Biology Chap9 Notes

Destiny Cobb Biology Chapter 9 pgs. 227-249

Main Idea Section 9.1 ATP in a Molecule

Notes/Vocabulary • ATP is the molecule that stores energy for easy use within the cell. • ATP is formed when a phosphate group is added to ADP. When ATP is broken down, ADP and phosphate is formed and energy is released. • ATP is the main link between energy-releasing and energy-using reactions. ATP (adenosine triphosphate)- energy-storing molecule in cells composed of an adenosine molecule, a ribose sugar and 3 phosphate groups; energy is stored in the molecule’s chemical bonds and can be used quickly and easily by cells

ADP (adenosine diphosphate)- molecule formed from the breaking off of a phosphate group for ATP; results in a large release of energy that is used for biological reactions • Photosynthesis is the process by which cells use light energy to make Section 9.2 carbohydrate. Photosynthesis: • Chlorophyll in the chloroplasts of plant cells traps light energy needed Trapping the for photosynthesis. Sun’s Energy • The light reactions of photosynthesis produce ATP and result in the splitting of water molecules • The reactions of the Calvin Cycle make carbohydrates using CO2 along with ATP and hydrogen from the light reactions. Photosynthesis- process by which autotrophs, such as algae and plants, trap energy from sunlight with chlorophyll and use this energy to convert CO2 and H2O into simple sugars -Equation for photosynthesis: 6CO2 + 6H2O = C6H12O6 + 6O2 (Carbon dioxide)(water) (glucose)(breathable oxygen) Light-dependent reactions- phase of photosynthesis where light energy is converted to chemical energy in the form of ATP; results in the splitting of water and the release of oxygen Light-independent reactions- phase of photosynthesis where energy from the light-dependent reactions is used to produce glucose and additional ATP molecules Pigments- molecule that absorb specific wavelengths of sunlight Chlorophyll- light-absorbing pigments in plants and some protist that is required for photosynthesis; absorbs most wavelengths of light except for green Electron transport chain- series of proteins embedded in a membrane along which energized electrons are transported; as electrons are passed from molecule to molecule, energy is released NADP+- (nicotinamide adenine dinucleotide phosphate) electron carrier

Destiny Cobb Biology Chapter 9 pgs. 227-249

molecule; when carrying excited electrons it becomes NADPH

Photolysis- reaction taking place in the thylakoid membranes of a chloroplasts during light-dependent reactions where 2 molecules of water are split to form oxygen, hydrogen ions, and electrons

Section 9.3 Getting Energy to Make ATP

Calvin Cycle- series of reactions during the light-independent phase of photosynthesis in which simple sugars are formed from carbon dioxide using ATP and hydrogen from the light-dependent reactions • Cellular Respiration is the process by which cells break down carbohydrates to release energy. • Cellular respiration takes place in mitochondria, uses oxygen, and yields many more ATPs than do anaerobic processes. • Energy can be released anaerobically by glycosis followed by alcoholic or lactic acid fermentation. Cellular Respiration- chemical processes where mitochondria break down food molecules to produce ATP; the 3 stages of cellular respiration are glycolysis, the citric acid cycle, and the electron transport chain Anaerobic- chemical reactions that do not require the presence of oxygen Aerobic- chemical reactions that require the presence of oxygen Glycolysis- in cellular respiration, series of anaerobic chemical reactions in the cytoplasm that break down glucose into pyruvic acid; forms a net profit of 2 ATP molecules. Citric acid cycle- in cellular respiration, series of chemical reactions that break down glucose and produce ATP; energies electron carriers that pass the energized electrons on to the electron transport chain Lactic acid fermentation- series anaerobic chemical reactions in which pyruvic acid uses NADH to form lactic acid and NAD+, which is then used in glycolsis; supplies energy when oxygen for aerobic respiration is scarce Alcoholic fermentation- anaerobic process where cells convert pyruvic acid into carbon dioxide and ethyl alcohol; carried out by many bacteria and fungi such as yeasts