The eons that make up 90% of Earth's history are the Precambrian eons, which consists of Hadean, Archean, and Proterozoic eons.
The best answer is C - to break down food into nutrients.
The digestive system breaks down food into its simplest form that cell are able to utilize for energy. Food is broken down into its monomer units. Proteins are broken down into amino acids, lipids are broken down into fatty acids and glycerol and carbohydrates are broken down into glucose.
Glucose is then absorbed into the blood and transported to every cell in the body. The cells take in glucose and use it as fuel and raw material in the process of cellular respiration. From one molecule of glucose, 36 to 38 molecules of ATP ( the form of energy used by cells) are produced.
<span>D. Temperature and pH can affect how enzymes work.</span> The action of enzymes can be affected by many factors including temperature, pH and ionic strength. Optimum pH differs per enzyme. Enzymes can be destroyed by heat more than the allowed optimum temperature.
