Chapter 4- Micro

Which of the following is a difference between gram-positive and gram-negative cells? Selected Answer: A. Only gram-negative cells have a lipopolysaccharide (LPS) layer. B. Gram-positive cells contain less peptidoglycan than do gram-negative cells. C. Only gram-positive cells have peptidoglycan that is made of a carbohydrate backbone. D. Gram-negative cell walls contain teichoic acids

A. Only gram-negative cells have a lipopolysaccharide (LPS) layer. Answers:

Which drawing in Figure 4.1 is a tetrad? A. a B. b C. c D. d E. e

B.

Which of the following statements is TRUE? A. Endospores are for reproduction. B. Endospores allow a cell to survive environmental changes. C. Endospores are easily stained in a Gram stain. D. A cell produces one endospore and keeps growing. E. A cell can produce many endospores.

B.

Bacteria are a commonly used organism for studies of genetic material in the research laboratory. The nucleic acids must first be isolated from the cells for these studies. Which of the following would most likely be used to lyse the bacterial cells for nucleic acid isolation? A. lysozyme B. polymixins C. alcohol D. water E. mycolic acid

A. lysozyme

Antibiotics that target cell wall synthesis ultimately cause bacterial cell death as a result of A. osmotic lysis. B. inhibition of molecular transport. C. decreased synthesis of peptidoglycan. D. plasmolysis. E. cell shrinkage.

A. osmotic lysis

What statement most accurately describes the structure of the plasma membrane? Selected Answer: A. The plasma membrane is a phospholipid bilayer with the hydrophilic phosphate groups oriented toward the inside and outside of the cell. B. Peripheral proteins span the membrane. C. The lipid portion of the bilayer is hydrophilic. D. The plasma membrane is a phospholipid bilayer with the hydrophilic phosphate groups oriented toward one another.

A. The plasma membrane is a phospholipid bilayer with the hydrophilic phosphate groups oriented toward the inside and outside of the cell. Answers:

During endospore formation, ________. Selected Answer: A. a thick spore coat forms around the forespore before the endospore is released into the environment B. the only DNA that is copied contains the genes necessary for germination C. the cell is experiencing a great deal of metabolic activity D. the population of bacterial cells doubles

A. a thick spore coat forms around the forespore before the endospore is released into the environment Answers: A. a thick

Which of the following statements is true regarding the principles of osmosis? Selected Answer: A. The relative concentrations of solutes inside and outside the cell have no influence on the direction of osmosis. B. If a cell is a hypertonic solution, water leaves the cell in an attempt to balance to concentration of solutes and reach equilibrium. C. If a cell is in an isotonic solution, no water moves across the membrane because equilibrium has been reached. D. If a cell is a hypotonic solution, water leaves the cell in an attempt to balance to concentration of solutes and reach equilibrium.

B. If a cell is a hypertonic solution, water leaves the cell in an attempt to balance to concentration of solutes and reach equilibrium. Answers:

Which structure acts like an "invisibility cloak" and protects bacteria from being phagocytized? A. slime layer B. fimbriae C. capsule D. cell membrane E. cell wall

C.

You have isolated a motile, gram-positive cell with no visible nucleus. You can safely assume that the cell A. has 9 pairs + 2 flagella. B. has a mitochondrion. C. has a cell wall. D. lives in an extreme environment. E. has cilia.

C. has a cell wall.

Which one of the following pairs is mismatched? A. metachromatic granules - phosphate storage B. lipid inclusions - energy reserve C. ribosomes - protein storage D. sulfur granules - energy reserve E. gas vacuoles - flotation

C. ribosomes - protein storage

Which one of the following pairs is mismatched? A. metachromatic granules - phosphate storage B. lipid inclusions - energy reserve Correct C. ribosomes - protein storage D. sulfur granules - energy reserve E. gas vacuoles - flotation

C. ribosomes - protein storage

In a hypertonic solution, a bacterial cell will typically A. lyse. B. burst. C. stay the same. D. plasmolyze. E. osmolyze

D.

Which of the following is NOT a typical characteristic of most bacterial plasma membranes? A. site of energy production B. composed of a phospholipid bilayer C. contains proteins D. contains cholesterol E. is selectively permeable

D.

Which of the following pairs is mismatched? A. endoplasmic reticulum - internal transport B. Golgi complex - secretion C. mitochondria - ATP production D. centrosome - food storage E. lysosome - digestive enzymes

D. centrosome - food storage

Which of the following is NOT a functionally analogous pair? A. nucleus -nucleiod region B. mitochondria - prokaryotic plasma membrane C. chloroplasts - thylakoids D. cilia - pili E. 9+2 flagella - bacterial flagella

D. cilia - pili

Functions of the glycocalyx include all of the following EXCEPT A. biofilm formation. B. increased virulence. C. source of nutrition. D. protection against dehydration. E. binary fission.

E.

Functions of the glycocalyx include all of the following EXCEPT A. biofilm formation. B. increased virulence. C. source of nutrition. D. protection against dehydration. E. binary fission.

E.

Which of the following statements is correct about diffusion? A. It requires an expenditure of energy by the cell. B. It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration. C. It is an active process in which molecules move from a region of lower concentration to one of higher concentration. D. It may require a transport protein. Correct E. It involves movement of molecules down a concentration gradient and may require a transport protein.

E.

Which of the following statements is correct about diffusion? A. It requires an expenditure of energy by the cell. B. It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration. C. It is an active process in which molecules move from a region of lower concentration to one of higher concentration. D. It may require a transport protein. E. It involves movement of molecules down a concentration gradient and may require a transport protein.

E.