What does stirring do in an experiment

How does the author's purpose in this passage differ from an author writing about her personal struggle living with asthma?

What is the following best defines climate?

Which organelles are labeled d, and what is one feature that distinguishes them from the other labeled organelles chloroplasts the only organelles that produce sugars from sunlight mosomes, only found in animal and bacterial cells centricles only found in animal cells mitochondra, the only energo-generating structures found in cells