Help with Questions on Membrane Structure, Proteins & Vitamin E

[littlelady]

I have some questions that i am not sure...can u guys help me out ?

1. Which of the following is the best phrase to describe the modern view of membrane
structure?
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 eucaryotic cells.

2. Proteins in biological membranes participate in all of the following activities, except:
a. Transport
b. Catalytic activity
c. Blood clotting
d. Receptor sites
e. All of these are correct.

3. Transport across a membrane can involve all the following, except:
a. Passive transport
b. Facilitated transport or diffusion.
c. Protein channels
d. Passive transport, facilitated transport or diffusion.
e. All of these are correct.

4. The mechanism of membrane transport may involve the following:
a. ATP hydrolysis.
b. Conformation change of membrane proteins.
c. Phosphorylation or dephosphorylation of membrane proteins.
d. ATP hydrolysis and conformation change of membrane proteins.
e. All of these are correct.

5. Vitamin E has all of the following properties, except:
a. It is an antioxidant.
b. It can be made in the sunshine.
c. It is essential for at least some mammal's fertility.
d. It is often a component of membranes.
e. All of these describe vitamin E.


6. A bacterial cell wall is composed of:
a. One type of polysaccharide and 2 different types of oligopeptides, which are
cross-linked.
b. One type of polysaccharide and 1 type of oligopeptide, arranged in 2 different directions.
c. One type of polysaccharide and an oligopeptide covalently bonded to the cell membrane.
d. Two different polysaccharides and 1 type of oligopeptide, which are cross-linked.
e. More than one of these statements is true.

 

[ace123]

Well do you have ideas about any of them. Otherwise I'm just giving you answers...

 

[jim mcnamara]

Another way we can help is to get you to understand how to find your own answers in your textbook.

The index for a book is in the back - so try looking under the section on "membrane" or "membranes": under that topic there will be subtopics, probably "structure" is one of them. Turn to the page listed there - probably has a nice picture that answers Q1.