Oxygen is a vital element within cellular respiration. An intrinsic part of the cellular respiration cycle is the transfer or electrons through the electron transport chain, and at the end of it exists the mitochondria, in which electrons are donated to the Oxygen and combine with hydrogen ions to form water.
        
             
        
        
        
Answer:
J. W. Tutt suggested that peppered moths were an example of natural selection. 
Explanation: Before industrial revolution, the population of white peppered moth is high as compared to dark peppered moth because white peppered moth can't be seen at night by the birds. After industrial revolution, sooth is spread on the surface of the trees which make easy for the bird to see white peppered moth and feeds on them. Population of white peppered moth decreases while the population of dark peppered moth increased because they cannot be seen in the dark due to black color of sooth. 
 
        
             
        
        
        
Explanation:
The function of the cell membrane is to protect the organelles that break down proteins and nutrients. 
It is semi-permeable which means it takes in select nutrients and excretes cell waste into the bloodstream. 
 
        
             
        
        
        
Answer:
Carbon dioxide and oxygen can't pass through the cuticle, but move in and out of leaves through openings called stomata 
Explanation: