Answer:
Complex organic food molecules such as sugars, fats, and proteins are rich sources of energy for cells because much of the energy used to form these molecules is literally stored within the chemical bonds that hold them together.
Explanation:
 
        
             
        
        
        
Some dinosaur only ate plants and no meat. As plants became extinct the dinosaur who ate plants couldn’t get the food they need so they starved.
        
             
        
        
        
Answer/Explanation:
b) kidney and bladder
Kidneys are the main organ in the excretory system and the bladder stores the urine in the body. These are two of the organs that make up the excretory system.  
 
        
             
        
        
        
Answer:
Sexual reproduction results in genetic variation and asexual reproduction does not.
Explanation:
The key difference between sexual and asexual reproduction is that sexual reproduction occurs between two parents while asexual reproduction occurs via a single parent. Asexual reproduction requires only a single divisible cell to produce a new organism, whereas sexual reproduction requires two gametes, their formation and fusion.
 
        
             
        
        
        
Sea-floor spreading ovcurs at divergent boundaries which statement best identifies the geologic process taking place at the point where sea floor spreading occurs