structure and functions. 7.Discuss the 3 types of cytoskeletons.
Word stems cyto – cell; endo – inner ex – out; extra – outside chloro – green; lyso – loosen trans – across; micro – small nucleo – nucleus ; -oid – like vacu – empty; flagell –whip hyper – exceeding; hypo – lower tonus – tension
Microscope and Cell Theory Cell Theory: 1.All living things are composed of cells 2.All cells come from pre-existing cells. 3.Cell is the smallest unit that exhibits all the characteristics of life. Van Leeuwenhoek- discovered microscope; studied cork “little rooms or cells”
Types of Microscope Light microscope - refraction of light; glass lenses, can magnify objects about 1,000 times, resolution of 0.2 m Electron microscope – focus beam of electrons; magnify 10,000 times to 100,000M times, resolution of 0.2 nm; dead materials a.scanning EM = study details of cell surfaces (3D) b.transmission EM = study details of internal cell structure
Functions of cells Produce macromolecules Excrete waste products Gather raw materials Grow and reproduce
2 Main Types of Cells a)Prokaryotes = include Domain bacteria, Domain archaea - hallmark feature: smaller size, no nucleus, have DNA (nucleoid), lack (other) membrane bound organelles; found in extreme environment (temp., salty, pH, chemicals), cell wall, capsule, pili, & flagella. b) Eukaryotes = include plants, animals, fungi, protists - hallmark features: larger size, have nucleus (with DNA), membrane bound organelles; a) animal cells have mitochondria, lysosome, cell membrane; b) plant cells = have central vacuole, chloroplast, cell wall * Similarities= cell (plasma) membrane, DNA, ribosomes, and cytoplasm can be found in both main types, prokaryotes and eukaryotes * Differences= size, membrane bound organelles, and cell wall/capsule in prokaryotes, cell wall in plants
Organelles __contains most of DNA in eukaryotes, genetic center. __synthesis of protein __ synthesis of lipids, detoxify poisons, store calcium, metabolize CHO __ has bound ribosomes __ sorts and package materials into transport vesicles __ digest macromolecules (phagocytosis) __ oxidative organelles __ sites of cellular respiration in animal cells (Krebs’s cycle), make ATP (powerhouse of cell); energy processing in animals __ has a pair of centrioles, important in cell division. __ sites of photosynthesis in plants and algae; energy processing in plants __ holds organic compound and water in plants; store food a. mitochondria b. rough ER c. lysosome d. centrosome e. vacuole f. ribosomes g. smooth ER h. chloroplast i. peroxisome j. nucleus k. golgi apparatus
Cytoskeletons Functions: Supporting structures, forms shape, movements a.Microfilaments – solid rods composed of globular protein (actin monomers); shape/movement of cell b.Microtubules – hollow tubes composed of globular protein (tubular subunits); cell division- internal movement of organelles c.Intermediate filaments – ropelike strands of fibrous protein; anchor organelles/shape Cilia- hair-like, movement (ciliary beat) in 1 direction Flagella- whip-like, can undergo rotation (like propellers)
Cell Wall Extracellular structure in plant cells Prokaryotes, fungi, and some protists also have cell walls Protects the plant cell, maintains its shape, and prevents excessive uptake of water Plant cell walls are made of cellulose fibers embedded in other polysaccharides and protein Plasmodesmata are channels between plant cells
Homework 1.Define – cell, organelles, cytoskeletons, nucleoid, cell wall, cilia, flagella, nuclear pores, cell wall, cell membrane, and plasmodesmata. 2.Compare and contrast light microscope and electron microscope. 3.What is magnification and resolution (resolving power) of microscopes? 4.Compare similarities and differences of prokaryotic cells and eukaryotic cells and give an examples. 5.State the function/s of the following structures of cell: lysosome, nucleus, rough endoplasmic reticulum, golgi apparatus, microtubule, mitochondria, smooth ER, free ribosomes, peroxisomes, mitochondria, chloroplast, central vacuole. 6.State primary functions of cell. 7.Describe the 3 types of cytoskeletons.