Pupil! The pupil is the black hole that you see when you look into someone’s eye, the light passes through that hole first.
        
             
        
        
        
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The correct answer would be "NADH delivers its electrons to complex I and FADH₂ deliver its electrons to complex II" in cellular respiration.
There are mainly four complexes associated with electron transport chain of cellular respiration.
Complex I or NADH: ubiquinone oxidoreductase is the complex at which NADH is oxidized to form NAD⁺. The free electrons are transported with the help of ubiquinone.
Complex II or succinate dehydrogenase is the complex associated with oxidation of FADH₂ to FAD⁺. It also transports the free electrons with the help of the ubiquinone pool.
Complex III or cytochrome bc1 complex transport free electrons from ubiquinone to the cytochrome C which is a water-soluble electron carrier.
Complex IV or cytochrome c oxidase transport the free electrons to oxygen to form water.
 
        
             
        
        
        
Answer:
the shape of white blood cells
 
        
                    
             
        
        
        
Answer:
The oxygen enters the bloodstream from the alveoli, tiny sacs in the lungs where gas exchange takes place (Figure below). The transfer of oxygen into the blood is through simple diffusion. ... While oxygen moves from the capillaries and into body cells, carbon dioxide moves from the cells into the capillaries.
Explanation: