Question 1

Which of the following cell types contains cholesterol?

Accepted Answer

A)  bacteria 
B)  animal 
C)  plant 
D)  They all contain cholesterol. 
A)  bacteria 
B)  animal 
C)  plant 
D)  They all contain cholesterol.

Question 2

Transport of a compound across a cell membrane (down a concentration gradient) was measured at several concentrations. The presence or absence of ATP had no effect on the transport of this compound. Which best describes the mechanism of transport? $$\begin{array} { c c } 
\text { Concentration Difference, } & \begin{array} { c } 
\text { Transport Rate, } \
\mu \mathbf { m o l } / \mathbf { m i n }
\end{array} \
\hline \boldsymbol { M } & 30 \
2.5 & 60 \
5 & 100 \
10 & 175 \
25 & 200
\end{array}$$

Accepted Answer

A)  facilitated diffusion 
B)  passive diffusion 
C)  primary active transport 
D)  secondary active transport 
E)  proton pumping 
A)  facilitated diffusion 
B)  passive diffusion 
C)  primary active transport 
D)  secondary active transport 
E)  proton pumping

Question 3

Which of the following four fatty acids has the lowest melting point?
1)CH3CH2CH2CH2CH2COOH
2)CH3CH2CH2CH2CH2CH2CH2CH 2CH2COOH
3)CH3CH2CH2CH2CH2CH2CH2COOH
4)CH3CH=CHCH2CH2COOH

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
A)  1 
B)  2 
C)  3 
D)  4

Question 4

Which of the following is a metabolic precursor of prostaglandins & leukotrienes?

Accepted Answer

A)  vitamin A. 
B)  arachidonic acid. 
C)  sphingomyelin. 
D)  cholesterol. 
A)  vitamin A. 
B)  arachidonic acid. 
C)  sphingomyelin. 
D)  cholesterol.

Question 5

When a membrane reaches its transition temperature, integral membrane proteins dissociate from the bilayer.

Accepted Answer

A) True 
 B)False

Question 6

Which of the following best describes lipids' insolubility in water?

Accepted Answer

A)  They are typically very soluble. 
B)  They are typically insoluble. 
C)  There is no general trend as to lipids' solubility in water. 
A)  They are typically very soluble. 
B)  They are typically insoluble. 
C)  There is no general trend as to lipids' solubility in water.

Question 7

The degree of membrane fluidity depends on

Accepted Answer

A)  the percentage of lipids that contain choline 
B)  the percentage of glycolipids 
C)  the percentage of fatty acids 
D)  the percentage of unsaturated fatty acids 
A)  the percentage of lipids that contain choline 
B)  the percentage of glycolipids 
C)  the percentage of fatty acids 
D)  the percentage of unsaturated fatty acids

Question 8

In the operation of the sodium-potassium pump

Accepted Answer

A)  conformational changes in membrane proteins are inhibited 
B)  the ions involved bind to the lipid portion of the membrane 
C)  a membrane protein is phosphorylated with ATP as the source of the phosphate group 
D)  a membrane protein is phosphorylated with ADP as the source of the phosphate group 
A)  conformational changes in membrane proteins are inhibited 
B)  the ions involved bind to the lipid portion of the membrane 
C)  a membrane protein is phosphorylated with ATP as the source of the phosphate group 
D)  a membrane protein is phosphorylated with ADP as the source of the phosphate group

Question 9

Unsaturated fatty acids usually have ____ double bonds.

Accepted Answer

A)  cis 
B)  trans 
C)  no 
D)  seven or eight 
A)  cis 
B)  trans 
C)  no 
D)  seven or eight

Question 10

Sphingolipids are particularly important in these structures:

Accepted Answer

A)  Membranes 
B)  Lipoproteins 
C)  The brain and nervous system. 
D)  Membranes, the brain and the nervous system. 
E)  All of these are correct. 
A)  Membranes 
B)  Lipoproteins 
C)  The brain and nervous system. 
D)  Membranes, the brain and the nervous system. 
E)  All of these are correct.

Question 11

Which of the following is the best phrase to describe the modern view of membrane structure?

Accepted Answer

A)  Membranes are lipid-lipid bilayers. 
B)  Membranes are lipid-lipid bilayers with associated proteins. 
C)  Membranes are composed solely of lipids and proteins. 
D)  Membranes are a fluid mosaic of lipids and proteins. 
E)  Membranes are found only in eukaryotic cells. 
A)  Membranes are lipid-lipid bilayers. 
B)  Membranes are lipid-lipid bilayers with associated proteins. 
C)  Membranes are composed solely of lipids and proteins. 
D)  Membranes are a fluid mosaic of lipids and proteins. 
E)  Membranes are found only in eukaryotic cells.

Question 12

A major difficulty in extracting receptor proteins from membranes is that

Accepted Answer

A)  it is difficult to remove the proteins from the membrane without denaturation 
B)  there may be very few molecules of the protein in a cell 
C)  receptor proteins tend to have high molecular weights 
D)  all of these 
A)  it is difficult to remove the proteins from the membrane without denaturation 
B)  there may be very few molecules of the protein in a cell 
C)  receptor proteins tend to have high molecular weights 
D)  all of these

Question 13

Exhibit 8A
  
-Refer to Exhibit 8A. Which protein might help to identify the cell type?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  More than one could help identify the cell type. 
A)  1 
B)  2 
C)  3 
D)  4 
E)  More than one could help identify the cell type.

Question 14

There are likely to be huge stores of lipid vitamins in healthy animals.

Accepted Answer

A) True 
 B)False

Question 15

Which of the following would not be enriched on the outer side of the lipid bilayer compared to the inner side?

Accepted Answer

A)  Phosphoacylglyerol 
B)  Ganglioside 
C)  Cerebroside 
D)  Sphingomyelin 
A)  Phosphoacylglyerol 
B)  Ganglioside 
C)  Cerebroside 
D)  Sphingomyelin

Question 16

The distribution of lipids in membranes is

Accepted Answer

A)  uneven, with bulkier molecules on the exterior 
B)  characterized by even distribution of molecules 
C)  distinguished by the absence of cholesterol 
D)  not well understood 
A)  uneven, with bulkier molecules on the exterior 
B)  characterized by even distribution of molecules 
C)  distinguished by the absence of cholesterol 
D)  not well understood

Question 17

Which of the following is true?

Accepted Answer

A)  All fatty acids have an even number of carbons 
B)  Most fatty acids have an odd number of carbons 
C)  Fatty acids are equally likely to have an even number of carbons as they are an odd number 
D)  Fatty acids with an odd number of carbons are more rare than those with an even number 
E)  none of these 
A)  All fatty acids have an even number of carbons 
B)  Most fatty acids have an odd number of carbons 
C)  Fatty acids are equally likely to have an even number of carbons as they are an odd number 
D)  Fatty acids with an odd number of carbons are more rare than those with an even number 
E)  none of these

Question 18

Glycolipids are characterized by containing the following non-lipid component:

Accepted Answer

A)  Sugars 
B)  Glycerol 
C)  Phosphate 
D)  Sphingosine 
E)  More than one of these characterize glycolipids. 
A)  Sugars 
B)  Glycerol 
C)  Phosphate 
D)  Sphingosine 
E)  More than one of these characterize glycolipids.

Question 19

Which of the following statements concerning active transport is true?

Accepted Answer

A)  It takes place in the same direction as a concentration gradient. 
B)  It requires no expenditure of energy by the cell. 
C)  It can be compared to water running downhill. 
D)  A membrane-associate protein must be involved. 
A)  It takes place in the same direction as a concentration gradient. 
B)  It requires no expenditure of energy by the cell. 
C)  It can be compared to water running downhill. 
D)  A membrane-associate protein must be involved.

Question 20

Which of the following four fatty acids has the highest melting point?
1)CH3CH2CH2CH2CH2COOH
2)CH3CH2CH2CH2CH2CH2CH2CH 2CH2COOH
3)CH3CH2CH2CH2CH2CH2CH2COOH
4)CH3CH=CHCH2CH2COOH

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
A)  1 
B)  2 
C)  3 
D)  4

Exam 8: Lipids and Proteins Are Associated in Biological Membranes

Which of the following cell types contains cholesterol?

Which of the following four fatty acids has the lowest melting point? 1)CH3CH2CH2CH2CH2COOH 2)CH3CH2CH2CH2CH2CH2CH2CH 2CH2COOH 3)CH3CH2CH2CH2CH2CH2CH2COOH 4)CH3CH=CHCH2CH2COOH

Which of the following is a metabolic precursor of prostaglandins & leukotrienes?

When a membrane reaches its transition temperature, integral membrane proteins dissociate from the bilayer.

Which of the following best describes lipids' insolubility in water?

The degree of membrane fluidity depends on

In the operation of the sodium-potassium pump

Unsaturated fatty acids usually have ____ double bonds.

Sphingolipids are particularly important in these structures:

Which of the following is the best phrase to describe the modern view of membrane structure?

A major difficulty in extracting receptor proteins from membranes is that

Exhibit 8A -Refer to Exhibit 8A. Which protein might help to identify the cell type?

There are likely to be huge stores of lipid vitamins in healthy animals.

Which of the following would not be enriched on the outer side of the lipid bilayer compared to the inner side?

The distribution of lipids in membranes is

Which of the following is true?

Glycolipids are characterized by containing the following non-lipid component:

Which of the following statements concerning active transport is true?

Which of the following four fatty acids has the highest melting point? 1)CH3CH2CH2CH2CH2COOH 2)CH3CH2CH2CH2CH2CH2CH2CH 2CH2COOH 3)CH3CH2CH2CH2CH2CH2CH2COOH 4)CH3CH=CHCH2CH2COOH

Biochemistry and the Organization of Cells

Water: the Solvent for Biochemical Reactions

Amino Acids and Peptides

The Three-Dimensional Structure of Proteins

Protein Purification and Characterization Techniques

The Behavior of Proteins: Enzymes

The Behavior of Proteins: Enzymes, Mechanisms, and Control

Nucleic Acids: How Structure Conveys Information

Biosynthesis of Nucleic Acids: Replication

Transcription of the Genetic Code: Biosynthesis of RNA

Protein Synthesis: Translation of the Genetic Message

Nucleic Acid Biotechnology Techniques

Viruses, Cancer, and Immunology

The Importance of Energy Changes and Electron Transfer in Metabolism

Carbohydrates

Glycolysis

Storage Mechanisms and Control in Carbohydrate Metabolism

The Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Lipid Metabolism

Photosynthesis

The Metabolism of Nitrogen

Integration of Metabolism: Cellular Signaling

Filters

Which of the following four fatty acids has the lowest melting point? 1)CH₃CH₂CH₂CH₂CH₂COOH 2)CH₃CH₂CH₂CH₂CH₂CH₂CH₂CH ₂CH₂COOH 3)CH₃CH₂CH₂CH₂CH₂CH₂CH₂COOH 4)CH₃CH=CHCH₂CH₂COOH

Which of the following four fatty acids has the highest melting point? 1)CH₃CH₂CH₂CH₂CH₂COOH 2)CH₃CH₂CH₂CH₂CH₂CH₂CH₂CH ₂CH₂COOH 3)CH₃CH₂CH₂CH₂CH₂CH₂CH₂COOH 4)CH₃CH=CHCH₂CH₂COOH