FR Chap 7-8 Cell Respiration and Photosynthesis Flashcards
CELL RESPIRATION - Aerobic vs. Anaerobic?
Cellular respiration is an aerobic process, meaning that it requires oxygen. Fermentation makes ATP without using oxygen (anaerobic).
CR General equation (what are the reactants the products)?
C6H12O6 + O2 ->-> CO2 + H2O + about 38 ATP
glucose, oxygen, carbon dioxide, water, energy stored in ATP
Glycolysis
The first stage in breaking down a glucose molecule, called glycolysis, takes place outside the mitochondria in the cytoplasm of the cell. The word glycolysis means “splitting of sugar.” A cell invests two ATP molecules to break down glucose. The products of glycolysis are two pyruvic acid molecules, two NADH molecules and four ATP molecules.
The Krebs Cycle
Glycosis produces two pyruvic acid molecules from one glucose molecule. Each pyruvic acid molecule is converted to one acetyl CoA molecule. Since each turn of the Krebs cycle breaks down one acetyl CoA molecule, the cycle actually turns twice for each glucose molecule, producing a total of four carbon dioxide molecules & two ATP molecules.
Electron transport system
The electron carriers pass the electrons on to other carriers in a series of transfers called the electron transport chain. Each carrier holds the electrons more strongly than the carrier before it. At the end of the chain, oxygen–the electron grabber–pulls electrons from the final carrier molecule and joins them with hydrogen ions, forming water.
Fermentation (Lactic acid vs. Alcoholic)
Fermentation makes ATP without using oxygen. Cellular respiration still continues, but it is not the main source of ATP while fermentation is occurring. Fermentation in muscle cells produces a waste product called lactic acid. Fermentation in yeast produces ethyl alcohol.
PHOTOSYNTHESIS - Chloroplast & its structures
The cellular organelle where photosynthesis takes place is called a chloroplast. The chloroplast’s structure is key to its function. Like a mitochondrion, a chloroplast has an inner and an outer membrane. The inner membrane encloses a thick fluid called stroma. Suspended in the stroma are many disk-shaped sacs called thylakoids.
Photosynthesis general equation (what are reactants the products)?
CO2 + H2O ->->-> CGH12O6 + O2
Carbon dioxide, water, glucose, oxygen
Autotrophs vs. heterotrophs?
An organism such as a plant that makes its own food is called an autotroph, which means “self-feeder” in Greek. Organisms that cannot make their own food, such as humans, are heterophs, meaning “other eaters.”
Light Reactions (reactants and products)
The light reactions convert light energy to the chemical energy of ATP and NADPH.
Calvin Cycle (reactants and products)
With each turn of the Calvin cycle, there are chemical inputs and outputs. The inputs are carbon dioxide from the air and the ATP and NADPH produced by the light reactions. The cycle’s output is G3P.
