The answer is A The amino acid inactivates the repressor
B looks like the best to me
Answer:
14 CO₂ will be released in the second turn of the cycle
Explanation:
<u>Complete question goes like this</u>, "<em>The CO2 produced in one round of the citric acid cycle does not originate in the acetyl carbons that entered that round. If acetyl-CoA is labeled with 14C at the carbonyl carbon, how many rounds of the cycle are required before 14CO2 is released?</em>"
<u>The answer to this is</u>;
- The labeled Acetyl of Acetyl-CoA becomes the terminal carbon (C4) of succinyl-CoA (which becomes succinate that is a symmetrical four carbon diprotic dicarboxylic acid from alpha-ketoglutarate).
- Succinate converts into fumarate. Fumarate converts into malate, and malate converts into oxaloacetate. Because succinate is symmetrical, the oxaloacetate can have the label at C1 or C4.
- When these condense with acetyl-CoA to begin the second round of the cycle, both of these carbons are discharged as CO2 during the isocitrate dehydrogenase and alpha-ketoglutarate dehydrogenase reactions (formation of alpha-ketoglutarate and succinyl-CoA respectively).
Hence, 14 CO₂ will be released in the second turn of the cycle.
Answer:
<em>This is an example of natural selection (adaptation).</em>
Explanation:
Natural selection tends to favor those organisms which are better adapted to live in an environment.
As tortoises having flat shell and long neck were better adapted to live in barren area, hence through natural selection those organisms were favored in such an ecosystem.
As tortoises that lived on the vegetative lands were more adapted to live in such an ecosystem, hence through natural ecosystem these organisms were favored and increased in numbers.
