State two functions of centrioles in an animal cell.

Here are the answers to questions 1, 2, and 3:

1. State two functions of centrioles in an animal cell.

   • Centrioles are involved in the formation of spindle fibers during cell division (mitosis and meiosis).
   • They are also involved in the formation of cilia and flagella.

2. Name two classes of phylum Arthropoda that have a cephalothorax.

   • Arachnida (e.g., spiders, scorpions)
   • Crustacea (e.g., crabs, lobsters)

3. State Two types of air pollutants and their sources.

   • Carbon monoxide: Produced primarily from the incomplete combustion of fossil fuels in vehicles and industrial processes.
   • Sulfur dioxide: Released mainly from the burning of fossil fuels (especially coal) in power plants and industrial facilities.