Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Unit 5
MICRO EXAM 2
| Question | Answer |
|---|---|
| What enables the copied chromosomes to separate during binary fission? | The chromosomes are attached to different parts of cell membrane, which elongates and thus separates the chromosomes. |
| How long does it take for the daughter cells from one round of replication to replicate themselves? | No time is required -- they are ready to divide immediately after DNA replication and separation of the daughter cells is complete if conditions are right. |
| Put the following steps of bacterial replication in the correct order, starting from a parent cell. Cell elongation Septum formation Chromosome replication Separation of daughter cells | 3, 1, 2, 4 |
| What would happen if the septum did not form during binary fission? | The parent cell would now have two copies of the chromosome |
| Starting with three cells, how many cells would result from three rounds of replication? | Twenty-four |
| Microbial growth is generally described as an increase in cell number rather than the expansion in size of an individual microbial cell. | True |
| Fts proteins are essential for bacterial cell division because they __________. | are responsible for pulling apart the two copies of the chromosome are responsible for forming the divisome are responsible for peptidoglycan synthesis |
| The time interval required for the formation of two cells from one is called the | generation time |
| Which of the following is/are transferred to daughter cells during bacterial cell division? | chromosome, proteins, and all other cellular constituents |
| If a bacterial culture contains 1 cell at time zero, 4 cells after 1 hour, and 16 cells after 2 hours, then all EXCEPT which of the following are true | The growth rate is increasing with each generation |
| The lag phase does NOT occur if an exponentially growing culture is transferred into a nutrient rich medium with the same components and growth conditions as the previous medium. | True |
| Which of the following statements is FALSE? | In the lag phase, cell death exceeds cell division. |
| Cell density in a chemostat is controlled by | the concentration of the limiting nutrient. |
| A selective medium is used to suppress the growth of certain bacteria in order to facilitate the growth of other bacteria. | True |
| Microbial contamination is prevented by the | use of aseptic technique. |
| Selective medium differs from differential medium because | selective medium permits growth of a particular microbial type while differential medium is used to distinguish between types of organisms. |
| A medium containing known substances in precise amounts is known as a ________ media. | defined |
| Serial dilutions are generally made | to reach a suitable dilution while minimizing error. based on powers of 10, although other serial dilution factors are possible. when the appropriate viable count is unknown. |
| Direct microscopic counting of cells is an accurate method for estimating the number of viable cells in a sample. | false |
| Turbidity measurements are commonly utilized for monitoring | planktonic cultures. |
| Refrigeration controls microbial growth in food as a result of irreversible cell damage caused by low temperature. | False |
| Organisms able to live in environments with high sugar concentrations are | osmophiles |
| When water activity is low, an organism must | increase its internal solute concentration |
| Superoxide dismutase and catalase work together to convert superoxide into | water and oxygen. |
| Which of the following forms of oxygen is/are generally toxic to living organisms? | Superoxide, hydrogen peroxide, and hydroxyl radicals are all toxic. |
Created by:
user-1993459