BIOL 1201 Lecture : Notes3 9 3
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I need help on this microbiology question:
Contrary to our favorite science fiction books and movies, the chances of us finding another planet with a civilization comparable to, or even more advanced than our own, seems highly unlikely. But, through your work as a microbiologist at NASA, you have been able to help change our views as to what forms of life we should be looking for on planets in our solar system and around neighboring stars. Instead of radio signals or errant transmissions, we have begun looking for planets that have environments similar to those capable of sustaining life as we know it here on Earth. To determine what we could find out there, you have begun studying different unique and atypical environments found here on Earth. Although the harsh conditions of hot springs or undersea sulfur vents seem incompatible with most forms of life, organisms known collectively as "extremophiles" have still managed to survive and adapt to these extreme conditions. You believe extremophiles may help you gain insight into the potential metabolic requirements, processes, and challenges of extraterrestrial life. Thus far in your search, you have identified some prokaryotic cells that have evolved to survive in the extreme conditions of sulfur vents on the sea floor. These vents are found at great depths, where the crushing pressure and lack of light and oxygen are prohibitive to many forms of life. Bacteria that are not considered extremophiles reside in most ecological niches on this planet. There are some common criteria for the environment that would sustain these bacteria. Availability of water, pH that lies between 5 and 9, temperatures that will remain steady and below boiling; these are some of the characteristics that bacteria will require in their environment if they are to succeed. But in the environment of the ocean floor vents, not only is the pH of the water very low, but also the water temperature is unusually high due to the geologic activity that fuels the vents. Organisms that are adapted to such harsh conditions have necessarily evolved enzymes able to function beyond average optima, as well as a chemosynthetic metabolism capable of using vent organic and inorganic compounds as energy sources.
Part A - Comparable Earth Environments to Be Found on Another Planet
You identify the prokaryotic cells you've found as a species of bacteria. These bacteria appear to be living off of nutrients and sulfur compounds released from the vents on the sea floor. Over time, the bacteria must have evolved extreme metabolic and enzymatic capabilities to allow them to tolerate and even benefit from the extreme depths, the lack of oxygen, the low pH of the surrounding waters, high temperatures due to volcanic releases, and the unique nutrient source of the vents.
Choose the characteristics and their impact on enzyme activity that are not correct from the following statements. (more than one may be chosen)
Archaea are able to tolerate highly acidic pH environments and have proteins that will not denature in the low-pH environments that the bacteria are found in. |
Archaea are able to colonize water that is at or above the boiling temperature due to high levels of disulfide bridges that maintain the three-dimensional structure of the enzyme. |
Archaea are only able to survive exceedingly well at high temperatures due to the amount of activation energy required by their enzymes. |
Archaea are able to grow in extremely shady or low-light conditions that allow for optimal enzyme activity. |
No handwriting please and only answer if you are gonna complete all of them from 30-40. Thanks in advance and hope you are having a great day today.
Select the correct answer:
30. How would amino acids from the bloodstream move across a cell membrane?
a. | diffusion | |
b. | osmosis | |
c. | facilitated diffusion | |
d. | active transport | |
e. | endocytosis |
31. Which of the following is not a greenhouse gas?
a. | water vapor | |
b. | carbon dioxide | |
c. | gaseous nitrogen | |
d. | methane | |
e. | nitrous oxide |
32. The greenhouse effect is most similar to
a. | heating up the air inside a car by parking it in the sun | |
b. | warming the air for a hot-air balloon with a propone burner | |
c. | burning kerosene in a heater to warm up the air inside a cold house | |
d. | growing plants in your office to reduce indoor air pollution | |
e. | cooking food with a charcoal grill |
33. Temperature is a measure of
a. | the potential energy in a substance | |
b. | how fast the molecules in a substance are moving | |
c. | the energy lost from a substance to its surroundings | |
d. | how much heat is being absorbed by a substance |
34. Fossil fuels include all the following EXCEPT
a. | oil | |
b. | coal | |
c. | hydrogen gas | |
d. | natural gas | |
e. | gasoline |
35. On Earth,________is/are the largest reservoir of carbon dioxide and heat.
36. Chemical work within cells is powered by
a. | NAD+ | |
b. | NADPH | |
c. | ADP | |
d. | ATP |
38. Which of the following processes creates the most ATP per glucose molecule metabolized?
a. | glycolysis | |
b. | fermentation | |
c. | photorespiration | |
d. | aerobic cellular respiration | |
e. | the light reactions of photosynthesis |
39. In cellular respiration,_______is produced during_______.
a. | oxygen; the citric acid cycle | |
b. | carbon dioxide; the citric acid cycle | |
c. | oxygen; the light reactions | |
d. | carbon dioxide; the light reactions |
40. Metabolic pathways that require oxygen are referred to as
a. | aerobic | |
b. | anaerobic | |
c. | photosynthetic | |
d. | fermentative |