Introduction to energy and metabolism
The series of linked chemical reactions in a cell is called a _____ pathway.
Metabolic
ATP stands for _____.
Adenosine triphosphate
The waste product of aerobic respiration that plants use in photosynthesis is _____.
CO₂
The main two products of glycolysis are 2 ATP and 2 molecules of _____.
pyruvate
In fermentation, cells regenerate _____ so glycolysis can continue.
NAD⁺
Catabolic pathways usually _____ energy, while anabolic pathways consume it.
Release
The high-energy bonds between phosphates in ATP are called _____ bonds.
Phosphoanhydride bonds
In glycolysis, glucose is split into two 3-carbon molecules of _____.
Pyruvate
Glycerol from triglycerides can enter metabolism after being converted into _____.
Dihydroxyacetone phosphate (DHAP)
What smelly gas is released when sulfate is reduced during anaerobic respiration? _____
Hydrogen sulfide (H₂S)
Reactions with ΔG > 0 that require energy input are called _____.
Endergonic
Enzyme activity can be affected by environmental factors such as _____ and _____.
Temperature and pH
The Krebs cycle occurs in which part of the mitochondrion? _____
The matrix
Where does pyruvate get converted to acety-CoA?
mitochondrial matrix
Which process provides only ~2 ATP per glucose but allows survival in oxygen-free environments? _____
Fermentation (anaerobic respiration)
The second law of thermodynamics states that energy transfers increase _____.
Entropy (disorder)
Vitamins often act as precursors to _____, molecules that help enzymes function.
Coenzymes
In the electron transport chain, oxygen combines with electrons and H⁺ ions to form _____.
Water (H2O)
Which type of molecule is broken down during β-oxidation? _____
Fatty acids
Name one alternative electron acceptor in anaerobic respiration besides nitrate.
Sulfate, iron (Fe³⁺), or CO₂
Living organisms are examples of _____ systems because they exchange both matter and energy with their surroundings.
Open
What happens to enzyme activity when the enzyme is denatured?
It loses its function (active site shape is disrupted)
Name the two reduced electron carriers that feed electrons into the ETC
NADH and FADH₂
Name one amino acid that can feed into the Krebs cycle as acetyl-CoA.
Leucine, isoleucine, lysine, phenylalanine, tryptophan, or tyrosine
Deep-sea hydrothermal vent ecosystems are powered by microbes that oxidize _____ compounds.
Inorganic (e.g., H₂S, Fe²⁺, NH₃)