The patient wears reading glasses. Explain degenerative changes that occur in the eye as we age and how this may have resulted people need to wear...

The patient wears reading glasses. Explain degenerative changes that occur in the eye as we age and how this may have resulted people need to wear glasses.

 Differentiate between pulmonary ventilation, internal respiration and cellular respiration.  

 What is required to ensure a cell remains healthy?