Correct answer - Tetrahedral, planar or flat.
Why? - When carbon forms single bonds with other atoms, the shape is tetrahedral. When two carbon atoms form a double bond, the shape is planar, or flat. Single bonds, like those found in ethane, are able to rotate.
Respiratory system helps in breathing and it leads to exhalation of the gas carbon dioxide which is not required by the body. The integumentary system is the first line of defense and protects the body from invadig microbes, dust, and other harmful substances. The digestive system protects the body by enabling digestio of food and providing energy to sustain, further the toxic waste materials are also released during the process.
Answer:
It needs the spines for protection
Explanation:
The cactus would develop the spines as a form of protection to protect itself from being consumed and to survive longer.
The system of classification relates to the diversity of species because the system of classification is how we organize the diversity of species. With out it we would have a hard time trying to determine which animals belong with which group. There would be no order, just chaos of trying to determine animal likeness of one another.
To cut this answer short, it helps them organize organisms.