AP BIOLOGY UNIT 3 QUESTIONS AND ANSWERS 100% COREECT
ANSWERS GRADED A+
ATP - (answer)(adenosine triphosphate) main energy source that cells use for most of
their work
ADP - (answer)adenosine diphosphate; molecule that ATP becomes when it gives up
one of its three phosphate groups
free energy - (answer)Chemical energy available to do work
substrate level phosphorylation - (answer)the enzyme-mediated direct transfer of
phosphate from another molecule (the substrate) to ADP
reduction - (answer)Gain of electrons by a chemical reactant; any reduction is
accompanied by an oxidation.
oxidation - (answer)Relative loss of electrons in a chemical reaction; either outright
removal to form an ion, or the sharing of electrons with substances having a greater
affinity for them, such as oxygen. Most oxidations, including biological ones, are
associated with the liberation of energy.
oxidized - (answer)loses electrons
reduced - (answer)gains electrons
NAD - (answer)nicotinamide adenine dinucleotide - a coenzyme that is an electron
carrier; NAD+ is oxidized, NADH is reduced
reducing agent - (answer)compound that loses electrons in a reaction
oxidizing agent - (answer)compound that gains electrons in a reaction
cellular respiration - (answer)The catabolic pathways by which electrons are removed
from various molecules and passed through intermediate electron carriers to O2,
generating H2O and releasing energy.
aerobic - (answer)Requiring molecular oxygen, O2
pyruvate oxidation - (answer)pyruvate molecules are oxidized and produces acetyl-CoA,
CO2, and NADH
citric acid cycle - (answer)In cellular respiration, a set of chemical reactions whereby
acetyl CoA is oxidized to carbon dioxide and hydrogen atoms are stored as NADH and
FADH2. Also called the Krebs cycle.
, energy-investing reactions - (answer)endergonic stage of glycolysis in which glucose is
converted into G3P
energy-harvesting reactions - (answer)exergonic stage of glycolysis in which G3P is
converted into two molecules of pyruvate
pyruvate - (answer)Three-carbon compound that forms as an end product of glycolysis.
NADH - (answer)reduced electron carrier molecule formed in glycolysis
Krebs cycle - (answer)another name for the citric acid cycle
acetyl CoA - (answer)molecule formed from the oxidation of pyruvate
FADH2 - (answer)a reduced coenzyme similar to NADH, an electron carrier
anaerobic - (answer)Occurring without the use of molecular oxygen, O2.
fermentation - (answer)Speaking specifically about energy metabolism, the anaerobic
degradation of a substance such as glucose to smaller molecules such as lactic acid or
alcohol with the extraction of energy. (2) Speaking generally, metabolic processes that
occur in the absence of O2.
lactic acid fermentations - (answer)Anaerobic series of reactions that convert glucose to
lactic acid, in some bacteria and animal cells.
alcoholic fermentation - (answer)Anaerobic series of reactions that convert glucose to
ethyl alcohol (ethanol) and carbon dioxide in some plants and yeast cells.
photosynthesis - (answer)photosynthesis: Metabolic processes carried out by green
plants and cyanobacteria, by which visible light is trapped and the energy used to
convert CO2 into organic compounds.
light reactions - (answer)The initial phase of photosynthesis, in which light energy is
converted into chemical energy.
pigment - (answer)A substance that absorbs visible light.
chlorophyll - (answer)Any of several green pigments associated with chloroplasts or
with certain bacterial membranes; responsible for trapping light energy for
photosynthesis.
absorption spectrum - (answer)A graph of light absorption versus wavelength of light;
shows how much light is absorbed at each wavelength.
ANSWERS GRADED A+
ATP - (answer)(adenosine triphosphate) main energy source that cells use for most of
their work
ADP - (answer)adenosine diphosphate; molecule that ATP becomes when it gives up
one of its three phosphate groups
free energy - (answer)Chemical energy available to do work
substrate level phosphorylation - (answer)the enzyme-mediated direct transfer of
phosphate from another molecule (the substrate) to ADP
reduction - (answer)Gain of electrons by a chemical reactant; any reduction is
accompanied by an oxidation.
oxidation - (answer)Relative loss of electrons in a chemical reaction; either outright
removal to form an ion, or the sharing of electrons with substances having a greater
affinity for them, such as oxygen. Most oxidations, including biological ones, are
associated with the liberation of energy.
oxidized - (answer)loses electrons
reduced - (answer)gains electrons
NAD - (answer)nicotinamide adenine dinucleotide - a coenzyme that is an electron
carrier; NAD+ is oxidized, NADH is reduced
reducing agent - (answer)compound that loses electrons in a reaction
oxidizing agent - (answer)compound that gains electrons in a reaction
cellular respiration - (answer)The catabolic pathways by which electrons are removed
from various molecules and passed through intermediate electron carriers to O2,
generating H2O and releasing energy.
aerobic - (answer)Requiring molecular oxygen, O2
pyruvate oxidation - (answer)pyruvate molecules are oxidized and produces acetyl-CoA,
CO2, and NADH
citric acid cycle - (answer)In cellular respiration, a set of chemical reactions whereby
acetyl CoA is oxidized to carbon dioxide and hydrogen atoms are stored as NADH and
FADH2. Also called the Krebs cycle.
, energy-investing reactions - (answer)endergonic stage of glycolysis in which glucose is
converted into G3P
energy-harvesting reactions - (answer)exergonic stage of glycolysis in which G3P is
converted into two molecules of pyruvate
pyruvate - (answer)Three-carbon compound that forms as an end product of glycolysis.
NADH - (answer)reduced electron carrier molecule formed in glycolysis
Krebs cycle - (answer)another name for the citric acid cycle
acetyl CoA - (answer)molecule formed from the oxidation of pyruvate
FADH2 - (answer)a reduced coenzyme similar to NADH, an electron carrier
anaerobic - (answer)Occurring without the use of molecular oxygen, O2.
fermentation - (answer)Speaking specifically about energy metabolism, the anaerobic
degradation of a substance such as glucose to smaller molecules such as lactic acid or
alcohol with the extraction of energy. (2) Speaking generally, metabolic processes that
occur in the absence of O2.
lactic acid fermentations - (answer)Anaerobic series of reactions that convert glucose to
lactic acid, in some bacteria and animal cells.
alcoholic fermentation - (answer)Anaerobic series of reactions that convert glucose to
ethyl alcohol (ethanol) and carbon dioxide in some plants and yeast cells.
photosynthesis - (answer)photosynthesis: Metabolic processes carried out by green
plants and cyanobacteria, by which visible light is trapped and the energy used to
convert CO2 into organic compounds.
light reactions - (answer)The initial phase of photosynthesis, in which light energy is
converted into chemical energy.
pigment - (answer)A substance that absorbs visible light.
chlorophyll - (answer)Any of several green pigments associated with chloroplasts or
with certain bacterial membranes; responsible for trapping light energy for
photosynthesis.
absorption spectrum - (answer)A graph of light absorption versus wavelength of light;
shows how much light is absorbed at each wavelength.
