Quiz 1 (Module 1-4) Flashcards
- Microbial Classification - Microscopy - Prokaryotic Cell Structure - Eukaryotic Cell Structure
FITB Name for rod shaped bacteria: _____
Bacillus
FITB Name for round shaped bacteria: _____
Cocci
FITB The most widely-accepted current model for the plasma membrane is called: _____
Fluid mosaic
FITB Sterol-like molecules called _____ are thought to be important for the structural integrity of many bacteria because of their suspected role in stabilizing the plasma membrane.
Hopanoids
FITB Gram _____ bacteria have a structurally and chemically more complex cell wall than the Gram _____.
Negative, Positive
FITB In eukaryotes, ribosomes synthesizing proteins that are to be excreted are typically located: _____
On the endoplasmic reticulum (RER)
SA What two key features distinguish a prokaryotic cell from a eukaryotic cell?
- membrane bound nucleus
- presence of specialized organelles
SA What is a plasmid?
A small circular loop of double stranded DNA molecules that encode genetic information that is additional, but not essential for life, that may confer an advantage.
SA What are the two functions of the eukaryotic cytoskeleton?
- determine cell shape
- aid in motility
- aid in division
- intracellular transport
SA What is the function of lysosomes?
Intracellular digestion: membrane bound organelles that contain enzymes that help digest products that enter the lysosome and then excrete them to be used as nutrients.
SA What is the difference between antiseptic and disinfectant?
Antiseptics: destroy or inhibit microorganisms on living tissues.
Disinfectants: kill microorganisms on inanimate objects.
T/F Electron microscopes have higher resolution than light microscopes because the wavelength of the electron beams is much longer than that of light.
False, electron beams have a shorter wavelength
T/F Scanning electron microscopes use electrons reflected or scattered from the surface of a conductive sample to generate an image that provides a 3D image of surface structure.
True, SEM are used to form a 3D image
T/F The plasma membrane is a major site of ATP synthesis in bacteria growing under aerobic conditions.
True,
T/F Bacterial plasmids can replicate independently of the host chromosome.
True, plasmids are completely independent of chromosomal DNA
T/F Chemotaxis is only observed in prokaryotes.
False,
T/F DNA is replicated prior to the start of mitosis.
True, DNA must be replicated before the cell is able to divide into two daughter cells
MC The major site of cell membrane synthesis in eukaryotes is:
A) Nucleus
B) Plasma Membrane
C) Lysosome
D) Endoplasmic Reticulum
D) Endoplasmic Reticulum
MC The process by which a cell imports large particles by enclosing them in vesicles pinched off from the plasma membrane is called:
A) Exocytosis
B) Phagocytosis
C) Pinocytosis
D) Nutrient Cytosis
B) Phagocytosis
SA What is microbiology
The study of microorganisms too small to be seen clearly by the unaided eye.
SA Name 3 industry specific or commercial applications that involve using micro-organisms.
- Food production (yogurt, bread)
- Fermentation (wine, beer, fish sauce)
- Medication (insulin, penicillin)
- Biofuel
- Vaccine production
- Wastewater treatment
SA What is resolution meant in microscopy.
The ability of the microscope to separate or distinguish small objects that are close together.
SA List 5 types of light microscopes and 2 types of electron microscopes.
- Brightfield
- Darkfield
- Phase contrast
- Fluorescent
- Confocal
- Scanning electron microscope
- Transmission electron microscope
FITB The three domains of life are _____, _____, and _____.
eukarya, bacteria, archaea
FITB A compound microscope has a two lens system, the _____ is the lens closer to the specimen and the the _____ lens is located in the eye piece.
objective, ocular
FITB _____ and _____ fixation are two general methods or fixing samples in preparation for staining.
Heat, Chemical
FITB During gram staining what is:
The primary stain: _____
The mordant: _____
The counterstain: _____
Crystal violet, Gram’s iodine, Safranin
T/F Viruses must invade a host cell in order to replicate.
True
T/F As the magnification of a series of objective lenses increases, the working distance increases.
False, the working distance decreases as the magnification increases
T/F In gram staining, after decolorization, gram negative organisms will appear clear/colourless.
True
T/F Phase contrast microscopy is useful for examining living cells and can allow visualization of some internal structures in eukaryotic cells.
True
T/F A light microscope with a 10 X lens, with a numerical aperture of 0.25 is capable of distinguishing two objects that are 1 micron apart when using light with a wavelength of 450nm.
True
SA Name the steps of gram staining
Crystal violet -> Gram iodine -> Decolourizer -> Safranin
SA Describe the structure and function of the cytoskeleton. (3 components)
Microtubules, microfilaments, intermediate filaments.
The cytoskeleton is responsible for maintaining cell shape and provide a basis for movement and division.
SA Describe the secretory pathway, identifying the key organelles
involved. To what destinations does this pathway deliver proteins
and other materials?
Ribosomes synthesize protein at the ER -> cis face then trans face of golgi apparatus -> plasma membrane or lysosomes
SA What is endocytosis? Describe 4 different endocytic pathways
observed in eukaryotes.
Endocytosis is used to bring materials into the cell.
Phagtocytosis - cell surface protrusions surround particles creating vesicles.
Clathrin - coated pits bind to macromolecules
Caveolae - cavelolar vesicles
Macropinocytosis -
SA How do free ribosomes and those bound to the ER differ in
function?
ER bound ribosomes synthesize secretory proteins that are often used for the plasma membrane. Free ribosome synthesize non secretory proteins.
SA What is the difference between mitosis and meiosis?
Mitosis produces two daughter cells with identical DNA and is asexual.
Meiosis is the sexual phase of the life cycle where DNA becomes mixed and unique.
SA Brightfield microscopes are used for
Fixed dyed specimens
SA Darkfield microscopes are used for
Viewing internal structures of living unstained eukaryotes
SA Phase contrast microscopes are used for
Contrast intracellular structures with different refractive index. Living cells
SA Fluorescent microscopes are used for
Tagging parts of a cell’s internal structure with different dyes
SA Confocal microscopes are used for
Similar to fluorescent but works on living things in 3D
SA TEM microscopes are used for
Uses transmitted electrons to view vruses and super tiny micro-organisms
SA SEM microscopes are used for
Uses reflected electrons to view in 3D
SA Probe microscopes are used for
A small probe moves up and down “feeling” out the surface of the specimen. This then creates an image of the surface. Used for things at the nanoscale level.
