The process of respiration is essential in the oxygen/carbon dioxide cycle. Respiration removes OXYGEN from the atmosphere and produces and releases CARBON DIOXIDE to the atmosphere. answer is letter D.
Respiration driven by a mechanical series called inhalation and exhalation. We inhale or breathe in oxygen and exhale or breathe out carbon dioxide. 
        
                    
             
        
        
        
Answer:
B I think so 
Explanation:
If I'm right mark me as brainliest and follow e
 
        
                    
             
        
        
        
The cell theory was constructed by s<span>chleiden and schwann.</span>
        
                    
             
        
        
        
Answer:
The correct answer is "I, II, and III".
Explanation:
The missing options of this question are:
I only
II only
III only
I, II, and III
The correct answer is "I, II, and III".
Antibiotics are of different spectrums of activity depending on the number of pathogens they can kill. They are different reasons for this differences in antibiotic specificity:
I. Antibiotics interrupt processes found in some but not all pathogen cells. For instance, some antibiotics are directed to cell walls that not all bacteria posses.
II. Some pathogens have no metabolic processes to interrupt. The antibiotics that are directed to metabolic reactions of bacteria are not effective in treating viruses because they do not perform this metabolic reactions.
III. Some pathogens have developed genetic resistance to specific antibiotics. Bacteria have a remarkable genetic plasticity having plasmids that can be easily transmitted among them, which give them antibiotic resistance.
 
        
             
        
        
        
The provided question is incomplete, the correct and complete question is as follows:
Choose the answer that best completes the sentence below.
Scientists group materials together ____________ it is easier to compare and study them that way.
A however
B but
C although
D because 
Answer:
The correct answer is - option D because.
Explanation:
Researcher and scientists tries to group material together on their similarities and difference to one another which makes it easier to study and compare various type of materials.
It is the one of major reasons to differentiate materials between groups like liquids state, gases state,  plasma state and solid state materials. One can easily see the difference and comparison is very clear on this type of grouping of materials.
Thus, the correct answer is - option D.