Biology 161 Chemistry of Life and Organic Molecules

Vocabulary flashcards covering atomic structure, chemical bonds, biomolecules, gene expression, and energy transfer concepts from Biology 161 lecture notes.

Atomic Number

The number of protons in an atom's nucleus, which identifies the element.

Ion

An atom or molecule that has gained or lost electrons, giving it an uneven number of protons and electrons.

Cation

An ion with an overall positive charge, formed by losing negatively-charged electrons.

Anion

An ion with an overall negative charge, formed by gaining negatively-charged electrons.

Ionization

The process of a neutral atom gaining or losing an electron.

Voltage

The separation of charged particles across a distance or membrane.

Current

The flow of charged particles.

Ionic Bond

A chemical bond formed when two oppositely charged ions are attracted to one another, such as in table salt ($\text{NaCl}$).

Covalent Bond

A chemical bond formed by two or more atoms sharing electrons, such as in $\text{O}_2$.

Nonpolar Covalent Bond

A type of covalent bond where electrons are shared equally between atoms, such as in $\text{CO}_2$.

Polar Covalent Bond

A type of covalent bond where electrons are shared unequally, such as in water where oxygen hogs the electrons.

Hydrogen Bond

A weak attraction between a partially positive hydrogen atom and a partially negative region of a neighboring molecule without sharing electrons.

Organic Molecules

Molecules containing carbon, categorized into carbohydrates, lipids, proteins, and nucleic acids.

Monomer

A singular molecular unit that acts as a building block of a polymer.

Polymer

A large molecule containing many repeating molecular units called monomers.

Glycogen

A carbohydrate polymer that serves as the storage form of carbohydrates in animals.

Primary Structure

The specific sequence or string of amino acid monomers that makes up a protein before folding.

Gene Expression

The regulated physiological process of producing proteins from DNA through transcription and translation.

Transcription

The process of creating an RNA working copy of a gene using the nucleotide sequence of a DNA strand.

Translation

The process of reading an RNA nucleotide sequence to place amino acids in the correct order to form a protein's primary structure.

Triglycerides

A category of lipids consisting of three fatty acid tails linked to a glycerol backbone, functioning in energy storage and insulation.

Saturated Fats

Lipid chains containing only single covalent bonds between carbon atoms with as many hydrogen atoms as possible, commonly found in meats and dairy products.

Unsaturated Fats

Lipid chains containing one or more double covalent bonds with fewer hydrogen atoms, commonly found in oils, fish, and avocados.

Phospholipids

Lipids that form cell and organelle membranes, composed of two hydrophobic fatty acid tails and a phosphate-containing hydrophilic polar head group attached to glycerol.

Steroids

Large lipid molecules composed of a characteristic four-ring carbon structure without fatty acid tails, synthesized from cholesterol.

Hormone

A chemical messenger that travels slowly through the blood to send signals from one cell to another.

ATP (Adenosine Triphosphate)

A specialized nucleotide that functions in energy transfer within the body.

ATP Hydrolysis

The process of splitting ATP with water to yield ADP (adenosine diphosphate) and inorganic phosphate, resulting in the release of unstable free energy.