Spirochetes and spirilla are both spiral-shaped bacteria. However, they differ in that spirochetes have __________ and spirilla do not.endoflagellaYou are observing a Gram stain of rod-shaped microorganisms that are linked in a chain and stain purple. How would you describe these bacteria using the correct terminology for the cell shape and arrangement?Gram-positive streptobacilliWith a light microscope, which of the following would allow discrimination between eukaryotes and prokaryotes?Observation of nucleiWhy is penicillin selectively toxic to bacterial cells but harmless to human cells?Penicillin specifically weakens peptidoglycan, which is found only in bacterial cells.Chemotaxis refers to the ability of microorganisms to __________.move toward or away from chemical stimuliMany pathogenic (disease-producing) bacteria produce a(n) __________ that protects them from phagocytosis by host cells.capsuleIn a prokaryotic cell, all of the following are functions of either fimbriae or pili EXCEPT __________.protection from phagocytosisWhich of the following pairs is matched correctly?
Mycoplasma spp.—bacteria that spontaneously, or in response to penicillin or lysozyme, partially lose their cell walls and swell into irregularly shaped bacteria that divide and metabolize and may regain their cell wall
protoplast—a genus of bacteria that typically do not have cell walls
spheroplast—gram-negative bacteria that are exposed to lysozyme but retain some of the outer membrane
L form—a wall-less bacterium created by the action of lysozyme; the plasma membrane remains intact, and the cell carries on metabolismspheroplast—gram-negative bacteria that are exposed to lysozyme but retain some of the outer membraneWhich of the following bacterial structures is necessary for chemotaxis?FlagellaThe term describing bacteria with flagella that are arranged as a tuft coming from one pole is __________.lophotrichousThe term describing bacteria with flagella distributed over the entire surface of the cell is __________.peritrichousThe __________ is a fluid structure that allows membrane proteins to move freely.cell membraneWhich of the following membrane transport mechanisms takes place in eukaryotic cells but NOT in prokaryotic cells?EndocytosisWhich of the following statements is true?
One bacterial cell produces many endospores.
Endospores are extremely durable structures that can survive high temperatures.
Endospores allow a cell to attach to solid surfaces and to surfaces within the host.
Endospores are reproductive structures.Endospores are extremely durable structures that can survive high temperatures.The endoplasmic reticulum that has ribosomes attached to its outer surface is referred to as __________.rough ERA __________ solution is a medium in which the overall concentration of solutes equals that found inside the cell. Water enters and leaves the cell at the same rate.isotonicA population of bacterial cells has been placed in a very nutrient-poor environment with extremely low concentrations of sugars and amino acids. Which kind of membrane transport becomes crucial in this environment?Active transportWhich of the following processes requires cellular energy in the form of ATP?Active transportA eukaryotic cell can ingest a prokaryotic cell by __________.phagocytosisWhich of the following statements about ribosomes is FALSE?
Antibiotics that interfere with protein synthesis harm both prokaryotic and eukaryotic ribosomes.
Cells with a high rate of protein synthesis have large numbers of ribosomes.
Antibiotics that interfere with protein synthesis harm prokaryotic ribosomes, but not eukaryotic ribosomes.
Eukaryotic ribosomes are larger (80S) than prokaryotic ribosomes (70S).Antibiotics that interfere with protein synthesis harm both prokaryotic and eukaryotic ribosomes.The plasma membrane is considered a barrier to the environment because __________.it controls the passage of molecules into the cellWhich of the following statements does NOT provide evidence for the endosymbiotic theory?
Mitochondria and chloroplasts contain circular DNA, similar to the DNA in prokaryotes.
Prokaryotes contain peptidoglycan in their cell walls.
The ribosomes contained within mitochondria and chloroplasts are very similar to prokaryotic ribosomes.
The same antibiotics that inhibit protein synthesis in prokaryotes also inhibit protein synthesis within mitochondria and chloroplasts.Prokaryotes contain peptidoglycan in their cell walls.Which of the following pairs is MISMATCHED?
Endoplasmic reticulum; internal transport
Mitochondria; ATP production
Lysosome; digestive enzymes
Golgi complex; secretion
Ribosomes; storageRibosomes; storageYou have isolated a cell with a peptidoglycan cell wall. What other structure can you safely assume the cell has?A plasma membraneWhich of the following processes uses membrane proteins that act as channels or carriers allowing ions or large molecules to move across the plasma membrane without using energy?
Simple diffusion
Active transport
Osmosis
Facilitated diffusionFacilitated diffusionThe nucleus of a eukaryotic cell differs from the nucleoid of a prokaryotic cell in all of the following ways EXCEPT which one?
The eukaryotic nucleus contains nucleoli. There are no nucleoli in the prokaryotic nucleoid.
The prokaryotic nucleoid usually contains a single circular chromosome, whereas the eukaryotic nucleus contains multiple linear chromosomes.
The eukaryotic nucleus is surrounded by a nuclear envelope. There is no envelope surrounding the prokaryotic nucleoid.
The prokaryotic nucleoid contains DNA combined with histones. Histones are lacking in the eukaryotic nucleus.The prokaryotic nucleoid contains DNA combined with histones. Histones are lacking in the eukaryotic nucleus.
