Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BCH4024 > Lipids by Ziele > Flashcards

Lipids by Ziele Flashcards

1
Q

what are the three roles of lipids

A

energy storage; structure; signaling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what percent of biological membranes are made up with structural lipids

A

50%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

why are lipids a good energy source

A

they can be packed very densely thus allowing a lot of energy to be stored within them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

describe the difference between human and plant energy consumption

A

plants cannot store energy as fat/ lipids and rely on carbohydrates which are not as energy dense and require water; therefore animals are able to move since they have larger stores of energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what part of the plant is rich in fat and why

A

seed because mobile

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

how do fatty acids act as neurotransmitters

A

they are secreted by the nervous system and bind to cannabinoid receptors to prevent activation of inhibitor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the basic lipid molecule and its two forms?

A

fatty acids: saturated (straight line, no double bonds) unsaturated (kinky, double bonds)

fatty acids begin with a carboxylic acid follow by carbon chains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what conformation do unsaturated fatty acid double bonds lie in

A

cis conformation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

describe the IUPAC naming of fatty acids

A

in front of the name, the number of carbons: number of double bonds (delta^position numbers of double bonds) cis- xyz

ex. 20:5 (delta ^ 5, 8, 11, 14, 17)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

describe the omega system of naming fatty acids

A

starting at the omega carbon (farthest from the alpha) count in until you hit your first double bond and the naming would be omega - #

ex. omega-6 if first double bond is at the sixth carbon with C1 being the omega carbon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

describe the phenomenon with melting point and saturated v unsaturated fatty acids

A

saturated fatty acids have a higher melting point than unsaturated fatty acids because of the

hydrophobic effect (fatty acids won’t come together as straight carbon chains)
van der Waals interactions (for saturated: strengthen interactions when close together and repel water/ melting)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is the trend for melting point and saturated fatty acids

A

as you increase the number of carbons, melting point increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the trend for melting point and unsaturated fatty acids

A

mp decreases as the number of double bonds increases
but increases with increasing C and not changing double bond amounts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

describe the solubility of saturated and unsaturated fatty acids

A

solubility rules some for both types; insoluble in water but soluble in organic solvent (ex. benzene)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are triacylglycerols (TAG)

A

aka triglycerides
3 fatty acids in ester linkage to glycerol
non polar, hydrophobic, neutral
function: fat storage for energy and heat production as well as thermal insulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are glycerophopholipids

A

structural lipid
2 fatty acids (U or S) with any alcohol head group, glycerol, and ester linkages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are sphingolipids

A

structural lipid
sphingosine (amino alcohol) + amide linked fatty acid + polar head group (glycosidic or phosphodiester bond)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are some common signaling molecules

A

cholesterol, prostaglandins (mediate swelling), cholesterol derived hormones (ex. cortisol)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

how can we attack esters?

A

hydrolysis to form carboxylic acid and alcohol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are the two major components of all membranes

A

lipids and proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what are some important properties of proteins? what allows these properties?

A

flexible, transport materials in and out, semi permeable self sealing

non covalent interactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are important characteristics of biological membranes

A

define external boundaries, control molecular traffic, divide cells/ organelles, organize reaction sequences, communication, transporters, receptors, adhesion molecules, and energy transduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is the thickness of membrane

A

50-80 angstrom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what do fatty acids/ lysolipids form in term of membranes

A

micelle with cone shaped subunits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what do glyserophospholipids and sphingolipids form in term of membranes

A

bilayer with cylindrical subunits and a vesicle in the inside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what can you use to open micelle

A

SOS/ detergent molecules 12C with sulfur head

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what are the protein components of membranes?

A
  1. integral membrane proteins
  2. peripheral membrane proteins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

descrive integral membrane proteins

A

monotopic or polytopic (thought one or both leaflets of bilayer)
removable only by hydrophobic agent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

describe peripheral membrane proteins

A

electrostatic/ hydrogen bonding, released by detergents or by interfering with charge
interact with hydrostatic interaction
stay in contact with another protein or heads on lipids, not attached

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

describe amphitropic proteins

A

interact reversibly with membrane; bound to membrane makes it inactive while activated when off

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what are the two techniques to study protein topology

A

in silico (analysis of primary amino acid sequence)
in vitro (determined experimentally)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what type of amino acids would be inside versus outside the cell or membrane

A

inside the cell would be hydrophobic AA
outside the cell would be hydrophilic (O/ N linked sugars)
inside the membrane is mostly non polar/ uncharged AA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

describe a type 1 (glycophorin) integral membrane protein

A

alpha helix structure with the amino terminus on the outside of the cell and the carboxyl terminus on the inside, goes through cell once

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

describe a type III integral membrane protein (bacteriorhodopsin)

A

multiple alpha helices in the membrane, amino terminus outside and carboxyl terminus on the inside
acts as a proton pump in archea that live in high salt, low O2 environments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what can be used to predict 3D structure of a membrane protein?

A

hydropathy index where delta G < 0 shows hydrophilic AA and delta G > 0 shows hydrophobic

36
Q

describe a hydropathy plot

A

residue number (x) v hydropathy index (y) shows areas of hydrophilicity and hydrophobicity

37
Q

describe topology rules

A

1) positive inside rule (+ charged amino acids on the inside of the cell)
2) high levels of tyrosine and tryptophan found at membrane interface (due to slight hydrophilicity bc of OH & NH and amphiphatic behavior )

38
Q

describe proteins with beta barrel structure

A

difficult to predict, have aqueous pore in center

39
Q

how can membrane proteins associate with membranes

A

by covalently attached lipids

40
Q

how can proteins be attached to a membrane post translation

A

carbon chain can be attached to a protein in order to target and attach that protein to the membrane

41
Q

describe a liquid ordered state (Lo)

A

when temperature is below the melting point and is rigid/ gel like/ stick of butter in the fridge (solid like but membrane is liquid ordered state)
NOT GOOD FOR BIOLOGICAL MEMBRANE

42
Q

when is a biological membrane healthy

A

being in a balanced fluid state with mix of saturated and unsaturated fatty acids; maintained between Lo and Ld

43
Q

describe a liquid disorder state (Ld)

A

complete fluid, not good

44
Q

how does the concentration of unsaturated and saturated acids change the membrane fluidity?

A

the more saturated fatty acids will increase the order/ rigidity of the membrane while unsaturated will increase the fluidity.

45
Q

describe uncatalyzed lateral diffusion

A

when a phospholipid goes from one area on its leaflet to another; very fast, dynamic

46
Q

describe uncatalyzed transbilayer (flip flop) diffusion

A

when phospholipids switch leaflets; very slow, not favorable since it pulls a hydrophilic head through hydrophobic legs

47
Q

describe catalyzed transbilyar translocations

A

using Flippase, Flooppase, or scamblase, phospholipids can change leaflets

48
Q

flippase moves phospholipids…

A

from the outer leaflet to the inner leaflet; uses ATP

49
Q

floppase moves phospholipids…

A

from the inside of the cell to the outside; uses ATP

50
Q

scramblase moves phospholipids…

A

across the leaflet down a gradient and doesn’t use ATP

51
Q

describe cholesterol

A

maintains membrane fluidity by having hydrophilic and hydrophobic regions and broadening/buffering the temperature range the membrane can handle

52
Q

describe simple diffusion

A

for small, non polar molecules (ex. O2 or NH3) based on concentration gradient

53
Q

describe facilitated diffusion

A

going down a concentration gradient but requires a transport protein (ex. glucose transporters)

54
Q

describe primary active transport

A

ex. flip flop; energy supplied to move something against concentration gradient; ATP hydrolysis occurs on transport

55
Q

describe secondary active transport

A

moving a solute against its concentration by using energy from a secondary source such as an ion moving in on its own concentration gradient

56
Q

describe ion channel

A

simple channels, similar to facilitated diffusion, highly specific for ions; gated mechanism; only move down concentration gradient

57
Q

describe ionophore

A

small molecules that mask charge of ion and move it down a gradient

58
Q

what is the relationship between Kt and affinity for a solute

A

the lower the Kt, the higher the affinity of a solute since the lower Kt means the less amount of time it took to reach V1/2max

59
Q

where are GLUT1 transporters

A

ubiquitous

60
Q

where are GLUT2 transporters

A

liver, pancreatic islets, intestine; where glucose gets stored as glycogen/ fat

61
Q

where are GLUT3 transporters

A

brain and testis, highest affinity for glucose since brain does not use fatty acids for energy

62
Q

where are GLUT 4 transporters

A

muscle, fat, heart
*insulin dependent
high glucose releases insulin which allow GLUT4 to be expressed; low glucose does not active GLUT4

63
Q

what is uniport v cotransport? symport v antipode?

A

U: one molecule one way
C: two molecules
S: same way 2 molecules
A: different ways 2 molecules

64
Q

describe chloride bicarbonate (anion) exchanger

A

CO2 + H2O -> carbonic anhydrase -> HCO3- + H+ + Cl-(from outside
* and produces reverse when moves down cell (via concentration gradient) and is in lungs
use exchanger to facilitate the conversion of CO2-> HCO3- -> CO2
occurs in red blood cell
anion (Cl-) comes in while HCO3- leaves or vice versa depending the area of the cell is in
antiporter
80% CO2 is transferred like this

65
Q

what is the equation for free energy change of transport

A

delta G = RT ln ( C2/C1)

OR

R = 8.314 J/molK
T = temperature
C1 = initial concentration on one side of membrane
C2 = final concentration on other side of membrane

dont worry about standard bc it would be zero if concentration 1 = C2

66
Q

when is delta G favorable/ unfavorable in transport energy context

A

delta G is not favorable/ + when going against/ low to high
delta G is favorable / negative when going with gradient (high to low)

67
Q

what is the delta g equation for a charged species

A

+ ZF(delta psi)

Z = charge of species
F = 96,480 J/Vmol
delta psi = membrane potential

68
Q

sign of delta psi depends on…

A

which way movement is occuring

in to out = (+) delta psi
out to in = (-) delta psi

69
Q

Describe the P-type ATPase

A

primary active transporters: type 3 transporter: E1 configuration without ATP; with ATP allows calcium to bind; 2 gated mechanism; reversibly phosphorylated by ATP at phosphorylation domain

70
Q

Describe ABC Transporter

A

ATP Binding Cassette
pump out of the cell
hydrolyzing ATP causes conformational cell to push molecule out
primary active transporter
ex. flip flop
used to get toxins out
ubiquitous

71
Q

Describer Na+ Glucose Symporter

A

secondary active transport; symport; moves glucose down Na+ gradient; need 2 Na per glucose to move it into the cell (glucose then uses GLUT2 to get into blood circulation); Na K ATPase bring Na into the cell, ATP used here to establish gradient

72
Q

what are the 4 general types of signal transduction

A
  1. G protein couple receptor
  2. receptor enzyme (tyr kinase)
  3. gated ion channel
  4. nuclear receptor - gene level
73
Q

what is the difference between contact dependent and contact independent signal transduction

A

contact dependent/ electrical synapses: need contact to pass; junction
contact independent: paracrine/ endocrine/ autocrine/ synaptic - dont need touch, just send it across

74
Q

describe the G protein coupled receptor (ex. beta adrenergic receptor)

A

1) cell receptor receives epinephrine binds
2) G protein, hombre causes GDP to be replaced with GTP and active protein causing a cascade of activated G proteins (amplification)
3) effector enzyme of ion channel (adenylyl cyclase forms cAMP which activates PKA to start cell response on epinephrine)

75
Q

Describe the Na+ K+ ATPase

A

3 Na+ out, 2 K+ in, 1 ATP used
maintains concentration of ions across membrane

76
Q

what happens when ABC Transporters are overstressed?

A

causes a fail in chemotherapy treatment for cancer
cells express MDR1 to spit out anti tumor drugs

77
Q

describe ion channels

A

single gate mechanism; highly selective; gating mechanism either voltage gated or ligand gated

78
Q

describe specificity in terms of characterization of signals

A

only signal molecule fits in its binding site

79
Q

describe amplification in terms of characterization of signals

A

enzymes active other enzymes in a cascade

80
Q

describe modularity in terms of characterization of signals

A

proteins have interchangeable parts (like legos) in order to bind to multiple different signals when they have multivalent affinities

81
Q

describe desensitization in terms of characterization of signals

A

receptor activation triggers feedback circuit that shuts off receptor

82
Q

describe integration in terms of characterization of signals

A

when two signals have opposite effects on the same factor, the response is the net change

83
Q

describe localized response in terms of characterization of signals

A

local and brief response when enzyme destroys a message from its producer

84
Q

describe the alpha beta and gamma subunits of G

A

alpha G is GTP binding domain and effector protein binding domain; G beta-gamma subunit holds the inactive alpha

85
Q

describe phospholipase c

A

another G protein effector enzyme that uses IP3 or DAG to phosphorylate target molecule

BCH4024 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions