chapter four - atoms to cells

Atom,Smallest unit of matter

Element,Pure form of matter composed of atoms of one single type

CHONPS,Carbon hydrogen oxygen nitrogen phosphorus and sulfur; these elements make up 98 percent of the mass of living organisms

Molecule,Combination of atoms

Organic molecule,Molecule that contains a carbon-carbon bond

Macromolecule,Large organic molecule

Carbohydrate,Macromolecule with many functions especially the production of short-term energy or ATP

Monosaccharide,Sugar such as glucose fructose or galactose

Disaccharide,Carbohydrate such as lactose maltose or sucrose

Polysaccharide,Carbohydrate such as glycogen cellulose or chitin

Lipid,Macromolecule that serves as a structural component of membranes and other cell parts and supplies long-term energy

Phospholipid,Lipid that makes up cell membranes

Phospholipid bilayer,Stable structure formed by phospholipids in bacterial and eukaryotic cell membranes

Protein,Chains of different amino acids that perform functions such as catalyzing biochemical reactions serving as receptors and transporters providing structure and aiding movement

Amino acid,Building block of proteins; 20 amino acids have different functional R groups

Primary protein structure,Linear sequence of amino acids

Peptide bond,Bond that holds amino acids together in the primary structure of a protein

Secondary protein structure,Specific spatial conformation of strands of a growing polypeptide into an alpha helix or beta-pleated sheet

Alpha helix,One form of secondary protein structure

Beta-pleated sheet,One form of secondary protein structure

Tertiary protein structure,Unique three-dimensional shape of the entire polypeptide formed by hydrogen and disulfide bonds

Quaternary protein structure,Stable functional complex formed when some proteins associate with other proteins; examples include hemoglobin and antibodies

Nucleic acid,Long chain composed of nucleotides

Nucleotide,Contains a five-carbon sugar a phosphate group and a nucleotide base

DNA,Deoxyribonucleic acid that encodes genetic information in genes

RNA,Ribonucleic acid involved in the transfer of information from gene to protein

DNA double helix,Double-stranded DNA consisting of sugar-phosphate backbones held together by nucleotide bases

DNA base pairing,A pairs with T and C pairs with G

mRNA,Messenger RNA transcribed from a gene; it is single-stranded and contains codons

tRNA,Transfer RNA that carries amino acids to mRNA and contains anticodons

rRNA,Ribosomal RNA that is part of a ribosome

Cell,Fundamental unit of life

Prokaryotic cell,Cell without a true nucleus or nuclear membrane and without membrane-bound organelles

Eukaryotic cell,Cell with a nucleus and other organelles

Cell envelope,Includes the plasma membrane cell wall and an outer membrane in Gram-negative species

Bacterial cell wall,Structure outside the cell membrane typically made of peptidoglycan

Peptidoglycan,Material that typically makes up the bacterial cell wall

Plasma membrane,Phospholipid bilayer with proteins that separates the cytoplasm from the outside environment

Gram-positive cell wall,Thick cell wall with multiple layers of peptidoglycan

Gram-negative cell wall,Thin cell wall with a single layer of peptidoglycan enclosed by an additional outer membrane

Outer membrane,Additional membrane exterior to the cell wall of Gram-negative bacteria

Murein lipoprotein,Protein of the outer membrane that bonds with peptidoglycan

Lipopolysaccharide (LPS),Large sugar and lipid molecule extending from the outer membrane

Ribosome,Structure present in bacterial cells

Flagella,Possible external appendages of bacterial cells

Pilus,Possible external appendage of bacterial cells