Unit 3 Flashcards
Enzymes
Protein substances that speed up chemical reactions
Active Site
The specific portion of an enzyme that attaches to the substrate by means of weak chemical bonds
Substrate
A specific reactant acted upon by an enzyme
Enzyme substrate complex
a temporary molecule formed when the substrate binds to the enzyme.
Activation energy
Energy needed to get a reaction started
Biological catalyst
an enzyme
speeds up rate of a specific chemical reaction
Enzyme transition state
the intermediary state of the reaction, when the molecule is neither a substrate or product.
Denaturation
the unfolding or breaking up of a protein, modifying its standard three-dimensional structure
pH
scale to specific acidity and basicity
Acid
7>
Base
7<
Kinetic theory
a theory that states that all matter is composed of particles in motion and that the rate of motion varies directly with the temperature.
Kinetic energy
The energy of motion
Rate of reaction
speed at which a chemical reaction takes place
Competitive inhibitor
A substance that reduces the activity of an enzyme by entering the active site in place of the substrate whose structure it mimics
Noncompetitive inhibitors
A substance that reduces the activity of an enzyme by binding to a location remote from the active site, changing its conformation so that it no longer binds to the substrate
Allosteric site
site of bonding that is not for the typical substrate
is a regulatory site on a protein that can affect its activity
Coenzymes
an organic molecule that binds to the active sites of certain enzymes to assist in the catalysis of a reaction
1st law of thermodynamics
Energy is neither created nor destroyed, but may be converted from one form to another
2nd law of thermodynamics
When energy is changed from one form to another, some useful energy is always degraded into lower quality energy (usually heat)
Energy coupling
The use of an exergonic process to drive an endergonic one
ATP and ADP
ATP: helps fuel the light independent reactions, and are created by the light dependent reactions
ADP: product of calvin cycle, later used for light dependent reactions
NAD+ and NADH
NAD + is formed in aerobic respiration by a fermentation process and formed in anaerobic respiration by oxidation of NADH
molecules produced by the Krebs Cycle that go on to donate electrons in oxidative phosphorylation.
NADP+ and NADPH
NADP+: product of calvin cycle, later used for light dependent reactions
NADPH: helps fuel the light independent reactions, and are created by the light dependent reactions
Reactant
a substance that changes in a chemical reaction
Product
substance that results from a chemical reaction
Oxidation and reduction
Oxidation: A chemical reaction that involves the loss of an electron. Oxidation often involves the addition of oxygen and the loss of hydrogen ions
Reduction: The gain of electrons by a substance involved in a redox reaction (the charge of the substance becomes more negative)
Phosphorylation
the addition of a phosphoryl (PO3) group to a molecule
Endothermic
a chemical or physical process that absorbs heat from its surroundings
Exothermic
Chemical reactions that release energy
Photosynthesis
autotrophs use sun’s energy, CO2 and H2O to make glucose (C6 H12 O6) and oxygen
Chlorophyll
light-absorbing pigment that captures the energy of photons from the sun; found in photosystems 1 and 2
Chloroplast
carbon fixation happens there
Photosystem 1
energy arrives and joins the pair of chlorophylls in reaction center, electron is boosted and then transferred to acceptor molecule. missing electron from chlorophylls is replaced by new electron from ps2
Photosystem 2
light is absorbed here and then passed by pigements until it reaches the reaction center and the energy is transferred to ps1.. splits water and creates O2
gets new electrons from water
Electron transport chain
a series of proteins and organic molecules found in the inner membrane of the mitochondria. Electrons are passed from one member of the transport chain to another in a series of redox reactions. Energy released in these reactions is captured as a proton gradient, which is then used to make ATP
Electrochemical gradient
determines the direction that ions will flow through an open ion channel and is a combination of two types of gradients: a concentration gradient and an electrical field gradient.
Proton gradient
gradient of proton distribution
Chemiosmosis
A process for synthesizing ATP using the energy of an electrochemical gradient and the ATP synthase enzyme.
Inorganic phosphate
play a vital role in synthesizing biomolecules such as ATP, phospholipids, and DNA.
ATP Synthase
an enzyme that catalyzes the formation of ATP from ADP and inorganic phosphate
Light dependent reaction
happens in chloroplasts in the thylakoid membranes
basically just photosynthesis
Light independent reaction
Calvin Cycle
in stroma of chloroplast
fixation of carbon, reduction and regeneration
Calvin Cycle
light independent reactions
Cellular respiration
a metabolic pathway that uses glucose to produce adenosine triphosphate (ATP), an organic compound the body can use for energy. One molecule of glucose can produce a net of 30-32 ATP.
Fermentation (lactic acid and alcohol)
Lactic acid fermentation is mainly of anaerobic respiration
a biological process by which sugar is converted into alcohol and carbon dioxide.. anaerobic process
Aerobic
with air, glucose into energy
Anaerobic
without air, glucose into energy
Oxidative phosphorylation
The total process of ATP production including the electron transport chain and chemiosmosis
Glycolysis
Anaerobic process in which glucose is broken down into two molecules of pyruvate and two net ATP (makes a total of 4 ATP) and 2 NADH are produced
Pyruvate
a three-carbon acid that is naturally formed during glycolysis
Mitochondria
produces atp
Cytosol
glycolysis happens here
Krebs cycle
produces energy as ATP
The cycle starts with a three-carbon molecule, that is, pyruvic acid, which is further divided into acetyl coenzyme A which then combines further with oxaloacetic acid to generate citric acid. The end product of the Krebs cycle is an organic acid found in citrus fruits like lemons, oranges, etc. known as citric acid.
Electron transport chain
a series of proteins and organic molecules found in the inner membrane of the mitochondria. Electrons are passed from one member of the transport chain to another in a series of redox reactions. Energy released in these reactions is captured as a proton gradient, which is then used to make ATP
Inner mitochondrial membrane
carries out electron transport
Fitness (evolutionary fitness)
how good a particular genotype is at leaving offspring in the next generation
