Catabolism is a the breakdown of larger molecules into small

Catabolism is: a. the breakdown of larger molecules into smaller molecules and energy intermediates. b. the assembly of smaller molecules into macromolecules and biomass. c. the of sum of all metabolism and anabolism in the cell. d. a process only done chemoorganoheterotrophs. Which of the following statements is true for both PTS transport and ABC-type transport? a. Transport chemically modifies the substrate during uptake. b. Transport does not change the substrate gradient. c. Transport requires specific proteins for each substrate. d. None of the above. You need to determine the number of cells in an environmental sample, but you do not know how to grow the cells in the lab. What method of determining cell number would you use? a. Direct counting b. Viable counting c. Dilution planting d. Spectrophotometry Which of the following environmental parameters are halophiles most resistant to? a. heat b. pressure c. desiccation d. detergents Which of these specifically describes an organism that uses lipids as its energy source? a. phototroph b. chemotroph c. prototroph d. heterotroph

Solution

6. A. Breakdown of large molecules into smaller molecules and energy intermediates.

7.

8. C. Dilution plating.

Dilution plating is a simple technique used to estimate the number of heterotrophic bacteria in an environmental sample.

9. Dessication.

To survive the high salinities, halophiles employ different strategies to prevent desiccation through osmotic movement of water out of their cytoplasm.

10. Chemotroph.

Chemotrophs are organisms that obtain energy by the oxidation of electron donors in their environments. Chemotrophs can be either autotrophic or heterotrophic.

Chemoautotrophs derive energy from chemical reactions, and synthesize all necessary organic compounds from carbon dioxide. Chemoautotrophs use inorganic energy sources, such as hydrogen sulfide, elemental sulfur, ferrous iron, and also molecular hydrogen, and ammonia.

Chemoheterotrophs can be chemolithoheterotrophs, utilizing inorganic energy sources such as sulfur or chemoorganoheterotrophs, utilizing organic energy sources such as carbohydrates, lipids, and proteins.