bio-100
in which examples does a vitamin or mineral function as a cofactor?
DNA polymerase requires zinc to replicate DNA hydroxlase enzyme require vitamin C during collagen synthesis
what is a vitamin?
an organic compound obtained in the diet that is required for normal metabolism?
which of these describes a catabolic pathway?
a pathway that breaks down molecules into smaller subunits
which of these describes an anabolic pathway?
a pathway that generates molecules from smaller subunits
how do chlorophyll pigments absorb energy from light?
a photon excites an electron in the chlorophyll to a higher energy state
which of the statements describe photosynthesis?
converts carbon dioxide to sugars, releasing oxygen is a cellular process that occurs in the chloroplasts of plant cells produces sugars for the plant using the energy from sunlight
what does the law of conservation of energy state?
energy cannot be either created or destroyed, but it can be transformed
classify each phrase as describing an enzyme an active site or a substrate.
enzyme: a biological catalyst a protein containing an active site active site: a specific enzyme location that binds with the substrate substrate: a substance that the enzyme acts upon may be a phosphate group
how do enzymes catalyze reactions?
enzymes bind with and change the conformation of substrates
which describes how cofactors and coenzymes affect the function of enzymes?
increase catalytic function
what provides the energy that excites the electrons in the chlorophyll molecules? what is the source of the electrons that replace the excited electrons lost from chlorophyll?
light / sunlight H2O
classify each of the names and statements that describe the essential nutrients as belonging to either the macronutrient category or the micronutrient category.
macronutrients: required in large amounts main components of organic molecules phosphorus(P) / nitrogen(N) carbon(C) micronutrients: required in small amounts mainly enzyme cofactors chlorine(Cl) iron(Fe) / manganese(Mn)
which choices are considered essential nutrients in the human diet?
minerals, essential fatty acids, vitamins
select all of the statements that accurately describe photorespiration.
photorespiration the rate at which sugar is produced in the calvin cycle photorespiration is metabolically expensive photorespiration releases CO2
what is the primary role of water in photosynthesis?
the breakdown of water provides electrons and H+ ions for the light reactions
why does disrupting the calvin cycle impact the light reactions of photosynthesis?
the calvin cycle regenerates NADP+ the calvin cycle regenerates ADP
what is energy?
the capacity of a system to do work
choose the best description of kinetic energy
the energy an object has due to its motion / the energy an object has as a result of its own movement
which part of the graph represents activation energy? choose the best definition for activation energy.
D energy that must be added to start a reaction
identify whether the example describes an anabolic or catabolic pathway.
anabolic pathway: photosynthesis generates storage carbohydrates from CO2 and H2O a lipid molecule is constructed from fatty acid subunits catabolic pathway: glycolysis converts one molecule of glucose to two molecules of pyruvate a protein molecule is broken down into amino acid subunits
which of the statements correctly contrasts anabolic and catabolic pathways?
anabolic pathways are synthesis pathways, whereas catabolic pathways are degradation pathways
how do enzymes lower the activation energy of a reaction?
by forming a temporary bond between the active site and the substrate by producing conditions within the active site conducive to the reaction by stressing a bond in a substrate that needs to be broken
which substances are produced during photosynthesis in plants?
carbohydrates oxygen
which molecules are reactants in photosynthesis in plants?
carbon dioxide water
a specialized protein in saliva breaks up starch molecules in food into smaller chains of simple sugars. in this reaction, which molecule is the enzyme, which is the substrate, and which is the product?
enzyme: the specialized protein substrate: the starch molecules product; the small chains of simple sugars
which of the statements best describes the overall role of enzymes in metabolism?
enzymes increase the speed of reactions
how do enzymes affect the activation energy of a reaction? label the reaction energy diagram with the appropriate terms.
enzymes lower the activation energy longer line: activation energy without enzyme shorter line: activation energy with enzyme
suppose that you conduct an experiment to determine how photosynthetic output, measured in oxygen productions, changes as you alter photosynthesis, and generate the graph. identify which manipulations to photosynthesis generated the observed changes in O2 production depicted in the graph.
highest to lowest: high CO2 normal conditions high O2 green light high temperatures
activation energy is best defined as the energy that
is required to bring the reactant molecules to a transition state
what is the significance of a lower activation energy?
it increases the rate of a cellular reaction
which of the statements describes essential nutrients for the human body?
nutrients that the body cannot synthesize or does not produce in sufficient quantities
complete the photosynthesis reaction by placing the compounds and energy sources into the reaction as reactants or products.
photosynthesis reactants: carbon dioxide water light energy photosynthesis products: simple sugars oxygen not placed: hydrogen / nitrogen
which of the statements regarding potential energy is true?
potential energy is the energy that an object has based on its position
which of the statements describes heat?
the transfer of thermal energy from one body to another / the transfer of energy from a system with more thermal energy to a system with less thermal energy
which statement describes the function of photosynthetic pigments in leaves?
they capture light energy and remove electrons from a donor
