Lecture 10

Question 1

3 prominent types of lipids in most membranes

Answer 1

• phospholipids
• gycolipids
• sterols

Question 2

The functional specialization of each membrane type is reflected in?

Answer 2

Its unique lipid composition

Question 3

Cholesterol is prominent in ___ membranes but barely detectable in _____ membranes.

Answer 3

• plasma membranes

- mitochondrial

Question 4

Cardiolipin is a major component of ____ membrane but not of the ____ membrane.

Answer 4

• inner mitochondrial membrane

- plasma membrane

Question 5

PI and its derivatives fxn to in what

Answer 5

Signal transductions triggered by hormones

Question 6

Glycolipids, which are major components of the ____ membranes of plants, are virtually absent from ___ cells.

Answer 6

• chloroplast membranes

- animal cells

Question 7

Because cardiolipin is in mitochondria and not others, what can we hypothesize?

Answer 7

Cardiolipin important to function of mitochondria

Question 8

Are sphingolipids, phosphatidylcholine, and phosphatidylethanolamine present in all membranes in the same amounts?

Answer 8

Sphingolipids, PC, and PE are present in most membranes but in varying proportions.

Question 9

What is the most abundant lipid in cell membranes

Answer 9

Phospholipids

Question 10

Are phospholipids amphipathic or not

Answer 10

Yes

Question 11

What are the possible backbones of phospholipids

Answer 11

• Sphingosine (in phosphosphingolipids) or glycerols (in phosphoglycerides)

Question 12

What is an sphingosine

Answer 12

Long-chain amino alcohol

Question 13

In phosphosphingolipids, a fatty acid is attached to the sphingosine via what kind of bond

Answer 13

Amide

Question 14

What are the 4 most common types of phosphoglycerides?

Answer 14

PC, PS, PE, and PI

Question 15

A phosphosphingolipid that is common in animal plasma membranes but absent in plant and bacteria?

Answer 15

sphingomyelin