Question 1

What property is used to determine the probability that a segment of a protein will be found embedded in a membrane?

Accepted Answer

A)  hydropathy 
B)  polarity 
C)  acidity 
D)  entropy 
E)  solvation 
A)  hydropathy 
B)  polarity 
C)  acidity 
D)  entropy 
E)  solvation A

Question 2

What is the function of prostaglandin H2 synthase-1? How does its position in the membrane facilitate its activity?

Accepted Answer

Prostaglandin H₂ synthase-1 converts arachidonic acid into prostaglandin H₂.The protein is embedded in the membrane,with a hydrophobic channel submerged about halfway through the bilayer.The arachidonic acid is a product of membrane lipid hydrolysis and enters the protein channel from within the membrane,successfully avoiding any interaction with aqueous environments.

Question 3

________________ is a membrane lipid composed of sphingosine,fatty acid,and a simple sugar like glucose or galactose.

Accepted Answer

Cerebroside

Question 4

Which of the following statements is consistent with the structure of biological membranes?

Accepted Answer

A)  All membrane proteins are integral and associate with the hydrophobic region of the membrane. 
B)  Both proteins and lipids readily undergo transverse ("flip-flop") diffusion from the inside to the outside of the membrane. 
C)  Membranes are symmetric. 
D)  The membrane lipids self-assemble to form the lipid bilayer. 
E)  A biological membrane consists of proteins sandwiched between two layers of lipids, which are referred to as a lipid bilayer. 
A)  All membrane proteins are integral and associate with the hydrophobic region of the membrane. 
B)  Both proteins and lipids readily undergo transverse ("flip-flop") diffusion from the inside to the outside of the membrane. 
C)  Membranes are symmetric. 
D)  The membrane lipids self-assemble to form the lipid bilayer. 
E)  A biological membrane consists of proteins sandwiched between two layers of lipids, which are referred to as a lipid bilayer.

Question 5

In phosphoglycerides,the fatty acids are linked to the glycerol backbone by ______________ linkages.

Accepted Answer

The answer of In phosphoglycerides,the fatty acids are linked to...

Question 6

___________________ membrane proteins are bound to membranes primarily by electrostatic and hydrogen bond interactions with the head groups of lipids.

Accepted Answer

The answer of ___________________ membrane proteins are bound to membranes...

Question 7

What protein polymerizes into a lattice network around a budding membrane?

Accepted Answer

A)  porin 
B)  clathrin 
C)  epsin 
D)  G protein 
E)  glycophorin 
A)  porin 
B)  clathrin 
C)  epsin 
D)  G protein 
E)  glycophorin

Question 8

Draw a cross-section of a micelle and a membrane bilayer.

Accepted Answer

Micelles are spherical arrangements in w

Question 9

How many molecules thick are membranes?

Accepted Answer

A)  one 
B)  two 
C)  infinite 
D)  varying thickness, depending on structure 
E)  None of the answers is correct. 
A)  one 
B)  two 
C)  infinite 
D)  varying thickness, depending on structure 
E)  None of the answers is correct.

Question 10

__________________ contain a double bond three carbons from the distal end of the fatty acid.

Accepted Answer

The answer of __________________ contain a double bond three carbons...

Question 11

Ionized fatty acids readily form ______________ in aqueous solutions.

Accepted Answer

The answer of Ionized fatty acids readily form ______________ in...

Question 12

Which of the following is NOT correct concerning the structure given?

Accepted Answer

A)  It is a component of biological membranes. 
B)  It is amphipathic. 
C)  It is a sphingolipid. 
D)  It is a phosphoglyceride. 
E)  It is phosphatidyl choline. 
A)  It is a component of biological membranes. 
B)  It is amphipathic. 
C)  It is a sphingolipid. 
D)  It is a phosphoglyceride. 
E)  It is phosphatidyl choline.

Question 13

What complex is observed between cholesterol and membrane phospholipids?

Accepted Answer

A)  salt bridge 
B)  clathrate 
C)  lipid raft 
D)  phospholipid domain 
E)  None of the answers is correct. 
A)  salt bridge 
B)  clathrate 
C)  lipid raft 
D)  phospholipid domain 
E)  None of the answers is correct.

Question 14

Why do most phospholipids preferentially form sheets instead of micelles?

Accepted Answer

The two tails of pho

Question 15

Which of the following membrane-bound organelles is thought to have evolved from bacteria by endosymbosis?

Accepted Answer

A)  peroxisomes 
B)  mitochondria 
C)  cell walls 
D)  nuclei 
E)  endoplasmic reticulum 
A)  peroxisomes 
B)  mitochondria 
C)  cell walls 
D)  nuclei 
E)  endoplasmic reticulum

Question 16

What is the most common process by which lipids and proteins move in the membrane bilayer?

Accepted Answer

A)  kinesin-mediated movement 
B)  flip-flopping 
C)  translocation 
D)  lateral diffusion 
E)  asymmetric longitudinal flipping 
A)  kinesin-mediated movement 
B)  flip-flopping 
C)  translocation 
D)  lateral diffusion 
E)  asymmetric longitudinal flipping

Question 17

What is the number of carbons found in the most commonly observed fatty acids?

Accepted Answer

A)  12 or 14 
B)  14 or 16 
C)  16 or 18 
D)  18 or 20 
E)  20 or 22 
A)  12 or 14 
B)  14 or 16 
C)  16 or 18 
D)  18 or 20 
E)  20 or 22

Question 18

Explain the relationship between the endoplasmic reticulum and the nuclear membrane and one additional characteristic about the nuclear membrane that sets it apart from other membranes.

Accepted Answer

The nuclear membrane and endop

Question 19

The low incidence of protein or lipid flip-flop in a membrane preserves

Accepted Answer

A)  membrane fluidity. 
B)  membrane melting temperatures. 
C)  membrane asymmetry. 
D)  membrane fluidity and membrane melting temperatures. 
E)  All of the answers are correct. 
A)  membrane fluidity. 
B)  membrane melting temperatures. 
C)  membrane asymmetry. 
D)  membrane fluidity and membrane melting temperatures. 
E)  All of the answers are correct.

Question 20

Which of the following is true?

Accepted Answer

A)  Membranes are lipid bilayers. 
B)  Membrane lipids have both hydrophobic and hydrophilic properties. 
C)  Many membranes are electrically polarized. 
D)  All of the answers are correct. 
E)  A and B. 
A)  Membranes are lipid bilayers. 
B)  Membrane lipids have both hydrophobic and hydrophilic properties. 
C)  Many membranes are electrically polarized. 
D)  All of the answers are correct. 
E)  A and B.

Exam 12: Lipids and Cell Membranes

What property is used to determine the probability that a segment of a protein will be found embedded in a membrane?

What is the function of prostaglandin H2 synthase-1? How does its position in the membrane facilitate its activity?

________________ is a membrane lipid composed of sphingosine,fatty acid,and a simple sugar like glucose or galactose.

Which of the following statements is consistent with the structure of biological membranes?

In phosphoglycerides,the fatty acids are linked to the glycerol backbone by ______________ linkages.

___________________ membrane proteins are bound to membranes primarily by electrostatic and hydrogen bond interactions with the head groups of lipids.

What protein polymerizes into a lattice network around a budding membrane?

Draw a cross-section of a micelle and a membrane bilayer.

How many molecules thick are membranes?

__________________ contain a double bond three carbons from the distal end of the fatty acid.

Ionized fatty acids readily form ______________ in aqueous solutions.

Which of the following is NOT correct concerning the structure given?

What complex is observed between cholesterol and membrane phospholipids?

Why do most phospholipids preferentially form sheets instead of micelles?

Which of the following membrane-bound organelles is thought to have evolved from bacteria by endosymbosis?

What is the most common process by which lipids and proteins move in the membrane bilayer?

What is the number of carbons found in the most commonly observed fatty acids?

Explain the relationship between the endoplasmic reticulum and the nuclear membrane and one additional characteristic about the nuclear membrane that sets it apart from other membranes.

The low incidence of protein or lipid flip-flop in a membrane preserves

Which of the following is true?

Biochemistry: An Evolving Science

Protein Composition and Structure

Exploring Proteins and Proteomes

DNA, RNA, and the Flow of Genetic Information

Exploring Genes and Genomes

Exploring Evolution and Bioinformatics

Hemoglobin: a Portrait of a Protein in Action

Enzymes: Basic Concepts and Kinetics

Catalytic Strategies

Regulatory Strategies

Carbohydrates

Membrane Channels and Pumps

Signal-Transduction Pathways

Metabolism: Basic Concepts and Design

Glycolysis and Gluconeogenesis

The Citric Acid Cycle

Oxidative Phosphorylation

The Light Reactions of Photosynthesis

The Calvin Cycle and the Pentose Phosphate Pathway

Glycogen Metabolism

Fatty Acid Metabolism

Protein Turnover and Amino Acid Catabolism

The Biosynthesis of Amino Acids

Nucleotide Biosynthesis

Biosynthesis of Membrane Lipids and Steroids

The Integration of Metabolism

DNA Replication, repair, and Recombination

RNA Synthesis and Processing

Protein Synthesis

The Control of Gene Expression in Prokaryotes

The Control of Gene Expression in Eukaryotes

Sensory Systems

The Immune System

Molecular Motors

Drug Development

Filters

What is the function of prostaglandin H₂ synthase-1? How does its position in the membrane facilitate its activity?