A: The corneal reflex is an involuntary closing of the eyelids when the cornea is touched by a foreign object. The function of this reflex is to protect the eye from damage. Absence of a corneal reflex may indicate damage to the fifth and seventh cranial nerves, which mediate the reflex.
Cellular respiration is the process by which the chemical energy of food molecules is released and partially captured in the form of ATP. Carbohydrates, fats, and proteins can all be used as fuels in cellular respiration, but glucose is most commonly used as an example to examine the reactions and pathways involved.
Respiration occurs when glucose (sugar produced during photosynthesis) combines with oxygen to produce useable cellular energy. This energy is used to fuel growth and all of the normal cellular functions. Carbon dioxide and water are formed as by-products of respiration (Figure 4).hotosynthesis uses energy from light to convert water and carbon dioxide molecules into glucose (sugar molecule) and oxygen (Figure 2).