Chemistry of Life
The pH of a solution increases from 6 to 8. How does the hydrogen ion concentration change?
What is a decrease by a factor of 100?
The nitrogen bases adenine and thymine are held together by these bonds.
What are hydrogen bonds?
Under anaerobic conditions, muscle cells regenerate NAD⁺ by reducing pyruvate to this compound.
What is lactate?
When water molecules stick to other polar surfaces, the property is called what?
What is adhesion?
The α-helix and β-pleated sheet are examples of what level of protein structure?
What is secondary structure?
Water’s high specific heat capacity is due to this type of intermolecular attraction.
What are hydrogen bonds?
The bond formed between two monosaccharides is called what?
What is a glycosidic linkage?
The enzyme that fixes CO₂ in the Calvin cycle is also the most abundant protein on Earth.
What is RuBisCO?
In glycolysis, phosphoenolpyruvate transfers its phosphate group to ADP. This reaction is an example of what type of phosphorylation?
What is substrate-level phosphorylation?
The 20 amino acids differ in the structure of this component.
What is the R group (side chain)?
Hydrolysis reactions are the reverse of this type of reaction that forms macromolecules.
What is dehydration synthesis (condensation)?
The peptide bond forms between which two functional groups of adjacent amino acids?
What are the amino group (-NH₂) and the carboxyl group (-COOH)?
Noncompetitive inhibitors bind to this region on an enzyme, causing conformational change and reduced activity.
What is an allosteric site?
Enzymes change the rate of a chemical reaction by altering what aspect of the reaction?
What is the activation energy?
The peroxisome detoxifies hydrogen peroxide using this specific enzyme.
What is catalase?
You measure enzyme activity versus substrate concentration and find a plateau at high substrate levels. This indicates what kinetic property?
What is enzyme saturation (Vmax)?
In nucleic acids, purines pair with pyrimidines to maintain uniform width of the helix. Name both purines.
What are adenine and guanine?
The enzyme sucrase catalyzes the breakdown of sucrose but not lactose. This demonstrates what property of enzymes?
What is specificity?
Disulfide bridges form between these specific amino acid residues, contributing to tertiary structure stability.
What are cysteine residues?
A mutation that disables a cell’s lysosomal acid hydrolases will most directly disrupt which cellular process?
What is intracellular digestion or autophagy?
Cells often use the energy released from ATP hydrolysis to power processes that require energy, like active transport or building macromolecules. This linking of energy-releasing and energy-using reactions is known as what?
What are coupled reactions?
Nucleotides are linked together in nucleic acids by bonds between these two components.
What are the phosphate group and the sugar (phosphodiester bonds)?
The chemiosmotic gradient in chloroplasts is established across which membrane, and into which compartment do protons accumulate?
What is the thylakoid lumen?
Unsaturated fatty acids are liquid at room temperature because their double bonds cause this structural effect.
What is kinking (preventing tight packing)?
DNA and RNA differ by a single oxygen atom located on which carbon of the sugar molecule?
What is the 2' carbon?