During cellular respiration, carbon dioxide is produced. carbon dioxide is taken in by plants during photosynthesis to make food hence removing carbon dioxide from the atmosphere. These two processes make up the carbon cycle which maintains the concentration of carbon dioxide in the atmosphere.
        
             
        
        
        
14. Dermis
15. Chemical
17. Virus
18. Antibodies
19. Gas exchange
20. Ligament
Hope this helps!
        
             
        
        
        
B. thick atmosphere
You can also use quizlet to look up answers also, I'm in college and they have never failed me. 
        
             
        
        
        
Drug that demages capsule is used to treat viral infection because Curing a viral infection  antibiotics are useless against viral infections. This is because viruses are so simple that they use their host cells to perform their activities for them. So antiviral drugs work differently to antibiotics, by interfering with the viral enzymes instead.  
Antiviral drugs are currently only effective against a few viral diseases, such as influenza, herpes, hepatitis B and C and HIV – but research is ongoing. A naturally occurring protein, called interferon (which the body produces to help fight viral infections), can now be produced in the laboratory and is used to treat hepatitis C infections.
 
        
             
        
        
        
Answer:
safari could help, learnt this a few years ago, totally forgot!! 
Explanation:
:).