The answer is D its tightly packed cells allow for proctection against harmful substances.
Chloroplasts
In plants and algae, which developed much later, photosynthesis occurs in a specialized intracellular organelle—the chloroplast. Chloroplasts perform photosynthesis during the daylight hours. The immediate products of photosynthesis, NADPH and ATP, are used by the photosynthetic cells to produce many organic molecules. I have taken the test before
Global warming
The increase of greenhouse gases result into global warming :)
RNA polymerase binds to the lac promoter and begins transcribing
the stretch of DNA to messenger RNA.
Therefore, in other words, the stretch of DNA is expressed. The DNA sequence of
the lac promoter 'signals' where the RNA
polymerase will bind and where transcription
will begin. Promoters are found upstream of a gene to be transcribed.