Biochemistry Chapter 5 Quiz

A reaction that releases free energy, and proceeds spontaneously.

A reaction that absorbs free energy, and is not spontaneous.

The initial energy needed to start a chemical reaction.

Describes whether a reaction occurs spontaneously or not, and releases or requires energy.

A chemical agent that speeds up a reaction without being consumed.

A catalytic protein that speeds up reactions.

A reaction that occurs without any external input of energy, and proceeds on its own.

The intermediate state in a reaction, during which bonds are being broken and formed.

The breakdown of ATP (adenosine triphosphate) into ADP (adenosine diphosphate) and inorganic phosphate, releasing energy.

Using the energy released from an exergonic reaction to drive an endergonic reaction.

The addition of a phosphate group to a molecule.

The reactant that an enzyme acts on.

The specific region on an enzyme where the substrate binds.

The change in shape of an enzyme's active site as a substrate binds, improving binding and catalysis.

The temporary complex formed when an enzyme binds to its substrate.

The three main types of work performed by cells: chemical, transport, and mechanical.

The point at which all enzyme molecules are active and working at maximum speed.

The breakdown of glucose into two pyruvate molecules.

A small amount of ATP produced directly during glycolysis and the citric acid cycle.

Process generating most ATP during cellular respiration, powered by redox reactions.

Conversion of pyruvate to Acetyl CoA, linking glycolysis to the citric acid cycle.

Completes the breakdown of glucose.

Phase of glycolysis where energy is used to rearrange the glucose molecule.

The process of breaking down fats in the gut into absorbable components.

Phase of glycolysis where energy is released, producing ATP and NADH.

Overall process of harvesting energy from glucose.

Cholesterol-like molecules that break down fat globules, making fats accessible to enzymes.

An enzyme that breaks down triglycerides into fatty acids and monoglycerides.

Water-soluble particles that transport absorbed fats (triglycerides) from the gut to other tissues.

Lymphatic vessel in the small intestine villus, absorbing chylomicron-containing lymph.

Major form of fat storage in the body, especially in adipose tissue.

Process of absorbing digested fats (fatty acids, monoglycerides) into epithelial cells.

Tissue that stores triglycerides as fat globules, providing energy reserve.

The diffusion of water across a selectively permeable membrane from an area of high water concentration to an area of low water concentration.

The ability of a surrounding solution to cause a cell to gain or lose water.

A solution where the solute concentration is the same inside and outside the cell, resulting in no net water movement.

A solution with a higher solute concentration than inside the cell, causing water to leave the cell.

A solution with a lower solute concentration than inside the cell, causing water to enter the cell.

Passive transport of molecules across a membrane with the help of transport proteins.

A transport protein that provides a corridor allowing specific molecules or ions to cross the plasma membrane.

A plant cell in a hypotonic solution that has swelled until the cell wall resists further water uptake, becoming firm.

The primary pigment in photosynthesis, absorbing primarily red and blue light, reflecting green light.

An accessory pigment that absorbs primarily blue and orange light, reflecting green light, slightly different in structure from chlorophyll a.

Accessory pigments that absorb primarily blue and green light, reflecting yellow, orange, and red light. They also function in photoprotection.

A graph showing the wavelengths of light absorbed by a pigment.

A graph showing the rate of photosynthesis at different wavelengths of light.

A complex of proteins and pigments that capture light energy, consisting of a reaction-center complex and light-harvesting complexes.

The core of a photosystem, containing special chlorophyll a molecules and a primary electron acceptor, where light energy is converted to chemical energy.

A part of a photosystem that surrounds the reaction-center complex, containing pigments that absorb light and transfer energy to the reaction center.

A molecule in the reaction-center complex that receives excited electrons from chlorophyll a, initiating the flow of electrons in photosynthesis.

The absorption spectrum shows the wavelengths of light absorbed by pigments, while the action spectrum shows the rate of photosynthesis at different wavelengths. The action spectrum is broader than the absorption spectrum because accessory pigments contribute to photosynthesis.