Microbiology Chapter 4 Questions
The smallest eukaryotic cell is the motile alga micromonas. What is the minimum number of organelles this alga must have?
Nucleus, mitochondrion, chloroplasts, and flagellum
The antibiotic amphothericin B disrupts plasma membranes by combining with sterols; it will affect all of the following cells except a) animal cells b) gram-negative bacterial cells c) fungal cells d) mycoplasma cells e) plant cells
B. gram-negative bacterial cells
Which of the following pairs is mismatched? a) glycocalyx - adherence b) pili - reproduction c) cell wall - toxin d) cell wall - protection e) plasma membrane - transport
B. pili - reproduction
Compare and contrast simple diffusion and facilitated diffusion.
Both allow materials to cross the plasma membrane from a high concentration to a low concentration without expending energy. Facilitated diffusion requires carrier proteins.
Compare and contract active transport and group translocation.
Both move materials across the plasma membrane with an expenditure of energy. In group translocation, the substrate is changed after it crosses the membrane.
Compare and contrast active transport and facilitated diffusion.
Both require enzymes to move materials across the plasma membrane. In active transport, energy is expended.
Which of the following statements best describes what happens to a cell exposed to polymyxins that destroy phospholipids? a) in an isotonic solution, nothing will happen b) ina hypotonic solution, the cell will lyse c) water will move into the cell d) intracellular contents will leak from the cell e) any of the above might happen
D. intracellular contents will leak from the cell
Use the following choices to answer the next questions: a) no change will result; the solution is isotonic b) water will move into the cell c) water will move out of the cell d) the cell will undergo osmotic lysis e) sucrose will move into the cell from an area of higher concentration to one of lower concentration Which statement best describes what happens when a gram-positive bacterium is placed in distilled water and penicillin? Which statement best describes what happens when a gram-negative bacterium is placed in distilled water and penicillin? Which statement best describes what happens when a gram-positive bacterium is placed in an aqueous solution of lysozyme and 10% sucrose?
D. the cell will undergo osmotic lysis B. water will move into the cell A. no change will result; the solution is isotonic
Match the following: a) Pericentriolar material 1. Digestive enzyme storage b) Chloroplasts 2. Oxidation of fatty acids c) Golgi complex 3. Microtubule formation d) Lysosomes 4. Photosynthesis e) Mitochondria 5. Protein synthesis f) Peroxisomes 6. Respiration g) Rough ER 7. Secretion
A. 3 B. 4 C. 7 D. 1 E. 6 F. 2 G. 5
Match the following: _____a) Cell wall 1. Attachment to surfaces _____b) Endospore 2. Cell wall formation _____c) Fimbriae 3. Motility ___d) Flagella 4. Protection from osmotic lysis _____e) Glycocalyx(2) 5. Protection from phagocytes _____f) Pili(2) 6. Resting _____g) Plasma membrane(2) 7. Protein synthesis _____h) Ribosomes 8. Selective permeability 9. Transfer of genetic material
A. 4 B. 6 C. 1 D. 3 E. 1, 5 F. 3, 9 G. 2, 8 H. 7
Endospores formation is called (a) _______. It is initiated by (b) _______. Formation of a new cell from an endospore is called (c) ________. This process is triggered by (d) _______.
A. Sporogenesis B. Certain adverse environmental conditions C. Germination D. Favorable growth conditions
You have isolated a motile, gram-positive cell with no visible nucleus. You can assume this cell has a) ribosomes b) mitochondria c) an endoplasmic reticulum d) a golgi complex e) all of the above
A. ribosomes
What group of microbes is characterized by cells that form filaments, reproduce by spores, and have peptidoglycan in their cell walls?
Actinomycete
Why is an endospore called a resting structure? Of what advantage is an endospore to a bacterial cell?
An endospore is called a resting structure because it provides a method for one cell to 'rest' or survive, as opposed to grow and reproduce. The protective endospore wall allows a bacterium to withstand adverse conditions in the environment.
Starch is readily metabolized by many cells, but a starch molecule is too large to cross the plasma membrane. How does a cell obtain the glucose molecules from a starch polymer? How does the cell transport these glucose molecules across the plasma membrane?
An extracellular enzyme hydrolyzes starch into disaccharides and monosaccharides. A carrier enzyme hydrolyzes maltose and moves one glucose into the cell. Glucose can be transported by groups translocation as glucose-6-phosphate.
Which of the following pairs is mismatched? a) metachromatic granules - stored phosphates b) polysaccharide granules - stored starch c) lipid inclusions - poly-b-hydroxybutyric acid d) sulfur granules - energy reserve e) ribosomes - protein storage
E. ribosomes - protein storage
Which of the following is not a distinguishing characteristic of prokaryotic cells? a) they usually have a single, circular chromosome b) they lack membrane-enclosed organelles c) they have cell walls containing peptidoglycan d) their DNA is not associated with histones e) they lack a plasma membrane
E. they lack a plasma membrane
Which of the following is false about fimbriae? a) they are composed of protein b) they may be used for attachment c) they are found on gram-negative cells d) they are composed of pilin e) they may be used for motility
E. they may be used for motility
How can prokaryotic cells be smaller than eukaryotic cells and still carry on all the functions of life?
Prokaryotic cells just need respiration replication to sustain unicellular body.
Two types of prokaryotic cells have been distinguishes: bacteria and archaea. How do these cells differ from each other? How are they similar?
Similar: prokaryotic and single celled Different: bacteria cell walls have peptidoglycan, Archaea is composed of branched carbon chains, Bacteria is composed of straight carbon chains.