INTRODUCTION TO BIOCHEMISTRY AND THE CELL

Comprehensive vocabulary flashcards covering introductory biochemistry, chemical bonding, biomolecules, and the structures and functions of prokaryotic and eukaryotic cells.

Biochemistry

The study of chemical processes within and relating to living organisms, focusing on the composition, structure, reactions, and processes of living cells.

Molecule

A group of two or more atoms held together by chemical bonds; it is the smallest basic unit of a pure substance that keeps its physical and chemical traits.

Chemical bonds

An enduring attraction between atoms, ions, or molecules that enables the formation of chemical compounds.

Ionic bonding

A type of chemical bond where an electron is transferred from one atom to another, resulting in an electrical attraction between ions.

Covalent bonding

A type of chemical bond where atoms share electrons.

Metallic bonding

A type of chemical bond where ions are surrounded by free electrons.

Molecular bonding

A type of chemical bond where a weak electrical attraction binds molecules together.

Inorganic molecules

Chemical structures that typically do not contain both carbon and hydrogen atoms together.

Biomolecules (Organic Molecules)

Carbon-based chemical structures typically containing carbon-hydrogen bonds ($C-H$) that serve as the foundation of all known life; the four major types are carbohydrates, lipids, proteins, and nucleic acids.

Carbohydrates

Organic molecules composed of $C$, $H$, and $O$ that serve as a short term energy source; they are joined by glycosidic bonds and include examples like starch, glycogen, and cellulose.

Proteins

Organic molecules composed of $C$, $H$, $O$, $N$, and $S$ that function in structure, movement, defense, and as enzymes; they are joined by peptide bonds and include examples like insulin and collagen.

Nucleic acids

Organic molecules composed of $C$, $H$, $O$, $N$, and $P$ that store genetic information; they are joined by phosphodiester bonds and include $DNA$ and $RNA$.

Lipids

Organic molecules composed of $C$, $H$, and $O$ used for long term energy, insulation, and membrane components; they are joined by ester bonds and include oils, fats, and waxes.

Monosaccharides

The monomers or basic building blocks of carbohydrates.

Amino acids

The monomers or basic building blocks of proteins.

Nucleotides

The monomers or basic building blocks of nucleic acids.

Fatty acids and glycerol

The components that serve as the monomers for lipids.

Water

The most common inorganic liquid on Earth that supports cell functions and body chemistry.

Salts

Ionic compounds that break down into charged particles (ions) in water.

Acids and Bases

Substances that control the $pH$ balance by releasing or accepting hydrogen ions.

Simple Gases

Basic molecules containing single elements or simple carbon forms without carbon-hydrogen chains, such as $CO_2$, $NH_2$, and $O_2$.

Cells

The basic unit of life; though structures and functions vary, they often share common characteristics.

Anabolism

A metabolic process of the cell that focuses on building up molecules.

Catabolism

A metabolic process of the cell that focuses on breaking down molecules.

Plasma membrane

The outermost selectively permeable layer of the cell composed of proteins, lipids, and carbohydrates that separates intracellular and extracellular substances.

Hydrophobic

A term describing the water-repelling regions of the phospholipid bilayer in the cell membrane.

Hydrophilic

A term describing the water-loving regions of the phospholipid bilayer in the cell membrane.

Nucleus

A large membrane-bound structure usually located near the center of the cell that acts as the location of $DNA$.

Gene

A region of a $DNA$ molecule that specifies an $RNA$ molecule.

Chromosomes

Thread-like structures of $DNA$ and proteins in the nucleus containing genetic information; humans contain $46$ total ($23$ from each parent).

Trisomy 21

A genetic condition in which an individual has an extra chromosome.

Nucleoli

Diffuse bodies inside the nucleus without a surrounding membrane where ribosomal $RNA$ is produced.

Cytoplasm

The material located outside of the nucleus and inside of the plasma membrane.

Ribosomes

The site of protein synthesis within the cell; they can be found attached to the Endoplasmic Reticulum or free in the cytoplasm.

Rough Endoplasmic Reticulum

A series of membranes with attached ribosomes that serves as the site for protein production and modification.

Smooth Endoplasmic Reticulum

A series of membranes without ribosomes involved in lipid synthesis and detoxification.

Golgi Apparatus

The packaging and distribution center of the cell that modifies proteins and lipids by attaching lipids and carbohydrates to them.

Secretory Vesicles

Small membrane-bound sacs pinched off from the Golgi apparatus that transport and store materials.

Lysosomes

Membrane-bound vesicles containing hydrolytic enzymes that function as the cell's intracellular digestive system.

Autophagy

The process by which lysosomes digest the cell's own organelles when they are no longer functional.

Peroxisomes

Small membrane-bound vesicles containing enzymes that break down fatty acids, amino acids, and hydrogen peroxide ($H_2O_2$).

Hydrogen Peroxide ($H_2O_2$)

A byproduct of fatty acid and amino acid breakdown that can be toxic to the cell.

Proteasomes

Large protein complexes containing enzymes that digest specific proteins.

Mitochondria

Known as the powerhouse of the cell, it is the major site for $ATP$ ($Adenosine\,Triphosphate$) synthesis.

$ATP$ ($Adenosine\,Triphosphate$)

The main energy source for most chemical reactions within the cell.

Cytoskeleton

A structure consisting of protein that supports the cell, holds organelles in place, and enables shape changes.

Centrosomes

The center of microtubule formation within the cell.

Microtubules

Hollow structures that support cytoplasm, assist in cell division, and form essential components of cilia and flagella.

Cilia

Slender protuberances projecting from the cell surface that move substances over the surface.

Flagella

Lash-like appendages that are longer than cilia and are used to propel sperm cells.

Microvilli

Small, non-moving structures that increase cell surface area to aid in absorption.

Prokaryotic Cells

Cells such as bacteria that lack a nuclear membrane, generally lack membranous structures (except mesosomes), and have simple flagella.

Eukaryotic Cells

Cells found in animals and protozoa that possess a nuclear membrane, membranous structures, and complex cilia or flagella structures.