Sections I-IV Vocab

Question 1

hydrogen bonds

Answer 1

a hydrogen atom covalently bound to one electronegative atom also attracted to another electronegative atom

Question 2

Electronegativity

Answer 2

elements that differ in their affinity for electrons. Share electrons unequally

Question 3

Hydrophilic

Answer 3

form weak bonds to water molecules

Question 4

Synthesis

Answer 4

A reaction that increases the structural complexity. An example is polymerization.

Question 5

Polymerization

Answer 5

A large subset of group reactions

Question 6

Condensation-Dehydration

Answer 6

Two molecules combine and small molecules are lost

Question 7

Hydrolysis

Answer 7

Breakdown of an organic molecule by adding water H2O.

Question 8

Polysaccharides

Answer 8

100 to 1000 monosaccharides linked together

Question 9

Triglyceride

Answer 9

Three fatty acids linked to a glycerol molecule. Energy storage (fat),

Question 10

Phospholipid

Answer 10

Principal component of cell membranes. Two fatty acids and a polar head group.

Question 11

Peptide bond

Answer 11

amino groups joined together. the alpha amino group of one amino acid and alpha carboxyl group of a second.

Question 12

Primary structure

Answer 12

Sequence of amino acids in its polypeptide chain

Question 13

Secondary structure

Answer 13

Regular arrangement of amino acids. Localized regions of polypeptide: alpha helix and beta sheets

Question 14

Alpha helix

Answer 14

region of polypeptide chain coils itself, with the CO group of one peptide forming an h-bond with NH

Question 15

Beta sheets

Answer 15

two parts of a polypeptide chain lie side by side with hydrogen bonds between them

Question 16

Tertiary structure

Answer 16

Folding of a single polypeptide. Interaction of the side chains of amino acids that live in different regions of the primary sequence. Structures are called domains. Localization of hydrophobic AA’s in the interior of the protein and the hydrophilic amino acids on the surface

Question 17

Quaternary structure

Answer 17

Interactions between polypeptide chains in proteins composed of more than one polypeptide

Question 18

Oxidation

Answer 18

loss of electron density, loss of oxygen or hydrogen

Question 19

Reduction

Answer 19

gain of electron density, happens usually by gaining a hydrogen

Question 20

Free energy

Answer 20

changes in enthalpy and entropy. Predicts whether or not the rxn is energetically favorable.

Question 21

Activation energy

Answer 21

The energy required to reach the transition state. Role of an enzyme is to lower the activation energy by having multiple reactants come together.

Question 22

Allosteric modification

Answer 22

“other site”. enzyme activity is controlled by binding small molecules to regulatory sites on the enzyme. Consists of multiple subunits and worlds directly on the affected protein and is faster.

Question 23

Covalent modification

Answer 23

Needs to make the object before, turns it on and phosphorylates it. Longer lasting and less prone to fluctuation

Question 24

Peripheral (Extrinsic) Membrane

Answer 24

Proteins that dissociate from the membrane following treatments with polar reagents, such as pH or high salt concentrations. Soluble in aqueous solutions.

Question 25

Integral (Intrinsic) Membrane

Answer 25

Inserted into the lipid bilayer. Only broken down if the membrane is broken down by detergents.

Question 26

Fluid (Fluid Mosaic Model)

Answer 26

membrane held together mainly by hydrophobic interactions lipids and some proteins can drift laterally

Question 27

Mosaic (Fluid Mosaic Model)

Answer 27

Membrane is a collage of different embedded proteins

Question 28

Passive Diffusion

Answer 28

A molecule simply dissolves in the phospholipid bilayer, diffuses across it, and then dissolves in the aqueous solution on the other side. No energy is needed

Question 29

Facilitated Diffusion

Answer 29

Involves the movement of molecules in the direction determined by their relative concentrations inside and outside of the cell. No energy is needed. Ex - carrier proteins and channel proteins

Question 30

Active Transport

Answer 30

Energy is provided for maintaining gradients of ions across the plasma membrane. Example: Na+ - K+ pump

Question 31

Cotransport

Answer 31

type of secondary active transport; gradient established by Na+-K+ pump (animal cells). transports of other molecules coupled to movement down these gradients. Symport and Antiport.

Question 32

Channel

Answer 32

Form open pores in the membrane that allow small molecules of the appropriate size and charge to pass freely through the bilayer. They allow gases, hydrophobic molecules, small uncharged polar

Question 33

Carriers

Answer 33

Bind specific molecules to be transported on one side of the membrane. Undergo conformational changes that allow the molecules to pass through

Question 34

Pumps

Answer 34

Responsible for maintaining the gradients of ions across the plasma membrane provides

Question 35

Glycosaminoglycan (GAGs)

Answer 35

Hydrated gel due to the negative charge on the outside attracting positive ion molecules which attracts water. Resists compression forces.

Question 36

Proteoglycans

Answer 36

proteins and GAGs linked together. Creates hydrated gels in plant cells. Provides hydrated space and forms gels of varying pore size and charge density.

Question 37

Collagen

Answer 37

Rich in proline and glycine residues. Resists tensile forces.

Question 38

Elastin

Answer 38

Vertebrae tissues such as skin, blood vessels, and lungs. Needs to be both strong and elastic in order to function

Question 39

Fibronectin

Answer 39

Prototype adhesion proteins in all vertebrae

Question 40

Nuclear pore complex

Answer 40

Only channels through which small polar molecules, ions, and macromolecules (proteins, RNA) can go through. Composed of about 30 different pore proteins (nucleoporins). Molecules travel through by freely diffusing and facilitated diffusion

Question 41

NLS

Answer 41

Most often 1 or 2 short sequence rich in basic amino acids lysine and arginine

Question 42

Importin

Answer 42

Nuclear localization signals are recognized by nuclear transport receptors. Carries the proteins into the nucleus; regulated by Ran. Activity is regulated by GTP binding and hydrolysis

Question 43

Constitutive Secretion

Answer 43

All cells do this type of secretion. Happens a lot/ all the time. Secretion is constant

Question 44

Regulated Secretion

Answer 44

Regulated when it happens. Only secreted when it is needed