This is a large opening in the occipital bone of the cranium through which the medulla oblongata (an extension of the spinal cord) enters and exits the skull vault. in humans, it is farther underneath the head than in other great apes.

the unequal cytoplasmic division that  results  in  one egg  and three polar bodies ensures that a fertilized  egg has  ample nutrients  forits journey  to  the uterus.

photosynthesis makes the glucose that is used in cellular respiration to make atp. the glucose is then turned back into carbon dioxide, which is used in photosynthesis. while water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water.