micro lecture 4

Card Set Information

Author:
shaiangelz
ID:
88689
Filename:
micro lecture 4
Updated:
2011-06-06 14:49:34
Tags:
micro lecture ch4
Folders:

Description:
micro lecture 4
Show Answers:

Home > Flashcards > Print Preview

The flashcards below were created by user shaiangelz on FreezingBlue Flashcards. What would you like to do?


  1. comepare and contrast the overall cell structure of prokaryotes and eukaryotes
    • prokaryotes:
    • single celled
    • small (.5-5μm)
    • peptidoglycan cell wall
    • lack distinct membrane bound nucleus
    • DNA is circular
    • ribosomes are free in the cytoplasm

    • eukaryotes:
    • single celled & complex organisms
    • larger (up to 40μm)
  2. id the 3 basic shapes of bacteria
    • coccus (spherical)
    • bacillus (rod-shaped)
    • spiral (twisted)
  3. describe the function of the glycocalyx, flagella, cilia, fimbriae, and pili
    glycocalx-capsule (may protect pathogens from phagocytosis; enable adherence to surfaces, prevent desiccation and may provide nutrients), slime layer, or extracellular polysccharide; is a gelatinous polysaccharide and/or polypeptide covering

    flagella-relatively long filamentous appendages consisting of a filament, hook, and basal body; prokaryotic flagella rotate to push the cell; motile bacteria exhibit taxis; positive taxis is movement toward an attractant, and neg taxis is movement away from a repellent; flagellar (H) protein functions as an organism

    cilia- A short, microscopic, hairlike vibrating structure. Cilia occur in large numbers on the surface of certain cells, either causing currents in the surrounding fluid, or, in some protozoans and other small organisms, providing propulsion

    • fimbriae and pili are short, thin appendages;
    • fimbriae help cells adhere to surfaces
    • pili join cells for the transfer of DNA from one cell to another
  4. compare and contrast the cell walls of gram-postive bacteria, gram-negative bacteria, acid-fast bacteria and Archaea
    gram pos- cell walls consists of many layers of peptidoglycan and also contain teichoic acids

    gram neg- have a lipopolysaccharide-lipoprotein-phospholipid outer membrane surrounding a thin peptidoglycan layer

    acid-fast- cell walls have a layer of mycolic acid outside a thin peptidoglycan layer

    Archaea-have pseudomurein; they lack peptidoglycan
  5. describe the structure, chemistry and functions of the prokaryotic plasma membranes
    • layer of phospholipids and proteins that separates cytoplasm from external environment
    • regulates flow of material in and out of cell
    • membrane proteins are used in respiration, electron transport, and nucleic acid synthesis

    • made of:
    • phospholipid bilayer
    • peripheral proteins
    • integral proteins
    • transmembrane proteins

    • phospholipids rotate and move laterally
    • selective permeability allows passage of some molecules
    • proteins move to allow passage of molecules
  6. define simple diffusion, facilitated diffusion, osmosis, and active transport
    simple diffusion- molecules and ions move until equilibrium is reached

    facilitated diffusion-substances are transported by transporter proteins across membranes from areas of high to low concentration

    osmosis-movement of water from areas of high to low concentration across a selectively premeable membrane until equilibrium is reached

    active transport-materials move from areas of low to high concentration by transporter proteins, and the cell must expend enerty
  7. id the functions of the ribosomes and inclusions
    ribosomes-the cytoplasm of a prokaryote contains numerous 70S ribosomes; ribosomes consist of rRNA and protein; protein synthesis occurs at ribosomes; it can be inhibited by certain antibiotics

    inclusions-reserve deposits found in prokaryotic and eukaryotic cells; among the inclusions found in bacteria are metachromatic granules (inorganic phospate), polysaccharide granules (usually glycogen or starch), lipid inclusions, sulfur granules, carboxysomes (ribulose 1, 5-diphosphate carboxylase), magnetosomes (Fe3O4) and gas vaculoes
  8. describe the functions of endospores
    • resting structures formed by some bacteria; they allow survival during adverse environmental conditions
    • the process of endospore formation is called sporulation; the return of an endospore to its vegetative state is called germination

    • Certain bacteria can form endospores in dry environments in a process called sporulation. They are called endospores because the spores form within the cell.
    • Endospores offer great advantages to bacterial cells because they are extremely resistant to a number of harsh environments, including: heat, desiccation,
    • radiation, chemicals, acids, and drying. The discovery of bacterial endospores was important to microbiology because it provided knowledge on proper methods for sterilization of culture media, foods, and other perishable items
  9. compare and contrast prokaryotic and eukaryotic cell walls and glycocalyxes
    • Prokaryotic cell wall:
    • 1. The cell wall surrounds the plasma membrane and protects the cell from changes in water pressure.
    • 2. The bacterial cell wall consists of peptidoglycan, a polymer consisting of NAG and NAM and short chains of amino acids.
    • 3. Penicillin interferes with peptidoglycan synthesis.
    • 4. Gram-positive cell walls consist of many layers of peptidoglycan and also contain teichoic acids.
    • 5. Gram-negative bacteria have a lipopolysaccharide-lipoprotein-phospholipid outer membrane surrounding a thin peptidoglycan layer.
    • 6.The outer membrane protects the cell from phagocytosis and from penicillin, lysozyme, and other chemicals.
    • 7. Porins are proteins that permit small molecules to pass through the outer membrane; specific channel proteins allow other molecules to move through the outer membrane

    • Glycocalyx of Prokayotic
    • The glycocalyx (capsule, slime layer, or extracellular polysaccharide) is a gelatinous polysaccharide and/or polypeptide covering.
    • Capsules may protect pathogens from phagocytosis.
    • Capsules enable adherence to surfaces, prevent desiccation, and may provide nutrients



    • The Cell Wall and Glycocalyx of Eukaryotic cells
    • 1. The cell walls of many algae and some fungi
    • contain cellulose.
    • 2. The main material of fungal cell walls is
    • chitin.
    • 3. Yeast cell walls consist of glucan and
    • mannan.
    • 4. Animal cells are surrounded by a glycocalyx,
    • which strengthens the cell and provides a means of attachment to other cells.
  10. compare and contrast prokaryotic and eukaryotic cytoplasms
    • Cytoplasms of Prokaryotic cells:
    • 1. The plasma membrane encloses the cytoplasm and is a lipid bilayer with peripheral and integral proteins (the fluid mosaic model).
    • 2. The plasma membrane is selectively permeable.
    • 3. Plasma membranes carry enzymes for metabolic
    • reactions, such as nutrient breakdown, energy production, and photosynthesis.
    • 4. Mesosomes, irregular infoldings of the plasma
    • membrane, are artifacts, not true cell structures.
    • 5. Plasma membranes can be destroyed by alcohols
    • and polymyxins.
    • 6. Cytoplasm is the fluid component inside the plasma membrane.
    • 7. The cytoplasm is mostly water, with inorganic and organic molecules, DNA, ribosomes, and inclusions

    • Cytoplasms of Eukaryotic cells:
    • 1. Like the prokaryotic plasma membrane, the eukaryotic plasma membrane is a phospholipid bilayer containing proteins.
    • 2. Eukaryotic plasma membranes contain carbohydrates attached to the proteins and sterols not found in prokaryotic cells (except Mycoplasma bacteria).
    • 3. Eukaryotic cells can move materials across
    • the plasma membrane by the passive processes used by prokaryotes and by active transport and endocytosis (phagocytosis and pinocytosis).
    • 4. The cytoplasm of eukaryotic cells includes
    • everything inside the plasma membrane and external to the nucleus.
    • 5. The chemical characteristics of the cytoplasm
    • of eukaryotic cells resemble those of the cytoplasm of prokaryotic cells.
    • 6. Eukaryotic cytoplasm has a cytoskeleton and exhibits cytoplasmic streaming
  11. define organelle
    specialized membrane-enclosed structures in the cytoplasm of eukarytoic cells

    • 1. Organelles are specialized membrane-enclosed structures in the cytoplasm of eukaryotic cells.
    • 2. The nucleus, which contains DNA in the form
    • of chromosomes, is the most characteristic eukaryotic organelle.
    • 3. The nuclear envelope is connected to a system
    • of membranes in the cytoplasm called the endoplasmic reticulum (ER).
    • 4. The ER provides a surface for chemical
    • reactions, serves as a transporting network, and stores synthesized molecules.
    • Protein synthesis and transport occur on rough ER; lipid synthesis occurs on smooth ER.
    • 5. The Golgi complex consists of flattened sacs
    • called cisterns. It functions in membrane formation and protein secretion.
    • 6. Lysosomes are formed from Golgi complexes.
    • They store digestive enzymes.
    • 7. Vacuoles are membrane-enclosed cavities
    • derived from the Golgi complex or endocytosis. They are usually found in plant cells that store various substances, help bring food into the cell, increase
    • cell size, and provide rigidity to leaves and stems.
    • 8. Mitochondria are the primary sites of ATP
    • production. They contain 70S ribosomes and DNA, and they multiply by binary fission.
    • 9. Chloroplasts contain chlorophyll and enzymes
    • for photosynthesis. Like mitochondria, they contain 70S ribosomes and DNA and multiply by binary fission.
    • 10. A variety of organic compounds are oxidized in
    • peroxisomes. Catalase in peroxisomes destroys H2O2.
  12. describe the functions of the nucleus, endoplasmic reticulum, ribosomes, Golgi complex, lysosomes, vacuoles, mitochondria, chloroplasts, peroxisomes and centrosomes
    • the nucleus, which contains DNA in the form of chromosomes, is the most characteristic of eukaryotic organelle
    • the nuclear envelope is connected to a system of membranes in the cytoplsm called the EndoplasmicReticulum
    • the ER provides a surface for chemical reactions, serves as a transporting network, and stores synthesized molecules. Protein
    • synthesis and transport occur on rough ER; lipid synthesis occurs on smooth ER
    • the golgi complex consists of flattened sacs called cisterns. It functions in membrane formation and protein secretion
    • lysosomes are formed from Golgi complexes. They store digestive enzymes
    • vaculoles are membrane-enclosed cavities derived from the Golgi complex or endocytosis. They are usually found in plant cells that store various substances, help bring food into the cell, increase cell size and provide rigidity to leaves and stems
    • Mitochondria are promary sites of ATP production. They contain 70S ribosomes and DNA, and they multiply by binary fission
    • Chloroplasts contain chlorophyll and enzymes for photosynthesis. Like mitochondria, they contain 70S ribosomes and DNA multiply by binary fission
    • peroxisomes
    • centrosomes
  13. discuss evidence that supports the endosymbiotic theory of eukaryotic evolution
    according to the endosymbiotic theory, eukaryotic cells evolved from symbiotic prokaryotes living inside other prokaryotic cells
  14. organelles
    specialized membrane-enclosed structures in the cytoplasm of eukarytoic cells
  15. prokaryotes
    • prokaryotes:
    • single celled very simple
    • small (.5-5μm)
    • peptidoglycan cell wall lack distinct membrane bound nucleus (no nucleus)
    • DNA is circularribosomes are free in the cytoplasm

    true bacteria (many of which are common causes of disease) and ancient bacteria (does not cause disease)

    made of external structures, cell wall, plasma membrane, cytoplasm, DNA, ribosomes

    • external structures include:
    • glycocalyx, flagella, fimbriae and pili

  16. eukaryotes
    • eukaryotes:
    • single celled & complex organisms
    • larger (up to 40μm)
    • has a true nucleus contained in a membrane bound structure
    • many membrane bound organelles
    • ribosomes attached to rough ER
    • only plant and fungal cells have cell wall

    • fall into 4 kingdoms:
    • protista -ex. algae, amoeba, slime molds
    • fungi -ex. mushrooms and yeast
    • plantae -ex. maple tree and green algae
    • animlia -ex. you

    • external structures:
    • flagella (longer) and cilia (shorter) used for movement

  17. binary fission
    • asexual reproduction
    • most common in prokaryotes
  18. coccus (cocci)
    • circular
  19. diplococcus
    • coccus divided and still connected
  20. streptococcus
    • chain of divided and still connected cocci
  21. staphylococcus
    • divided any ol' way and still connected...clusters
  22. cytokinesis
    The cytoplasmic division of a cell at the end of mitosis or meiosis, bringing about the separation into two daughter cells
  23. bacillus (bacilli)
    • rod-shaped
  24. diplobacilli
    • divided and still connected by twos
  25. streptobacilli
    • chain
  26. vibrios
    comma shaped bacteria..almost spirals
  27. spirilla
    spiral shaped
  28. spirochetes
    • A flexible spirally twisted bacterium (Treponema and other genera, order
    • Spirochaetales), esp. one that causes syphilis.
  29. glycococalyx
    • used for attachment and protection
    • important in disease
    • glycocalx-capsule (may protect pathogens from
    • phagocytosis; enable adherence to surfaces, prevent desiccation and may provide nutrients), slime layer, or extracellular polysccharide; is a gelatinous polysaccharide and/or polypeptide covering
  30. capsule
    • neatly organized
    • help adhere to solid surfaces and nutrients in the environment
    • major factor in the initiation of some bacterial diseases
    • may protect pathogens from phagocytosis;
    • prevent desiccation and may provide nutrients
  31. slime layer
    • unorganized and loose
    • cause bacteria to adhere to solid surfaces
    • help prevent the cell from drying out
  32. flagella
    • flagella-relatively long filamentous appendages consisting of a filament, hook, and basal
    • body; prokaryotic flagella rotate to push the cell; motile bacteria exhibit taxis;
    • positive taxis is movement toward an attractant, and
    • neg taxis is movement away from a repellent;
    • flagellar (H) protein functions as an organismcilia
  33. fimbriae
    • fimbriae and pili are short, thin appendages;
    • fimbriae help cells adhere to surfaces
    • spikes on bacteria
  34. pili
    fimbriae and pili are short, thin appendages;

    pili join cells for the transfer of DNA from one cell to another

    DNA transfer (sexual reproduction)
  35. cell wall
    • rigid cell wall gives the cell shape and surrounds the plasma membrane
    • prevents cell rupture (lysis)

    made of peptidoglycan in true bacteria

    determines if gram pos or neg
  36. peptidoglycan
    • polymer of disaccharide N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM)
    • linked by polypeptides
  37. NAG
    • N-acetylglucosamine (NAG)
    • one of the two sugars that make up peptidoglycan
    • "post of chain linked fence"
  38. NAM
    • N-acetylmuramic acid (NAM)
    • one of the two sugars that make up peptidoglycan
    • "post of chain linked fence"
  39. lipopolysaccharide
    A complex molecule containing both lipid and polysaccharide parts.
  40. phospholipid bilayer
    • type of plasma membrane
    • decides who gets in and out of the cell
    • type of fat with a phosphate group at the top
    • separates the cytoplasm from the outer environment

    • rotate and moves laterally
    • selective permeability allows passage of some molecules
  41. diffusion
    movement across membranes
  42. facilitated diffusion
    • facilitated diffusion-substances are transported by transporter proteins across membranes from areas of high to low concentration
    • sometimes you cant fit thru the door so you need help; these are the big doors
  43. osmosis
    • osmosis-movement of water from areas of high to low concentration across a selectively premeable membrane until equilibrium is reached
    • a type of simple diffusion
  44. osmotic pressure
    the pressure needed to stop the movement of water across the membrane
  45. isotonic solution
    • no net movement of water
    • makes happy cell
    • equal concentration inside and outside cell
  46. hypertonic solution
    • water moves out of cell
    • causing its cytoplasm to shrink (plasmolysis)
  47. hypotonic solution
    • water moves into cell
    • if the cell wall is strong it contains the swelling
    • if cell wall is weak or damaged, the cell bursts (osmotic lysis)
  48. active transport
    • active transport-materials move from areas of low to high concentration by transporter proteins, and the cell must expend energy (ATP)
    • against the gradient
  49. cytoplasm
    • a gel-like matrix of water, enzymes, nutrients, wastes and gases
    • in bacteria, where DNA is housed
    • the location of growth, storage of food and protein synthesis
  50. bacterial chromosome
    • The nucleoid (meaning nucleus-like) is an irregularly-shaped region within the cell of prokaryotes which has nuclear material without a nuclear membrane and
    • where the genetic material is localized
  51. plasmid
    • smaller circles of DNA
    • located in cytoplasm
    • can be shared when they have "sex" which is one of the advantages of having these for bacteria
  52. ribosome
    • where proteins are made
    • free and loose thruout the cytoplasm
    • 70S type (small) (smaller than eukaryotic)
    • translate the genetic code into protein
  53. inclusions
    reserved deposits for bacteria like a closet
  54. endospores
    • protective cells that are resistant to drying out (desiccation), heat and chemicals
    • resting cells
    • bacillus and clostridium species
    • sporulation: endospore formation
    • germination: return to vegetative (growing) state
  55. cilia
    • made of microtubules
    • tubulin (protein) - nine pairs + two arrangements
    • used for movement (motility)
  56. nucleus
    • the nucleus, which contains DNA in the form of chromosomes, is the most characteristic of eukaryotic organellethe
    • nuclear envelope is connected to a system of membranes in the cytoplsm called the EndoplasmicReticulum
    • double membrane-bound control center of cell
    • separates the genetic material from the rest of the cell
  57. endoplasmic reticulum
    • the ER provides a surface for chemical reactions, serves as a transporting network, and stores synthesized molecules.
    • Protein synthesis and transport occur on rough ER;
    • lipid synthesis occurs on smooth ER
  58. rough ER
    • Protein synthesis and transport occur on rough ER;
    • rough appearance bc it has ribosomes
    • helps make proteins, that's why it has ribosomes
  59. smooth ER
    • lipid synthesis occurs on smooth ER
    • no ribosomes
    • makes fats or lipids
  60. Golgi complex
    • the golgi complex consists of flattened sacs called cisterns.
    • It functions in membrane formation and protein secretion
    • modifies proteins and lipids and prepares for them export
  61. lysosome
    • lysosomes are formed from Golgi complexes.
    • They store digestive enzymes
    • digest cellular wastes
  62. mitochondria
    • Mitochondria are promary sites of ATP production.
    • They contain 70S ribosomes and DNA, and they multiply by binary fission
  63. chloroplasts
    • Chloroplasts contain chlorophyll and enzymes for photosynthesis.
    • Like mitochondria, they contain 70S ribosomes and DNA multiply by binary fission
  64. endosymbiotic theory
    • endo = within
    • symbiosis = to share
    • where eukaryotes came from

    according to the endosymbiotic theory, eukaryotic cells evolved from symbiotic prokaryotes living inside other prokaryotic cells

    • prokaryotic cells are similar to mitochondria and chloroplasts
    • they share:
    • 70S ribosomes
    • circular DNA
    • both reproduce independently
    • mechanism of protein synthesis

What would you like to do?

Home > Flashcards > Print Preview