Energy
How do enzymes work?
They stabilize transition products to lower activation energy
Where does glycolysis occur?
In the cytoplasm
What is the role of chlorophyll in photosynthesis?
When light strikes chlorophyll, it excites chlorophyll's electrons, releasing them to move through the electron transport chain
Why does ice float?
Water is more dense as a liquid due to crystalline structure formed by hydrogen bonds when water is a solid.
(1) shape (2) negative charge and/or polarity
What is the "purpose" of the krebs (citric acid) cycle?
To "charge up" the electron carriers NAD+ and FAD to NADH and FADH2, so that they can donate electrons to the electron transport chain
What is the role of Rubisco in the Calvin Cycle?
Rubisco performs "carbon fixation" by attaching inorganic CO2 from the atmosphere to an organic molecule (RUBP) in the plant.
Definition of Apoptosis
An exergonic process such as ATP hydrolysis or the oxidation of an electron carrier is used to drive endergonic processes like building large, complex molecules from simpler ones.
What is the purpose of electron flow in the electron transport chain
to pump hydrogen ions (protons) into the mitochondria's intermembrane space, creating electrochemical gradient that will later be used to power ATP synthase
Why do the "light independent reactions" still mostly happen during the day?
They require ATP and NADPH, which are produced by the light-dependent reactions
Theory that explains why some organelles have DNA. You need: (1) name of theory (2) description of theory (3) which organelles have DNA
(1) Endosymbiotic Theory
(2) Some organelles were once independent prokaryotes that were absorbed and entered into symbiotic relationships with larger prokaryotes
(3) mitochondria and chloroplasts
Describe two types of enzyme inhibition
Competitive inhibition: inhibitor binds to active site. Non-competitive inhibition: inhibitor binds to allosteric site, causing active site to change shape and lose affinity for substrate.
Oxygen consumption would increase, since more electron flow would be required to maintain the H+ gradient. ATP production would decline, since the H+ ions could cross into the mitochondrial matrix without passing through ATP synthase
Why are ATP and NADPH necessary for photosynthesis?
They transfer energy from the light-dependent reactions to the calvin cycle
Specific thing broken when secondary structure is disrupted
Hydrogen bonding
Explain why high substrate concentration is can overcome competitive inhibition, but not non-competitive inhibition
high substrate concentration means there is a greater likelihood that a substrate, and not a competitive inhibitor, will bind to the enzyme's active site. This has little effect on non-competitive inhibition because if the active site is "shut down" by a non-competitive inhibitor, the substrate cannot bind, no matter how much is present.
Why is lactic acid produced when oxygen is not present?
Fermentation must be used to supply NAD+ to glycolysis, which is how ATP is generated in the absence of oxygen
Describe the electron transport chain in photosynthesis
(1) When light strikes the chlorophyll in photosystem 1, it donates an electron to NADP+, reducing it to NADPH. (2) The electrons lost by PS1 chlorophyll are replenished by light striking PS2 chlorophyll. (3) the electrons lost by PS2 chlorophyl are replenished by H2O being stripped of electrons and converted to O2 by PS2. (4) Electron flow from PS2 to PS1 powers an H+ pump that pumps H+ ions into the thylakoid, creating a concentration gradient (5) These ions flow down the concentration gradient into the stroma through ATP synthase, generating ATP. In the end ATP and NADPH are produced, which are necessary for the Calvin Cycle.
When a ligand binds to a receptor, what happens?
-transduction
-amplification
-effect (change to gene transcription, etc.)