Answer: 2
Explanation: There's X (female) and Y (male).
Gametes that are motile are often called sperm.
6. a - transgenic organism is one whose genetic material has been altered by genetic engineering (i.e. man!)
9. a - biomedical research
10. b
13. b
16. d
18. b
Answer:
Movement in narrow zones along plate boundaries causes most earthquakes. Most seismic activity occurs at three types of plate boundaries—divergent, convergent, and transform. As the plates move past each other, they sometimes get caught and pressure builds up.
To explain the nature of things
