B. Using fewer fossil fuels, such as gasoline for a car, reduces the emission of harmful pollutants into the air
I can answer the third one:
Photosynthesis takes place in two stages<span>: light-dependent reactions and the Calvin cycle (light-independent reactions).</span>
An example of a population in which evolution could take place in a relatively short period of time could be pathogenic bacteria exposed to antibiotics.
Answer: Option A
<u>Explanation:</u>
Evolution if takes place within a short period of time say the next generation that is called as micro evolution. This is caused when a specific organism exposed in a different environment at once modifies its genes to suit the new environment. This phenomenon can be very well seen in the pathogenic bacteria which are exposed to antibiotics.
When an antibiotic is prescribed to bacteria initially it nullifies its effect by destroying it. When continuously exposed to a certain antibiotic some bacteria dies but there are few which becomes resistant to it and survives. This on the other hand multiplies producing a generation that can’t be touched by the antibiotic.
The double membrane. It's theorized that chloroplasts used to be their own single-celled organism in the environment (and therefore with its own membrane). Then, the theory states, a larger cell took in the chloroplast by endocytosis, which involves surrounding the chloroplast in the large cell's own membrane. The chloroplast would then have two membranes surrounding it. This is similar to the thinking for mitochondria becoming an organelle as well. Hope this helps! :)