Biomolecules Atoms & Molecules

Flashcards about Biomolecules, Atoms, and Molecules

Atom

Single unit made up of neutrons, protons, and electrons

Molecule

Groups of 2+ atoms held together by chemical bonds due to electron interactions

Macromolecules

Large molecules (polymers) formed from the bonding of smaller molecules (monomers)

Ionic Bonds

Transfer of e- from one atom to another atom of very different electronegativity

Covalent Bonds

Sharing of e- between atoms of similar electronegativities

Nonpolar Bond

Equal e- sharing

Polar Bond

Unequal e- sharing, forms dipole

Hydrogen Bonds

Weak bond between a hydrogen atom and an electronegative atom (F, O, or N)

Dehydration Reaction

Links monomers to form polymers, forming H2O in the process

Hydrolysis

Uses water to break polymers into monomers

Monomer of Proteins

Amino acid

Polymer of Proteins

Peptide

Linkage type among Proteins

Peptide bonds

Function of Proteins

Structure, transport, defense, storage, enzymes

Monomer of Carbohydrates

Monosaccharide

Polymer of Carbohydrates

Polysaccharide

Linkage type among Carbohydrates

Glycosidic

Function of Carbohydrates

Store energy

Monomer of Lipids

Hydrocarbons

Polymer of Lipids

Hydrocarbon chain

Linkage type among Lipids

Covalent carbon-carbon

Function of Lipids

Insulation, energy storage, endocrine signaling, cell structure

Monomer of Nucleic Acids

Nucleotide

Polymer of Nucleic Acids

Nucleic acid (DNA, RNA)

Linkage type among Nucleic Acids

Phosphodiester bond

Function of Nucleic Acids

Encode, express, and store genetic info

Monosaccharides

Single sugar molecule (e.g., Glucose)

Disaccharides

2 joined sugar molecules (e.g., Glucose + Fructose = Sucrose)

Polysaccharides

Polymer of sugar molecules. Includes starch (α-glucose), glycogen (α-glucose), cellulose (β-glucose), chitin (β- glucose)

Triglycerides

Glycerol + 3 fatty acids

Phospholipids

2 fatty acids + phosphate group attached to glycerol backbone. Are amphipathic with polar head, nonpolar tail. Form phospholipid membrane bilayer

Steroids

Three 6-membered rings + one 5-membered ring. E.g., hormones, cholesterol

Porphyrins

4 joined pyrrole rings with a metal center atom. E.g., chlorophyll, hemoglobin

DNA

bases are A, T, C, G. Contains deoxyribose sugar and 2 complimentary antiparallel (5’ to 3’) strands of double helix. A and T pair via 2 H-bonds C and G pair via 3 H-bonds ↑ GC base pairs = ↑ H-bonds = ↑ temp to split strands. RNA has bases A, U, C, and G, with a ribose sugar and is single stranded

Chargaff’s Rule

A & T, and G & C are always present in equal amounts (i.e., if DNA is 20% A, it is also 20% T)

Primary Protein Structure

Linear chain sequence of amino acids

Secondary Protein Structure

Local folding of chain into α-helices/β-sheets via H-bonding between amino & carboxyl groups of adjacent amino acids

Tertiary Protein Structure

3D shapes due to noncovalent interactions between R groups (disulfide bonds are covalent exceptions)

Quaternary Protein Structure

3D protein shape consisting of 2+ separate peptide chains