Answer:
White blood cells (WBCs) are specialized to respond to antigen and produce antibodies as well as undergo phagocytosis in response to toxic stimuli.
 
WBCs are part of immune system and there are five different kinds with specialized features. 
 
In order to make a cell model, it is best to use a muscle cell and a nerve cell or neuron: there are pronounced structural differences and those are present throughout animal kingdom.
 
Lower animals ( such as insects, worms etc. ) have different immune system, however, they do have typical neuron and a muscle cell/skin cell (fibroblast). Such cell models are likely to be easy, distinct and bring you good grades without going through much complication and confusions of various organ systems and animal mod
Explanation:
 
        
             
        
        
        
Answer:
These reactions are collectively called the urea cycle or the Krebs-Henseleit cycle. Ammonia is a toxic product of nitrogen metabolism which should be removed from our body. The urea cycle or ornithine cycle converts excess ammonia into urea in the mitochondria of liver cells.
 
        
             
        
        
        
2. third quarter 7. first quarter 1. waxing gibbous 8. waning gibbous 5. waning cresent 3. waxing cresent
        
             
        
        
        
Answer:
 All the matter to ever exist was created in the big bang. The amount of space between clumps of matter is increasing, which is allowing the expansion of the universe. There are plenty of conditions for the every matters being created.