Question

QUESTION 13 The properties of phospholipids that affect how tightly they pack together are the A number of hydrocarbon chains, the length of these chains, and the number of double bonds in these chains. B. None of these answers are correct OC number of hydrocarbon chains and the number of double bonds in these chains. D. charge of the hydrophilic head, the length of the hydrocarbon chains, and the number of double bonds in these chains. E. length of the hydrocarbon chains and the number of double bonds in these chains. F. charge of the hydrophilic head and the length of the hydrocarbon chains.

Answer 1

Ans: Phospholipids are present in the plasma membrane of the cells. The composition of the phospholipids affect the packaging of the lipids in the bilayer and also affects the fluidity.

The factors which affect the packaging are:

1. Length of the hydrocarbon chain - Hydrocarbon chain forms the tail of the phospholipids and these tails interact with each other and makes the packaging more tight. More the length of the hydrocarbon chain, more tight the packaging will be whereas shorter length will have less intermolecular interactions and hence less rigidity.

2. Number of double bonds- Double bonds cause unsaturation and more the unsaturation, the kinks of the double bond will make the phospholipids apart and the packaging will not be tight enough. The more the saturation of the hydrocarbon chain, more will be the tight packaging.

3. Number of hydrocarbon chains - more the number of hydrocarbon chains, more will be interaction between them and tightly they will be packaged.

So based on these factors, option A - number of hydrocarbon chains, the length of these two chains and the number of double bond in these chains, is the correct option.

Charge on the hydrophilic head does not affect the packaging of the phospholipids