Photosynthesis Explained

1. In order to explain how photosynthesis and respiration are linked you must first have a good definition of photosynthesis is. Photosynthesis is defined as how plant cells take in and process the sun's energy, in order to make energy for all other living things. Aerobic respiration is a part of the cellular respiration process that includes the presence of Oxygen. The first step of aerobic respiration is a process called Glycolysis, which is where the sugars are broken down during photosynthesis. So if oxygen is present when the glycolysis process is complete a process known as the Kerbs cycle releases the energy stored in pyruvates.

One way to explain how photosynthesis and respiration are linked is during the process; plants absorb carbon dioxide from the air and release oxygen. Animals take in the oxygen when they inhale and release carbon dioxide when they exhale. The two processes are linked in that both processes are a means of transforming an energy state into a more usable form of energy for the cell. The photosynthesis process in plants uses sun's energy, carbon dioxide, and water to create sugar and oxygen. When animals take in either the oxygen or the plants cellular respiration occurs and involves chemical reactions breaking down glucose, converting it into large amounts of ATP. The cells then release the energy from the molecules to continue cellular activity. Energy is transferred from sunlight in the photosynthesis process through the cellular membrane of the plants, with in the chloroplasts. As light energy and H2O react they create oxygen, along with ATP and NADPH. The ATP's and NADPH's then move along to the Calvin cycle where the introduction of CO2 with create sugar or it creates ADP +P as well as NADP+ on its way back to the light reaction phase. This whole process can create up to 36 ATP's. (Editorial Board, 2012)

2. Fermentation is also known as anaerobic respiration where the absence of oxygen is present. The only goal of the fermentation process is the conversion of NADH to NAD+. An example of the fermentation process in humans lactic acid build up in muscles after exercise when the body uses energy rapidly and can't get rid of the lactic acid build up fast enough. That's when you get muscle fatigue and you get the feeling of muscle aches.

3. Enzymes are needed to start or jump start reactions with in the cells. Enzymes are the molecules responsible for controlling cellular reactions. In fact there are hundreds if not thousands of different enzymes with in cells do to the amount of diverse reactions with in them. The 3 main steps of enzyme interactions are, one where the substrates enter the active site in a certain orientation. The second is the substrates and the active site change the shape which promotes a reaction between the substrates. The third is where the substrates bonded together and leave the substrate making it ready for a new set of substrates.