Macromolecules, Energy, and Chemical Reactions

Vocabulary flashcards covering nucleic acids, protein structures, bioenergetics, thermodynamics, and types of chemical reactions based on lecture notes.

Phosphodiester bond

A polar covalent bond that connects phosphate groups to form the backbone of a single strand of nucleic acid.

Nucleotide

The monomer of nucleic acids, composed of a phosphate group, a sugar (ribose or deoxyribose), and a nitrogenous base.

Hydrogen bond

A weak bond that holds the two complementary strands of DNA together between their nitrogenous bases.

Thermocycler

A machine that uses temperature cycles to heat DNA, break hydrogen bonds between strands, and make copies of DNA.

Collagen

The most common protein in the human body, found in skin and bones.

Peptide bond

The polar covalent bond that links amino acid monomers together to form proteins.

Glycoprotein

A protein with attached sugar groups that serves functions in cell signaling and immune system self-recognition.

Primary structure

The linear sequence of amino acids in a protein, held together by covalent peptide bonds.

Secondary structure

The folding pattern of a protein into alpha helices or beta pleated sheets, stabilized by hydrogen bonds.

Tertiary structure

The three-dimensional spatial shape of a protein resulting from hydrophobic and hydrophilic interactions of R groups with the surrounding environment.

Denaturation

The process by which a protein loses its conformational shape and function due to factors like heat or pH changes breaking its hydrogen bonds.

Potential energy

Stored energy, such as energy held in chemical bonds, high-energy electrons, or concentration gradients across membranes.

Kinetic energy

The energy of motion or energy actively being used to perform work.

First law of thermodynamics

The law stating that energy can neither be created nor destroyed, only converted from one form to another.

Second law of thermodynamics

The law stating that when energy is converted from one form to another, some energy is lost as heat.

Metabolism

The sum of all chemical reactions that occur within the body.

Catabolism

Decomposition or hydrolytic reactions that break larger molecules down into smaller components, releasing energy.

Anabolism

Synthesis or dehydration reactions that build larger molecules from smaller components, requiring an input of energy.

Oxidation

A chemical reaction in which a molecule or atom loses an electron.

Reduction

A chemical reaction in which a molecule or atom gains an electron.

Exergonic reaction

A chemical reaction that releases energy and occurs spontaneously.

Endergonic reaction

A chemical reaction that requires an input of energy to proceed.

Activation energy

The amount of energy required to initiate or trigger a chemical reaction.

Enzyme

A biological catalyst made of protein that decreases the activation energy required for a chemical reaction.