matter & atoms
What 2 types of properties do elements have?
chemical and physical
What are the three types of chemical bonds?
covalent, hydrogen, ionic
what are the 4 main macromolecules?
carbohydrates, lipids, proteins, nucleic acids
In a drawing of an organic molecule, what does each dot represent?
dots = carbons. look at the number of bonds to see how many hydrogens are attached.
What is an organic molecule? What makes them?
compounds of carbon, living things/cells make them
What two things attract to form a hydrogen bond?
a partially negative charge on one molecule + the partially positive charge on H in another molecule
What is the structure and function of a phospholipid?
Phospholipids: components of the membrane
Components: Polar/hydrophilic head, nonpolar/hydrophobic fatty acid tails
What types of molecules are hydrophilic? Hydrophobic?
Nonpolar molecules and ions are hydrophobic - ex oil
Polar molecules are hydrophilic - ex water
What is an atomic nucleus composed of?
protons (+) and neutrons (=)
True or false. hydrocarbons are polar.
False - Hydrocarbons are Molecules made entirely of H and C. C-H bonds are nonpolar.
monosaccharides
What are the 4 components of an amino acid?
Carboxyl group, amino group, R group, Hydrogen
What determines if an atom is an ion? what are the 2 types of ions?
unequal number of electrons and protons
cations (+) and anions (-)
2 atoms have an electronegativity difference of 0.999. What type of bond do they have? Why not the other types?
they have a polar covalent bond - diff = 0.5 to 1.9
other bond types are nonpolar covalent (diff - 0 to 0.4), ionic bond (>1.9), and hydrogen bond (attraction)
What is the difference between saturated and unsaturated fatty acids?
Saturated: carbons are saturated with H atoms. NO double bonds C=C. results in linear shape, compact
Unsaturated: at least ONE double bond C=C. results in ‘kink’, results in more space
What are the 6 elements make up 98% of living matter?
Carbon (C)
Hydrogen (H)
Oxygen (O)
Nitrogen (N)
Phosphorus (P)
Sulfur (S)
What does the valence shell determine? How does it contribute to an atom being stable?
determines how an atom behaves; If the valence shell is full, the atom is stable and won't interact with other atoms
explain the relationship between polarity, electronegativity, and covalent bonds.
Covalent: atoms share one or more electron to fill valence shells
Polarity: e- shared unequally, property of having charged poles
Electronegativity: attractive force that an atom's nucleus exerts on electrons
The types of covalent bonds in a molecule determine polarity, NP vs P covalent bonds have different EN differences
Explain how monomers react to form polymers
Polymers are formed by dehydration (condensation) rxns - H2O removed
What are the 5 functions of proteins ?
Structural - cytoskeleton
Internal transport/movement - motor protein
Membrane transport - membrane associated
Catalyze chemical reactions - enzymes, sometimes membrane associated, some in cytoplasm
Cell-cell communication - receptors