Question

Question: In what way do the membranes of a eukaryotic cell vary?

1. Phospholipids are found only in certain membranes.
2. Certain proteins are unique to each membrane.
3. Only certain membranes of the cell are selectively permeable.

4. Only certain membranes are constructed from amphipathic molecules.

Short answer

1. The statement “Phospholipids are found only in certain membranes.” is false.
2. The statement “Certain proteins are unique to each membrane” is true.
3. The statement “Only certain membranes of the cell are selectively permeable” is false.
4. The statement “Only certain membranes are constructed from amphipathic molecules” is false.

Step-by-step solution

Cell membrane

The cell membrane is the unique feature in eukaryotic cells that aids transport materials within and across the cells. This transport process is an important event for all metabolic activities.

Explanation of option ‘(A)’

The cell membrane has phospholipids in its structure. The structure of the phospholipids is composed of hydrophilic and hydrophobic ends. The glycerol structure attaches the hydrophilic and hydrophobic ends.

The phospholipids are commonly present in all elements. It is not limited to a particular type of cell membrane.

Therefore, the given statement is false.

Explanation of option ‘(B)’

Proteins are present in the cell membrane are known as membrane proteins. These proteins found in the membrane are integral membrane proteins, peripheral proteins, and lipids anchored proteins.

Integral membranes are submerged in the membrane. Peripheral proteins are proteins that are temporarily attached to the membrane. Lipids anchored are the proteins present with the lipid attachment.

So, proteins are unique to each type of cell membrane.

Therefore, the given statement is true.

Explanation of option ‘(C)’

Selectively permeable property is the common property of the cell membrane. It is an important feature of the membrane because the cell membrane has to select the ions and molecules that pass through the membrane. The cell membrane cannot be freely permeable or non-permeable.

If the cell membrane is not permeable, then there is no transportation process. If the cell membrane is freely permeable, cells will experience breakage due to the accumulation of materials.

Hence, all cell membrane has to be strictly selectively permeable.

Therefore, the given statement is false.

Explanation of option ‘(D)’

All cell membranes are made of amphipathic molecules. The components of the cell membrane have both hydrophilic and hydrophobic ends. The hydrophilic ends face the cell membrane, and the hydrophobic ends face inside the cell membrane.

All membrane has to be amphipathic molecules. It is not the property of a particular molecule.

Therefore, the given statement is false.