Overtake (v.) means to catch up with something and then pass it. This can be in terms of movement/physical speed, or in terms of getting higher numbers:
With a final burst of speed, Gary overtook Paul and won the race.
The number of women in college has now overtaken the number of men.
Sales of the new product will likely overtake sales of the old product by the end of the year. (in these last two examples, we can also use "surpass")
To take over (v.) means to take control - one country can take over another country with military force; when a big company buys a smaller company, it takes over the management of the smaller company. The verb take over is two words, and the noun, referring to the action of taking control, is takeover.
Traditional Chinese medicine believes that bamboo shoots can cause uterine contractions. It is used as a medicinal supplement during the last month of pregnancy when the delivery date is still pending. According to the research papersubmitted by Gruber and O Brien at the University of Vienna, bamboo is one of the many plants which have been listed among uterotonic plants.