Question 1

Cholesterol reduces membrane permeability to small ___ and increases membrane ___ .

Accepted Answer

solutes, stability

Question 2

The alteration of a protein's ___ microenvironment may be facilitated by its association with lipid rafts.

Accepted Answer

lipid

Question 3

Peripheral membrane proteins are loosely attached to the membrane by interaction with an ___ membrane protein.

Accepted Answer

integral

Question 4

The response for question 5 in membrane physiology is ___ .

Accepted Answer

A

Question 5

In aqueous solution, the most stable configuration of phospholipids can form a ___ with polar head groups on the outside.

Accepted Answer

bilayer

Question 6

The proportion of ___ relative to phospholipids in the membrane is significant.

Accepted Answer

sphingolipids

Question 7

Glycerophospholipids have a glycerol molecule with two long-chain fatty acids esterified to carbons ___ and ___.

Accepted Answer

1, 2

Question 8

Double bonds in acyl chains ___ fluidity.

Accepted Answer

increase

Question 9

The two most common phosphoglycerides in cell membranes are phosphatidylethanolamine (PE) and ___ (PC).

Accepted Answer

phosphatidylcholine

Question 10

GPI-anchored proteins and various signal transduction receptors appear to be enriched in ___ rafts.

Accepted Answer

lipid

Question 11

The length and ___ of fatty acid chains in phospholipids affect membrane composition.

Accepted Answer

saturation

Question 12

The acyl tails of lipids typically range from ___ to ___ carbons long.

Accepted Answer

14, 20

Question 13

A special type of interaction that attaches a peripheral membrane protein to the membrane is via a lipid that is ___ linked to the protein.

Accepted Answer

covalently

Question 14

Lipid bilayers can exhibit ___, allowing individual lipids to move about in the membrane.

Accepted Answer

fluidity

Question 15

The surface density of integral ___ is crucial for membrane structure.

Accepted Answer

membrane proteins

Question 16

Above the critical temperature, the acyl side chains become more ___ and ___.

Accepted Answer

fluid, disordered

Question 17

Longer acyl chains are ___ fluid.

Accepted Answer

less

Question 18

Caveolae have been implicated in ___, such as the LDL receptor.

Accepted Answer

endocytosis

Question 19

Phosphatidylinositol (PI) is important as it is the source of second messengers such as inositol tris phosphate (IP3) and ___ (DAG).

Accepted Answer

diacylglycerol

Question 20

Sphingomyelin is derived from the amino alcohol ___.

Accepted Answer

sphingosine

Question 21

Gangliosides are a class of glycosphingolipids that have an oligosaccharide group with one or more ___ acid residues attached.

Accepted Answer

N-acetylneuraminic

Question 22

Rafts may have longer acyl chains than the bulk membrane, producing an increase in membrane ___ in the region of the rafts.

Accepted Answer

thickness

Question 23

For question 2 regarding membrane composition, the answer is ___ .

Accepted Answer

A

Question 24

Carbohydrates are covalently bound to membrane proteins to produce ___ or to lipids to produce ___.

Accepted Answer

glycoproteins, glycolipids

Question 25

The plasma membrane of an animal cell is primarily composed of phospholipids, sphingolipids, ___, and protein, with some carbohydrate.

Accepted Answer

cholesterol

Question 26

Most acyl tails in lipids are ___ or ___ carbons long.

Accepted Answer

16, 18

Question 27

The acyl tails can be either straight or ___ depending on the fatty acids.

Accepted Answer

kinked

Question 28

A pure lipid bilayer is impermeable to ___ molecules.

Accepted Answer

polar

Question 29

Specific lipids and proteins are found in subdomains within cell membranes, commonly referred to as ___ rafts.

Accepted Answer

lipid

Question 30

Similar mechanisms have been proposed for b-amyloid entry associated with ___ Disease.

Accepted Answer

Alzheimer’s

Question 31

Cholesterol, a steroid alcohol, alters the ___ of the cell membrane.

Accepted Answer

fluidity

Question 32

Membrane fluidity ___ as the % of unsaturated fatty acids increases.

Accepted Answer

increases

Question 33

The number of metabolically active ___ influences the cytoplasmic concentration of ATP.

Accepted Answer

mitochondria

Question 34

Phospholipid molecules are described as ___ because they have both polar and nonpolar parts.

Accepted Answer

amphipathic

Question 35

The major components of membranes are ___ and ___.

Accepted Answer

lipids, proteins

Question 36

The acyl tails of phospholipids prefer a ___ environment.

Accepted Answer

nonpolar

Question 37

Lipid rafts are small, ranging from ___ to ___ nm.

Accepted Answer

10, 200

Question 38

Cholesterol decreases membrane fluidity at ___ temperatures but increases it at ___ temperatures.

Accepted Answer

high, low

Question 39

Some membrane proteins are associated with ___ rafts, while others may be excluded from them.

Accepted Answer

lipid

Question 40

In membrane composition and structure, the correct answer for question 1 is ___ .

Accepted Answer

B

Question 41

The lipid composition of cell membranes varies from membrane to membrane in terms of the class of ___ and the breakdown of individual ___.

Accepted Answer

lipids, phospholipids

Question 42

The net charge of phosphoglycerides depends on the ___ group, which affects the nature of the membrane surface.

Accepted Answer

head

Question 43

Integral membrane proteins cross the entire membrane either once or ___ times.

Accepted Answer

multiple

Question 44

Phosphatidylserine (PS) has a net charge of ___ due to its headgroup.

Accepted Answer

-1

Question 45

A type of lipid anchor that involves phosphatidylinositol attached to a glycan is called ___ anchor.

Accepted Answer

glycosylphosphatidylinositol (GPI)

Question 46

GPI anchors help control the ___ of a specific protein on the membrane.

Accepted Answer

localization

Question 47

Peripheral membrane proteins can often be released from the membrane without disruption by altering the ___ or ionic strength.

Accepted Answer

pH

Question 48

Cholesterol concentration and temperature are two factors that determine the ___ of membranes.

Accepted Answer

fluidity

Question 49

Acyl tails can either be saturated with ___ double bonds or unsaturated with ___ or more double bonds.

Accepted Answer

no, one

Question 50

Phospholipids are phosphorylated lipids derived from ___ or ___.

Accepted Answer

glycerol, sphingosine

Question 51

The most abundant lipids in the cell membrane are ___ (aka phosphoglycerides).

Accepted Answer

glycerophospholipids

Question 52

Below the melting temperature, the acyl chains transition to a ___-like state.

Accepted Answer

gel

Question 53

A special type of lipid raft known as a ___ (plural: caveolae) consists of small invaginations in the plasma membrane.

Accepted Answer

caveola

Question 54

The presence of caveolins in caveolae leads to their ___.

Accepted Answer

invagination

Question 55

At body temperatures, cholesterol ___ fluidity.

Accepted Answer

decreases

Question 56

Differences in lipid composition between the intracellular and extracellular leaflets of the membrane are established during ___ and maintained by specific lipid transporter proteins.

Accepted Answer

membrane biogenesis

Question 57

The prion protein is a ___-anchored protein that preferentially exists in lipid rafts.

Accepted Answer

GPI

Question 58

Internalization of the prion protein from lipid rafts by macropinocytosis is thought to be an initial step in the disease process of ___ disease.

Accepted Answer

Creutzfeldt-Jakob

Question 59

Small lipid-permeable molecules such as ___ can cross a pure lipid bilayer.

Accepted Answer

steroid hormones

Question 60

The basic model of a biological membrane is called the ___ model.

Accepted Answer

fluid mosaic

Question 61

In the fluid mosaic model, proteins can move ___ within the plane of the membrane.

Accepted Answer

laterally

Question 62

Biological membranes have distinct __ and ___ composition.

Accepted Answer

lipid, protein

Question 63

The enrichment of particular proteins in a lipid raft facilitates their activity by providing ___ proximity to other proteins.

Accepted Answer

spatial

Question 64

Membrane proteins play roles in ___ transport, signal transduction, enzymatic activity, and cell-cell recognition.

Accepted Answer

solute

Cholesterol reduces membrane permeability to small ___ and increases membrane ___ .

The alteration of a protein's ___ microenvironment may be facilitated by its association with lipid rafts.

Peripheral membrane proteins are loosely attached to the membrane by interaction with an ___ membrane protein.

The response for question 5 in membrane physiology is ___ .

In aqueous solution, the most stable configuration of phospholipids can form a ___ with polar head groups on the outside.

The proportion of ___ relative to phospholipids in the membrane is significant.

Glycerophospholipids have a glycerol molecule with two long-chain fatty acids esterified to carbons ___ and ___.

Double bonds in acyl chains ___ fluidity.

The two most common phosphoglycerides in cell membranes are phosphatidylethanolamine (PE) and ___ (PC).

GPI-anchored proteins and various signal transduction receptors appear to be enriched in ___ rafts.

The length and ___ of fatty acid chains in phospholipids affect membrane composition.

The acyl tails of lipids typically range from ___ to ___ carbons long.

A special type of interaction that attaches a peripheral membrane protein to the membrane is via a lipid that is ___ linked to the protein.

Lipid bilayers can exhibit ___, allowing individual lipids to move about in the membrane.

The surface density of integral ___ is crucial for membrane structure.

Above the critical temperature, the acyl side chains become more ___ and ___.

Longer acyl chains are ___ fluid.

Caveolae have been implicated in ___, such as the LDL receptor.

Phosphatidylinositol (PI) is important as it is the source of second messengers such as inositol tris phosphate (IP3) and ___ (DAG).

Sphingomyelin is derived from the amino alcohol ___.

Gangliosides are a class of glycosphingolipids that have an oligosaccharide group with one or more ___ acid residues attached.

Rafts may have longer acyl chains than the bulk membrane, producing an increase in membrane ___ in the region of the rafts.

For question 2 regarding membrane composition, the answer is ___ .

Carbohydrates are covalently bound to membrane proteins to produce ___ or to lipids to produce ___.

The plasma membrane of an animal cell is primarily composed of phospholipids, sphingolipids, ___, and protein, with some carbohydrate.

Most acyl tails in lipids are ___ or ___ carbons long.

The acyl tails can be either straight or ___ depending on the fatty acids.

A pure lipid bilayer is impermeable to ___ molecules.

Specific lipids and proteins are found in subdomains within cell membranes, commonly referred to as ___ rafts.

Similar mechanisms have been proposed for b-amyloid entry associated with ___ Disease.

Cholesterol, a steroid alcohol, alters the ___ of the cell membrane.

Membrane fluidity ___ as the % of unsaturated fatty acids increases.

The number of metabolically active ___ influences the cytoplasmic concentration of ATP.

Phospholipid molecules are described as ___ because they have both polar and nonpolar parts.

The major components of membranes are ___ and ___.

The acyl tails of phospholipids prefer a ___ environment.

Lipid rafts are small, ranging from ___ to ___ nm.

Cholesterol decreases membrane fluidity at ___ temperatures but increases it at ___ temperatures.

Some membrane proteins are associated with ___ rafts, while others may be excluded from them.

In membrane composition and structure, the correct answer for question 1 is ___ .

The lipid composition of cell membranes varies from membrane to membrane in terms of the class of ___ and the breakdown of individual ___.

The net charge of phosphoglycerides depends on the ___ group, which affects the nature of the membrane surface.

Integral membrane proteins cross the entire membrane either once or ___ times.

Phosphatidylserine (PS) has a net charge of ___ due to its headgroup.

A type of lipid anchor that involves phosphatidylinositol attached to a glycan is called ___ anchor.

GPI anchors help control the ___ of a specific protein on the membrane.

Peripheral membrane proteins can often be released from the membrane without disruption by altering the ___ or ionic strength.

Cholesterol concentration and temperature are two factors that determine the ___ of membranes.

Acyl tails can either be saturated with ___ double bonds or unsaturated with ___ or more double bonds.

Phospholipids are phosphorylated lipids derived from ___ or ___.

The most abundant lipids in the cell membrane are ___ (aka phosphoglycerides).

Below the melting temperature, the acyl chains transition to a ___-like state.

A special type of lipid raft known as a ___ (plural: caveolae) consists of small invaginations in the plasma membrane.

The presence of caveolins in caveolae leads to their ___.

At body temperatures, cholesterol ___ fluidity.

Differences in lipid composition between the intracellular and extracellular leaflets of the membrane are established during ___ and maintained by specific lipid transporter proteins.

The prion protein is a ___-anchored protein that preferentially exists in lipid rafts.

Internalization of the prion protein from lipid rafts by macropinocytosis is thought to be an initial step in the disease process of ___ disease.

Small lipid-permeable molecules such as ___ can cross a pure lipid bilayer.

The basic model of a biological membrane is called the ___ model.

In the fluid mosaic model, proteins can move ___ within the plane of the membrane.

Biological membranes have distinct __ and ___ composition.

The enrichment of particular proteins in a lipid raft facilitates their activity by providing ___ proximity to other proteins.

Membrane proteins play roles in ___ transport, signal transduction, enzymatic activity, and cell-cell recognition.

The answer to question 3 in the context of membrane structure is ___ .

In the answers provided, question 4 corresponds to ___ .

Most proteins of biological membranes are associated with either the ___ surface or the ___ surface of the bilayer.

The ___ of the extracellular environment can impact membrane function.

Major lipid components include glycerophospholipids, sphingolipids, and ___.

The phosphate in glycerophospholipids can either be the free acid or an ester with one of several ___.

Caveolins are ___-modified membrane proteins that bind cholesterol.

A saturated fatty acid is usually on C1, while an unsaturated fatty acid is attached to ___.

Cell membranes exhibit lateral ___ in membrane composition.

Lipid rafts are enriched in ___ and sphingolipids relative to the rest of the membrane.

Lipid rafts can move about in the membrane and ___ with one another to form a larger raft.

Cholesterol reduces membrane permeability to small _ and increases membrane _ .

Glycerophospholipids have a glycerol molecule with two long-chain fatty acids esterified to carbons _ and _.

The acyl tails of lipids typically range from _ to _ carbons long.

Above the critical temperature, the acyl side chains become more _ and _.

Carbohydrates are covalently bound to membrane proteins to produce _ or to lipids to produce _.

Most acyl tails in lipids are _ or _ carbons long.

The major components of membranes are _ and _.

Lipid rafts are small, ranging from _ to _ nm.

Cholesterol decreases membrane fluidity at _ temperatures but increases it at _ temperatures.

The lipid composition of cell membranes varies from membrane to membrane in terms of the class of _ and the breakdown of individual _.

Acyl tails can either be saturated with _ double bonds or unsaturated with _ or more double bonds.

Phospholipids are phosphorylated lipids derived from _ or _.

Biological membranes have distinct and _ composition.

Most proteins of biological membranes are associated with either the _ surface or the _ surface of the bilayer.