AP Exam Review Flashcards
Atomic number
Protons + electrons
Atomic mass
Protons + neutrons (make up the nucleus)
Ionic bonds
1 or more electron is transferred from 1 atom to another
Covalent bonds
Atoms share 1 pair of valence electrons
Changes in # of different particles
Change in electron # -> same element, different charge / bonding behavior
Change in proton # -> different element
Change in neutron # -> isotope
Electron movement from 1 shell to another
Electron moves closer to nucleus -> energy is released
Electron moves away from nucleus -> energy is stored
Compound
Substance with 2 or more different elements in a fixed ratio (ie, table salt = Na:Cl 1:1)
Element
Substance that can’t be broken down into other substances through chemical reactions
Monosaccharide functions
- Available source of energy
- Transport sugar in animals because -OH groups are polar and dissolve easily in blood
Disaccharide functions
- Bonded through dehydration synthesis
- Transport sugar in plants because many -OH groups with electronegative oxygens make them dissolve in water
Polysaccharide examples + functions (animals)
Glycogen - stores glucose/sugar for later use
Polysaccharide examples + functions (plants / non-animals)
Amylose (plants) - stores polysaccharides in plants
Cellulose (plants) - structural, made of beta-glucose so can’t be broken down
Chitin (arthropods/fungi) - structural, same as cellulose but different organisms
Triglycerides
Long-term storage of energy due to CH bonds
Made of glycerol (3-carbon alcohol) at 1 end and 3 fatty acid, long carbon chains attached to it (can be saturated or unsaturated)
Terpenes
- Pigments like chlorophyll
- Nonpolar/hydrophobic tail anchors in the membrane
- Long chain of carbons w/ methyl groups
Prostaglandins
- Messengers
- Stimulate smooth muscle and vasodilation
- Uterine contraction
- Soluble in cell membrane
- Ring w/ 2 long carbon chains
Steroids
Made of rings (hexagons/pentagons) - includes reproductive hormones and cholesterol, which makes cell membranes flexible
Bonds between amino acids
2 amino acids can bind through dehydration synthesis
- Covalent bond forms between carbon of carboxyl group & nitrogen of amino group
- They bond front of first + rear of second
Protein folding
1) Sequence of amino acids depends on DNA sequence
2) Folding due to H-bond interactions (alpha helix / beta pleated sheet)
3) Tertiary - occurs when protein encounters water (hydrophobic on the inside, hydrophilic on the inside)
4) Different proteins may bind together
Blood pH regulation
Specific properties of water
1) High specific heat
2) Universal solvent
3) Polar molecule
4) Cohesion and adhesion (capillary action / surface tension)
Isotope
Different version of an element
Same: element, # of electrons, # of protons, atomic number, atomic properties
Different: atomic mass, # of neutrons
Isomer
Compounds with the same number of the same atoms, but arranged differently (ie, C6H12O6 can form glucose or sucrose)
Na+/K+ pump steps
1) There is lots of Na+ (sodium) outside the cell and lots of K+ (potassium) inside the cell (resting state)
2) 3 Na+ ions from the cytoplasm bind to the sodium-potassium pump
3) The pump is phosphorylated, leading to a conformational change in which it loses affinity for the Na+ currently bound
4) The 3 Na+ ions (that were just bound) are released outside (against concentration gradient)
5) The new shape has a high affinity for K+
6) 2 K+ bind from the outside of the cell, causing the phosphate group to detach
7) The protein undergoes another conformational change in which it has a low affinity for K+
8) The K+ currently in the pump are then released, going into the inside of the cell (against concentration gradient)
9) Affinity for Na+ is high again -> cycle repeats
6 types of membrane proteins
1) Cell identity markers - glycoproteins, glycolipids, establish self v. other
2) Cell-cell adhesion proteins - help 2+ cells adhere to each other and pack tightly (ie, epithelial tissue)
3) Enzymes - catalyze reactions happening in the membrane
4) Gates - selectively allows molecules to enter
5) Receptors - receives to a hormone/ neurotransmitter
6) Proteins that attach to cytoskeleton - gives cell structure ie, actin and microtubules
4 kinds of signaling
1) Paracrine - cells communicate locally through the intercellular / interstitial fluid; involves mast cells which spread the message
2) Contact-dependent - cell membranes must be touching to communicate
3) Neuronal - occurs between neurons & target cells, similar to paracrine but no mast cell
4) Endocrine - long-distance, hormones travel in the bloodstream
Cytolysis
Plant cell bursts
Plasmolysis
Plant cell shrinks
Exergonic reactions
- Energy leaves
- Negative Gibbs free energy (-ΔG)
- Energetically favorable
- Spontaneous - the reaction can proceed on its own, but would take so long that enzymes are needed
- Products have less free energy than reactants
Energy coupling
Energy produced by exergonic reactions drive endergonic ones (ie, ATP drives photosynthesis)
Activation energy
Amount of energy required to strain reactant molecules so that bonds break and reaction can occur (needed to start both exergonic and endergonic reactions)
Cofactor/coenzyme
Cofactor: Any nonprotein molecule that an enzyme needs in order to function permanently (ie, zinc)
Coenzyme: A cofactor that is an organic molecule (ie, vitamins)
Endergonic reactions
- Energy is stored as molecules become more complex / ordered
- Enthalpy increases
- Positive Gibbs free energy (+ΔG)
- Products have more free energy than reactants
