Photosynthesis and Cellular Respiration Note-taking Guide Preview to Photosynthesis glucose, reactions, light-dependent, Calvin cycle, thylakoid, photosystem II, oxygen, light-harvesting, two, chloroplasts, photosynthesis, stroma, chemical The most important chemical equation for life in our planet is: Carbon dioxide + Water Energy Sugar +, a process that takes place in the leaf of plants, practically powers our whole planet! The process occurs in a series of complex. In green plants, photosynthesis occurs in the of leaves. Chloroplasts contain stacks of membranes in a fluid matrix called the. Thylakoid membranes are embedded with important complexes containing chlorophyll molecules, called photosystem I and. The process of photosynthesis occurs in main stages and in two different parts of a chloroplast. The first stage includes the reactions, which occur in the thylakoids of a chloroplast. In these reactions, energy from light is converted to energy. The second stage consists of the that takes place in the fluidic stroma of a chloroplast. 2011 2015 Edusmart 1
The Calvin cycle produces that stores energy produced by the light reactions. Photosynthesis Light-dependent Reactions oxygen, light reaction, proton, electron, NADPH, by-product, excited, chemiosmosis, hydrogen, ATP, transport chain, water, glucose When light energy reaches photosystem II, it causes an to get excited and leave the photosystem. To replace the electron lost by the chlorophyll molecule, a molecule is split. This water splitting reaction releases two electrons, two ions and an atom, which quickly combines with another oxygen atom to form a molecule of oxygen gas. The excited electron is then transported down an electron from photosystem II to photosystem I, to fill an electron "gap" in photosystem I. This electron gap is created when light energy reaches an electron in photosystem I and causes it to get and leave. The gap is then filled in by the excited electron from photosystem II. During the, electrons are excited and replaced continuously in this manner. This excited electron is transferred down another electron transport chain. Electrons transported this way are eventually added to NADP+ to produce. This is used in the Calvin cycle to synthesize. 2011 2015 Edusmart 2
Meanwhile, the H+ ions that build up in the thylakoid interior space create a gradient. The cell uses the energy in this gradient to drive the production of from ADP, with the help of an enzyme ATP synthase, in a process called. To sum up, the light reactions produce ATP and NADPH that are used in the Calvin cycle. Oxygen is a of these reactions. Photosynthesis Calvin Cycle organic, carbon dioxide, hydrogen, ATP synthase, energy, NADPH, Calvin cycle, glucose, stroma, two In contrast to the light-dependent reactions, the does not require light. Molecules of enter the cycle, and are incorporated into organic molecules already present in the of a chloroplast. The cycle proceeds through a series of reactions that ultimately give rise to 3-carbon sugars that join to form a 6-carbon molecule. The compound is then returned to the cycle. from ATP is used to drive some of the reactions, converting ATP back to ADP. Molecules of ADP are returned to, to be converted back into ATP. Electrons and ions from NADPH are also incorporated into these reactions. 2011 2015 Edusmart 3
This converts the to NADP+ molecules, which are once again available to accept new high-energy electrons from photosystem I. Cellular Respiration pyruvate, fermentation, protein, carbon dioxide, cytoplasm, respiration, inner membranes, aerobic, ion, chemiosmosis, mitochondria, carbon, hydrogen, energy, Kreb s cycle, electrons, cytoplasm, oxygen, water, reactions, chemical, anaerobic, ATP synthase Glucose is used up by plant and animal cells to provide. Glucose is broken down, with the help of, to release carbon dioxide, water, and energy. The process of cellular transfers chemical energy from glucose to molecules of ATP that provide energy for cellular processes. Like photosynthesis, cellular respiration does not proceed in a single step. It is also a complex series of that happen in stages. The process occurs in the cytoplasm and of plant and animal cells. The main stages of cellular respiration are: Glycolysis The citric acid cycle, also known as the Electron transport and Glycolysis occurs in the of a cell. The splitting of 6-carbon glucose into 3- carbon molecules releases energy, which drives a reaction that forms ATP from ADP. 2011 2015 Edusmart 4
In the Kreb s cycle, which occurs in the mitochondrial matrix, pyruvate enters the mitochondrial matrix to go through a series of reactions that result in the loss of atoms. These carbon atoms are combined with oxygen and are released as. These reactions also remove which are carried by electron acceptor molecules NADH and FADH2 to the electron transport chain. The energy released by breaking down pyruvate is used to drive a reaction that forms ATP from ADP. Mitochondria are filled with folds of. Electron transport occurs in complexes embedded in these membranes. Electrons harvested from the breakdown of glucose are sent through an electron transport chain and their energy is used to pump H+ ions from one side of the membrane to another, forming an gradient. As with photosynthesis, energy in the ion gradient is used to form ATP from ADP by chemiosmosis, with the help of. This stage produces the bulk of the ATP molecules formed during cellular respiration. Meanwhile, the electrons from the electron transport chain combine with ions in the mitochondrial matrix, and an oxygen atom, to form a molecule of. This form of cellular respiration, in the presence of oxygen is called respiration. Sometimes, as in the case of strenuous exercise, muscle cells don't get enough oxygen. At these times, the process of cellular respiration ends with the breakdown of glucose into pyruvate molecules in the. 2011 2015 Edusmart 5
This is called respiration or lactic acid. It yields only two ATP molecules, far less than aerobic respiration. Comparing Photosynthesis and Cellular Respiration products, photosynthesis, releases, reactants, light, cellular respiration, energy These two cell processes, photosynthesis and cellular respiration, provide chemical for nearly all of Earth s organisms. The of photosynthesis are the products of cellular respiration, and the of photosynthesis are the reactants of cellular respiration. In, small inorganic molecules are converted to complex organic molecules. In, complex organic molecules are broken down to form simple inorganic molecules. Photosynthesis cannot occur without the input of energy from. On the other hand, cellular respiration energy. 2011 2015 Edusmart 6