1. Many of species of milkweed are among the most dangerous of poisonous plants , while others have little , if any, toxicity.

2. Humans do not constitute the only species endowed with intelligence: the higher animals also have considerably problem-solving abilities.

3. The globe artichoke was known as a delicacy at least 2,500 years ago , and records of its cultivation date from fifteenth century.

4. While the process of photosynthesis in green plants, light energy is captured and used to convert water, carbon dioxide, and minerals into oxygen and organic compounds.

5. The mechanism of human thought and recall, a subject only partly understood by scientists , is extraordinary complicated.

6. At first the poems of E.E. Cummings gained notoriety to their idiosyncratic punctuation and typography, but they have gradually been recognized for their lyric power as well.

7. The carbon-are lamp, a very bright electric lamp used for spotlights, consists of two carbon electrodes with a high-current arc passing between it .

8. Cheese may be hard or soft, depending on the amount of water left into it and the character of the cuting.

9. The lemur is an unusual animal belonging to the same order than mon’s and apes

10. Political parties in the United States help to coordinate the campaigns of their members and organizes the statewide and nationa conventions that mark election years .

11. The sounds used in human languages to create meaning consist of small variation in air pressure can be sensed by the ear.

12. The piano is a stringed musical instrument in which the strings are strike by felt-covered hammers controlled by a board.

13. Photograph was revolutionized in 1851 by the introduction of the collodion process for making glass negatives.

14. Ice crystals in a glacier tends to melt and recrystallize within a brief moment of travel on a downhill glide.

15. Among the symptoms of measles, which takes about twelve days to incubate, are a high fever, swelling of glands in the neck, a cough, and sensitive to light.

16. Originally canoes were made by the hollowing out of logs and used were for combat as well as transport.

17. Native to South America and cultivated there for thousands of years, the peanut is said to have introduced to North America by early explorers.

18. There are as many as 200 million insects for every human beings , and in fact their total number exceeds that of all other animals taken together.

19. Onyx is a mineral that can be recognized its regular and straight parallel bands of white, black, or brown.

20. The law of biogenesis is the principle what all living organisms are derived from a parent or parents .

21. Guitarlike instruments have exist since ancient times, but the first written mention of the guitar itself is from the fourteenth century.

22. The eighteenth century witnessed the emergence of North American ports, particular Boston, New York, and Philadelphia, as major commercial centers within the British empire.

23. In the early 1900’s, Roy Harris created and promoted a distinctly American style of classical music and greatly influenced a number of composer in the United States.

24. In the orbit of a planet around the Sun, the point closest to the Sun is called it the perihelion.

25. The pear tree has simple , oval leaves that are smoother and shinier than them of the apple.