Membrane Proteins and Their Functions

Q.

Which two components are plasma membrane made up of?

Q.

What are the phospholipid layers of cell membrane?

Q.

Comment on the statement “plasma membrane is made up of two components.”

Q. Channels in the plasma membrane through which molecules enter or leave the cell

1. Phospholipid polar heads
2. Membrane proteins
3. Phospholipid tails
4. All of the above

Q.

The presence of a cell wall enables bacteria to live in a hypotonic medium without bursting.

1. True
2. False

Q. Which one of the following is correct for the trans-membrane proteins in lipid bilayer of plasma membrane ?

Q. In fluid mosaic model of plasma membrane:

1. Upper layer is non-polar and hydrophilic
2. Polar layer is hydrophobic
3. Phospholipids form a bimolecular layer in which proteins are embedded
4. Proteins from a middle layer

Q. Assertion :A cell membrane shows fluid-mosaic behaviour. Reason: A membrane is composite of lipids and proteins.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Assertion is incorrect but Reason is correct

Q. Choose the correct answer from the alternatives given.
The following theory best explains the structure of the plasma membrane

1. Sandwich theory
2. Fluid-mosaic theory
3. Unit membrane theory
4. Electrochemical theory

Q. Membrane phospholipids are

1. Amphipathic
2. None of the above
3. Amphibolic
4. Hydrophobic

Q.

Why are cells generally of small size?

Q. Phospholipid bilayer is not found in the membrane of ______________.

1. Sphaerosome
2. Peroxisome
3. Lysosome
4. Glyoxysome

Q. Structural lipids of cell membrane are

1. Simple lipid
2. Chromolipid
3. Phospholipid
4. Steroid

Q. In 2003, the chemistry Nobel Prize was awarded for which of the following work?

1. Aquaporins
2. Ca${}^{++}$
3. Na${}^{++}$ channels
4. Methyl chavicol

Q. Select the correct experimental observation, that supports the fluid mosaic model of membrane structure.

1. The capping of fluorescent antibodies specific for cell-surface receptors
2. The measurement of ions flowing through ion-gated channel proteins by patch clamps
3. The pseudopodial movement of amoeba
4. The presence of the cytoskeleton underneath the surface of the membrane
5. The scaffolding and kinetic proteins associated with the movement of cilia

Q. Assertion :Lipids present in the outer and inner side of plasma membrane are same. Reason: Oligosaccharides are attached to external surface as well as inner surface of a biomembrane.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
3. Assertion is correct but Reason is incorrect.
4. Both Assertion and Reason are incorrect.

Q. Channels in the plasma membrane through which molecules enter or leave the cell

1. Membrane proteins
2. Phospholipid tails
3. Phospholipid polar heads
4. All of the above

Q. Which is not a constituent of cell membrane?

Q. A phospholipid molecule has a head and two tails, The tails are found

1. At the surfaces of the membrane
2. In the interior of the membrane
3. Spanning the membrane
4. Both (a) and (b)

Q. The phospholipid bilayer

1. Is readily permeable to large, polar molecules
2. Is entirely hydrophobic
3. Has different lipids in the two layers
4. Is entirely hydrophilic

Q. Read the assertion and reason carefully to mark the correct option in question


Assertion: A cell membrane shows quasi-fluid behaviour.

Reason: A membrane is a mosaic or composite of diverse lipids and proteins.

1. If both assertion and reason are true and the reason is the correct explanation of the assertion.
2. If both assertion and reason are false.
3. If assertion is true but reason is false.
4. If both assertion and reason are true but the reason is not the correct explanation of the assertion.

Q. Membrane proteins are found in

1. Cell wall
2. Extracellular matrix
3. Cell membrane
4. All of the above

Q.

Fluid Mosaic Model states that membranes are composed of a Phospholipid Bilayer with various ___ floating around within it.

Q. Membrane proteins are found in

1. Extracellular matrix
2. Cell wall
3. Cell membrane
4. All of the above

Q.

Fluid Mosaic Model states that membranes are composed of a Phospholipid Bilayer with various ___ floating around within it.

Q. Label the parts of the plasma membrane.

1. $Hydrophillicregion$
2. Integral protein
3. Membrane channel
4. $Hydrophobicregion$

Q. Which of the following is dominant intracellular ion?

1. Potassium
2. Chloride
3. Calcium
4. Phosphate

Q. Read the assertion and reason carefully to mark the correct option in question


Assertion: A cell membrane shows quasi-fluid behaviour.

Reason: A membrane is a mosaic or composite of diverse lipids and proteins.

1. If assertion is true but reason is false.
2. If both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. If both assertion and reason are false.
4. If both assertion and reason are true and the reason is the correct explanation of the assertion.

Q. Label the parts of the plasma membrane.

1. $Hydrophillicregion$
2. Integral protein
3. Membrane channel
4. $Hydrophobicregion$