Simplify the following text for a Grade 13 native English-speaking person.
Original: Many of the complex traits related to sexual reproduction , photosynthesis , and other defining characteristics of plants evolved first in charophyceans ; analysis of cpDNA ( chloroplast DNA ) , for instance , reveals that many characteristics of plant chloroplasts evolved first in the charophycean genera Staurastrum and Zygnema .
Simplified: Many of the complex traits related to sexual reproduction , photosynthesis , and other plant characters , evolved first in charophyceans . Analysis of cpDNA ( chloroplast DNA ) shows that characteristics of plant chloroplasts evolved first in the charophycean genera Staurastrum and Zygnema .