1.4

Question 1

name the types of intermolecular forces that are NONCOVALENT

Answer 1

ionic interactions = opp charged ions

van der walls= interaction due to dipoles

Question 2

name the types of van der walls

Answer 2

hydrogen bonding like dipole dipole interactions (polar and polar), dipole induced (can cause induction of dipole of neighboring like ch3 and make it not distrib which the methyl being less nonpolar and polar) and London dispersion(nonpolar molecules only!) which has small dipole because of fluctuations….

Question 3

hydrophobic effect

Answer 3

the exclusion of nonpolars from polar to maximize the entropy of water molecules

Question 4

atomic distances are measured as?

Answer 4

angstrom (A) = 10^-10 m

Question 5

which has the highest bond strength? covalent or non covalent?

Answer 5

covalent

Question 6

despite being weak, why are London dispersion important?

Answer 6

interactions for making nonpolar substances liquid temp like benzene

Question 7

electroneg

Answer 7

atom attracts a shared pair of electrons toward itself

Question 8

electrostatic polarization

Answer 8

electro neg btwn atoms in coval bond but are not evenly distr which causes dipoles to form (charge separation)

Question 9

hydrogen bonding

Answer 9

• basically van der walls
• hydrogen bonded to oxygen or nitrogenwhich causes greater the direction and dipole
• nitrogen is electropos
• oxygen is electroneg
• makes water a liq at room temp?

Question 10

why is water highly polar?

Answer 10

it can be a proton donor or acceptor

Question 11

van der walls radius of h20?

Answer 11

1.4 angstrom

radius is btwn the center and the envelope

Question 12

van der walls of H

Answer 12

1.2 angstrom

Question 13

how many degrees is water shape?

Answer 13

104 degrees

Question 14

van der walls envelope

Answer 14

outer boundary of the cloud of electrons

Question 15

concave vs convex

Answer 15

degree < 180 is convex

deg > 180 is concave

Question 16

what happens with ice bonding?

Answer 16

it is structurally ordered with hydrogen bonds, static (doesn’t move) but it can form 4 bonds with other water molecules because it has tetrahedra shape

Question 17

densities of ice and water

Answer 17

ice = 0.92 g/ml
water= 1.00 g/ml

Question 18

liq water

Answer 18

loose h bonds that fluctuates and tumbles on a picometer
bonds to mers(3,4,5 water molecules) but it is not a permanent bonding. they are transient because they often break

bonds are held more TIGHTLY THAN ICE

Question 19

H2O is aka

Answer 19

universal solvent

Question 20

y can water dissolve polar substances

Answer 20

b/c its dipole character can weaken attractive opp charges molec like salt water

Question 21

aggregate

Answer 21

can still go in water but cannot easily dissolve in it like oil and lipids

• nonpolar rather stick to each other to minimize contact with water, SA, and loses less entropy
• NONPOLAR MOLEC form non homogenous droplets

Question 22

hydration

Answer 22

water molec neutralizes the charge of an ion

Question 23

amphillic molecules

Answer 23

homogenous but do not dissolve but disappear into solution

hide their hydrophobic but expose their hydrophilic

Question 24

amphi

Answer 24

both

Question 25

phillia

Answer 25

attraction

Question 26

nam 4 aggreg of artif synthetic membrane systems

Answer 26

micelles bicelles liposomes nanodisks

Question 27

diff btwn micelles and others

Answer 27

only one with monolayer

Question 28

describe micelles

Answer 28

sphere shape, detergent sds is in it, single tailed can have a central cavity filled with water depending on concen of detergents heads are polar so it protecs nonpol and is on outside of sphere

Question 29

biceles

Answer 29

disk like shape b/c there is too much crowding, two dif length of tails, tails form lipid bilayer NOT B/C OF TAILS

Question 30

liposome

Answer 30

3d structure with a single bilayer with central aqueous cavity - really a disrupted bicelle - delivery of hydrophilic drugs and nutrients in the central cavity b/c it doesn't readily diffuse

Question 31

nanodisks

Answer 31

``` has msp (membrane scaffold amphiathic proteins) that protect the outer tails -best for stabilizing/ folding proteins ```

Question 32

nanodisks vs bicelles

Answer 32

bicelles have a poor 3d structure that is heterogenous

Question 33

what do the integral membrane proteins do?

Answer 33

they penetrate the lipid bilayer and laterally swim across -form alpha or beta with hydrophobic surfaces -hydrophobic, non transmembrane,non soluble and precipitates out

Question 34

lateral vs transverse

Answer 34

lateral is fast and moves within same leaflet | transverse (rare) is slower and moves between the the inner and outer leaflet

Question 35

inner vs outer leaflet

Answer 35

inner is the leaflet on the cytoplasmic side whereas the outer leaflet is on the outside of the cell

Question 36

diff btwn the motion of heads and tails

Answer 36

the tails can move around and are more fluid but the heads are more restricted and cannot move bc unfavorable

Question 37

what is the fluidity of the lipid bilayer dependent on?

Answer 37

temp and lipid composition

Question 38

transition temp

Answer 38

phase transition in vitro from a liquid sol to a liquid crystal

Question 39

temp above tm

Answer 39

too fluid and mobile cholesterol decreases the fluidity by interrupting space of lipid tails

Question 40

temp below tm

Answer 40

gel like solid of ordered array increases the bilayer fluidity by interrupting the close packing of the tails

Question 41

cholesterol

Answer 41

fluidity buffer to respond to temp to help the tm

Question 42

peripheral membrane proteins (pmp)

Answer 42

water soluble and deals with lipid heads | transmembrane and can go from inner to outer leaflet vice versa

Question 43

beta barrel transmembrane

Answer 43

- forms closed hollow tunnel - ex:omPf - passage of nutrients, salts, and water

Question 44

alpha helical transmembrane

Answer 44

- transverse through bilayer once or more | - responsible for signal transduction and energy

Question 45

polar heads are aka

Answer 45

non transmembrane

Question 46

pmp are responsible for

Answer 46

signaling and shape of mosaic fluid model allows attachment of spectrin actin and ankyrin to the inner leaflet for membrane skeleton

Question 47

types found on inner leaflet

Answer 47

sphingomyelin and phosphotidycholine

Question 48

types found on outer leaflet

Answer 48

phosphotidyethanolamino and phosphatidyserine

Question 49

3 types of transverse diff

Answer 49

1. flippase (move from outer to inner leaflet with ATP) 2. floppase (inner to outer leaflet with ATP) 3. scramblase (bidirectional of leaflets without atp but to meach for equilib)