Answer:
a. parasitism:
The parasite benefits by harming the host e.g hookworms and humans
b. commensalism
In this association, one species benefits while the other is unaffected (its not harm and dies not benefit) e.g. epiphytic orchids and trees
c. mutualism
Here, both species benefit as seen in rumen bacteria and cows
Explanation:
Parasitism = +/- relationship
The predator benefits by harming the host. E.g. hookworms and humans. The hookworm (parasite) eat man blood while man (host) loses blood to it.
Commensalism = +/0 relationship
One specie(s) benefits while the other specie(s) neither benefits nor is harmed. E.g. epiphytic orchids live on tree branches or tree trunks as it's habitat or shelter while the trees neither benefits nor is harmed
Mutualism = +/+ relationship
Both organisms benefit in this relationship. E.g. rumen microbes aids grass digestion in cows, while the microbes benefit as it obtain steady food or nutrient from the cow
 
        
             
        
        
        
Density-dependent regulation can be affected by factors that affect birth and death rates such as competition and predation.
 
        
                    
             
        
        
        
The Krebs cycle is the second step in the breakdown of glucose takes
place when oxygen is present.<span> This step completes the
breakdown of glucose to carbon dioxide and water, and produces much more ATP
than glycolysis.</span>
 
        
             
        
        
        
You didn't attach the problem. Without it, I can't help you. Sorry.
 
        
                    
             
        
        
        
Answer:
by altering the ligand-binding site of the receptor - by increased translation of the receptor - by decreased phosphorylation of the receptor - through a conformational change of the receptor...
Explanation: