AP Bio Practice Quiz: Test Your Knowledge

Mitochondria produce ATP through the process of cellular respiration, making them the powerhouse of the cell. Their inner membrane is specially adapted to facilitate this energy generation.

ATP (adenosine triphosphate) is the main energy carrier in the cell. It stores energy in its high-energy phosphate bonds, which can be released to fuel cellular activities.

The cell membrane is selectively permeable and controls the passage of substances in and out of the cell. Its lipid bilayer structure plays a key role in maintaining homeostasis.

Osmosis is the passive movement of water across a semipermeable membrane from areas of low solute concentration to high solute concentration. This process does not require energy.

Cells are the fundamental units of life, capable of performing all necessary life processes. Every living organism is composed of one or more cells.

The Electron Transport Chain (ETC) generates the majority of ATP during cellular respiration through oxidative phosphorylation. This process occurs in the inner mitochondrial membrane and utilizes a proton gradient for energy.

In the light-dependent reactions, water molecules are split (photolysis), and oxygen is released as a byproduct. This process is essential for converting solar energy into chemical energy.

Enzymes act as catalysts, increasing the rate of biochemical reactions by lowering the activation energy required. They do not alter the reaction equilibrium, only how quickly equilibrium is reached.

Simple diffusion is the passive movement of molecules down their concentration gradient without the need for energy input. It is a fundamental process that allows substances to spread evenly across a membrane.

In DNA, adenine pairs with thymine through two hydrogen bonds, ensuring proper base pairing. This complementary base pairing is vital for maintaining the structure and function of the DNA double helix.

Ribosomes are responsible for synthesizing proteins by translating mRNA into polypeptide chains. They are essential for translating the genetic code into functional proteins.

Crossing over occurs during prophase I of meiosis when homologous chromosomes exchange segments of DNA. This process increases genetic variation in the resulting gametes by shuffling alleles.

A mutation is any alteration in the nucleotide sequence of DNA. These changes can range from harmless to significant and may lead to variations in an organism's phenotype.

The citric acid cycle, also known as the Krebs cycle, occurs within the mitochondrial matrix. This compartment contains the enzymes necessary for the cycle's series of reactions that produce electron carriers.

Proteins, in the form of enzymes, are the catalysts that accelerate biochemical reactions within the cell. Their unique three-dimensional structures allow them to specifically interact with substrates.

The chemiosmotic theory states that the energy from the electron transport chain is used to pump protons across the mitochondrial membrane, creating an electrochemical gradient. The flow of protons back across the membrane powers ATP synthase to produce ATP.

Receptor proteins are embedded in the cell membrane and bind specific signaling molecules. Once activated, they initiate intracellular signaling cascades that regulate various cellular responses.

The hydrophobic nature of the active site helps to exclude water, which could interfere with substrate binding. This creates an environment that favors strong interactions with nonpolar regions of the substrate, optimizing catalysis.

Redundancy in the genetic code means that multiple codons can encode the same amino acid. This buffering effect minimizes the impact of point mutations, often preserving protein function despite small genetic changes.

A defect in the electron transport chain disrupts the normal flow of electrons, resulting in decreased ATP synthesis. This disruption also causes NADH to accumulate, which can further impair metabolic processes in the cell.