Biology Chapter: Enzymes and Sugars

A biological catalyst produced by living cells that speeds up the rate of a chemical reaction by lowering the activation energy.

The minimum amount of energy required by a reactant (substrate) to start a chemical reaction.

A specific site on an enzyme where the substrate binds.

A change in the shape of an enzyme, often caused by extreme temperatures or pH, that makes it lose its ability to function.

A model of enzyme action where the substrate fits perfectly into the active site of the enzyme.

The molecule upon which an enzyme acts.

The model that describes how an enzyme's active site changes shape to fit the substrate.

Factors that influence the rate of enzyme-catalyzed reactions, such as temperature, pH, and substrate concentration.

A group of hydrophobic molecules that are insoluble in water. They are primarily composed of carbon and hydrogen atoms with a small amount of oxygen.

A type of lipid that is the most abundant in the body. It's composed of one glycerol molecule and three fatty acid chains.

A 3-carbon alcohol with three hydroxyl groups. It's soluble in water.

Long chains of carbon atoms with a carboxyl group at one end. They can be saturated (no double bonds) or unsaturated (have double bonds).

A type of lipid that is a major component of cell membranes. It's an amphipathic molecule, meaning it has both hydrophilic (water-loving) and hydrophobic (water-fearing) parts.

A type of lipid that includes cholesterol, hormones, and vitamins. They have a characteristic four-ring structure.

A group of compounds composed of amino acids linked together by peptide bonds. They play a vital role in various biological functions, including building and repairing tissues, transporting substances, and catalyzing reactions.

Amino acids that cannot be synthesized by the body and must be obtained through diet or supplements.

Sugar molecules with a carbonyl group located at the end of the carbon chain. Examples include glucose.

Sugar molecules with a carbonyl group located in the middle of the carbon chain. Examples include fructose.

Sugars containing 3 carbon atoms. Examples include glyceraldehyde and dihydroxyacetone.

Sugars containing 5 carbon atoms. Examples include ribose, ribulose, and deoxyribose.

Sugars containing 6 carbon atoms. Examples include glucose and fructose.

A nitrogenous base found in both DNA and RNA, pairing with thymine (T) in DNA and uracil (U) in RNA.

A molecule consisting of two nucleotides joined together by a phosphodiester bond.

The process of joining multiple nucleotides together to create a long chain (polynucleotide).

A structural component of DNA, characterized by a double helix formed by two polynucleotide chains held together by hydrogen bonds.

Guanine, Adenine, Thymine, Cytosine are the four nitrogenous bases found in DNA.

RNA is a single-stranded molecule that carries genetic information from DNA to ribosomes for protein synthesis.

A process that breaks down a polypeptide into individual nucleotides.

The specific pairing of nitrogenous bases in DNA — adenine pairs with thymine (A-T), and guanine pairs with cytosine (G-C).

The type of bond that holds amino acid residues together in a polypeptide chain. It forms by a reaction between the carboxyl group of one amino acid and the amino group of another.

The four levels of protein structure: primary, secondary, tertiary, and quaternary. These levels describe the organization and folding of a protein from its linear sequence of amino acids to its complex 3D shape.

The first level of protein structure, describing the linear sequence of amino acids in a polypeptide chain.

The second level of protein structure, characterized by local regular patterns formed by hydrogen bonding. Common forms include alpha helices and beta sheets.

The third level of protein structure, describing the overall three-dimensional shape of a protein. This is influenced by interactions between amino acid side chains.

The fourth level of protein structure, formed when multiple polypeptide chains assemble together to create a functional protein complex.

Proteins that are generally elongated, insoluble in water, and play structural or mechanical roles in cells and tissues.

Proteins that are generally spherical, soluble in water, and often involved in catalysis, transport, and other dynamic processes.