Question

14. Lab Exercise 5-1 is an interesting way to run these test tube experiments without oxygen - seal the tube with a layer of clear mineral oil on top (see the figure in the manual). Based on this figure and the Table of Results for this experiment, if the sealed tube is all green or slightly blue but the unsealed tube has any amount of yellow, what type of energy metabolism does that organism have? a. Oxidative only b. Oxidative and/or fermentation c. Fermentation only d. Nonsaccharolytic - organism does not metabolize sugar 15. One of the tests you will be using to identify your unknowns is the Phenol Red Broth test (with lactose as the sugar) (Lab Exercise 5-2). The Phenol Red Broth test is what type of test? a. Aerobic respiration b. Anaerobic respiration c. Fermentation. d. All of the above 16. Fermentation occurs when (see Chapter 5 of the textbook): a) Oxygen is absent. b) The absence of an electron acceptor causes the Krebs Cycle to shut down. c) The absence of an electron acceptor causes the ETC to shut down. d) All of the above 17. Based on your previous experience in lab, what will you use to inoculate the Phenol Red Broths? a Inoculating loop b. Inoculating needle c. Sterile serological pipette d. Sterile cotton swab 18. If fermentation results in the production of acid, what color will the phenol red indicator turn? a. Yellow b. Red c. Pink d. Colorless 19. If deamination of amino acids results in the production of NH3, what color will the phenol red indicator turn? 2. Yellow b. Orange c. Pink to Red d. Colorless 20. The Phenol Red test utilizes a small tube inverted in the test tube called a (see the Materials section of the directions): a. Fermentation tube b. Durham tube c. Phenol red tube d. Carbohydrate utilization tube

Answer 1

Ans 14) b oxidation and or fermentation

Ans15) c.. Fermentation.

Ans 16 d.. All of above.

Ans 17)a. Inoculating loop.

Ans 18) a. Yellow.

Ans 19)c. Pink to red.

Ans20) b. Durham tube.