Answer:
Scientific theory definition, a coherent group of propositions formulated to explain a group of facts or phenomena in the natural world and repeatedly confirmed through experiment or observation: the scientific theory of evolution.
Explanation:
While photosynthesis requires carbon dioxide and releases oxygen, cellular respirationrequires oxygen and releases carbon dioxide. It is the released oxygen that is used by us and most other organisms for cellular respiration. We breathe in that oxygen, which is carried through our blood to all our cells.
Answer:
To survive in drought conditions, plants need to decrease transpiration to limit their water loss. Some plants that live in dry conditions have evolved to have smaller leaves and therefore fewer stomata. Extreme examples are plants with leaves that resemble spiky thorns or spines.