The Chemistry of Life (U3) Flashcards
Element
a basic substance made of only one kind of atoms
Compound
a substance of two or more elements combined
What are the 4 elements that make up 96% of biological matter?
Carbon, oxygen, hydrogen, nitrogen
Atom
Made of a nucleus of protons and neutrons surrounded by electrons that orbit in rings
Atomic number
the number of protons in an atom
Mass number
the number of protons and neutrons in an atom
Valence electrons
the electrons in the atom’s outermost shell
How do you find valence number?
elements in the same column have the same valence number and similar chemical properties
Electron configuration
atoms tend to complete or empty a partially filled valence shell - this drives chemical reactions and create bonds
Non-polar covalent bond
pairs of electrons are shared equally between two atoms
Polar covalent bond
pairs of electrons are shared unequally between two atoms, creating a charge
Ionic bond
the transfer of valence electrons between atoms
Intermolecular bonds
bonds between molecules
Intramolecular bonds
bonds within molecules (between atoms)
Hydrogen bond
when hydrogen bonds with highly electronegative atoms, provides structure and stability
Water molecules
+H attracted to -O, a “sticky” molecule
What are the five properties of water?
cohesion and adhesion, ability to dissolve substances, high specific heat, high heat of vaporization, and ability of ice to float in water
Cohesion
hydrogen bonding between H2O molecules
Adhesion
hydrogen bonding between H2O and other substances
Capillary action
the movement of water through the use of cohesion and adhesion
Solvents
dissolve solutes creating solutions
Universal solvent
water due to its polarity
Hydrophillic
substances with attraction to water (polar molecules)
Hydrophobic
substances that don’t have an attraction to water (non-polar molecules)
Hydrocarbon
any combination of hydrogen and carbon atoms, sable, hydrophobic, and gas at room temp
Carbon atoms
versatile building blocks, can form 4 stable covalent bonds
Isomer
molecules with the same molecule formula but different structures
Hydroxyl
-OH, alcohols
Carbonyl adehyde
-C=O at the end
Carbonyl ketone
-C=O in the middle
Carboxyl
-COOH, fatty and amino acids
Amino
-NH2, amines (compounds) that act as a base
Sulfhydryl
-SH, thiols, stabilize proteins with disulfide bridges
Phosphate
-PO4^2-
What are the four major macromolecule classes?
carbohydrates, lipids, nucleic acids, and proteins
Dehydration synthesis
condensation reaction, a polymer is formed by removing H2O monomers, requires energy and enzymes
Hydrolysis
digestion, breaking down of a polymer by removing one monomer at a time, releases energy
What are carbohydrates made of?
monomers that are sugars, classified by the number of carbons, for energy storage and structure
Glycosidic linkage
when two monosaccharides are bonded together during dehydration synthesis
Starch vs. cellulose
starch is easy to digest whereas only bacteria can digest cellulose
Starch vs. glycogen
starch is plants and glycogen is animals
Fats
HC tail and carboxyl head, protect, insulate, and store energy
Phospholipids
fatty acid tails and PO4 head, creates cell membranes
Steroids
4 fused carbon rings with functional groups, create animal cell membranes
Ester linkage
the bond between OH and COOH in lipids
Saturated fats
long straight chains, solid at room temp, contributes to cardiovascular disease
Unsaturated fats
kinks in chains due to double bonds, liquid at room temp
Nucleic acids
store and transfer genetic information
RNA
single helix (ribonucleic acid)
DNA
double helix (deoxyribonucleic acid)
Nucleotides
made of nitrogen base, pentose sugar, and phosphate group
Phosphodiester bond
bond in nucleic acids between sugar and PO4
Purine
double ring nitrogen base (adenine and guanine)
Pyrimidine
single ring nitrogen base (cytosine, thymine, and uracil)
Replication
the copying of DNA
Proteins
structurally and functionally diverse (enzymes, structure, carriers, cell communication, defense, movement, and storage)
What are the 4 major components of an amino acid?
central carbon, amino group, carboxyl group, R group
