1. when examining cells in the lab, you notice that a particular tissue sample has 45% of the cells in the mitotic phase, how do you explain this observation?

This observation shows that the tissue is growing or renewing itself.

Most tissues of the body grow by increasing their cell number which is achieved via mitosis (cell division). This kind of growth is highly regulated in order to maintain a balance between different tissues. On the other hand, cell division is involved in tissue renewal where many types of cells undergo continuous replacement. The example is skin. Skin cells are constantly being replaced by division of immature stem cells (the mature differentiated cells do not divide).

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.