Question

Double membrane is absent in
A. Mitochondria
B. Chloroplast
C. Nucleus
D. Lysosomes

Answer 1

Hint:It is said that the cell membrane has a fluid mosaic structure where the proteins and phospholipids can travel around. The phospholipids can move laterally and swivel in their positions in a circular pattern, they can also move between the bilayers.

Complete answer:
First we should know about the plasma membrane to answer this question. The plasma membrane divides the cell from the world around it and governs the molecules' movement in and out of the cell. This molecule is made primarily of proteins and phospholipids. The plasma membrane is referred to as the bilayer phospholipid since the phosphate group and lipid molecules in water have distinct properties.
Now, let us find the solution from the options-
- Two membranes are surrounded by the mitochondria, known as the outer and inner membranes. The outer membrane is smoother and constitutes the mitochondria’s continuous limiting barrier, while a set of folders named the cristae shape the inner membrane. The organelle is divided into two different chambers loaded with aqueous fluid caused by the presence of two membranes. Thus option (A) is not a correct option.
- The inner membrane is comparatively less porous than the outer membrane to chemicals, and thus contains more proteins, like protein carriers. The area surrounded by the chloroplast inner membrane is known as stroma. A significant number of ordered flattened membrane sacs called thylakoids are found in Stroma. Thus option B is not the correct option.
- The nucleus is present in eukaryotic cells as a membrane-bound organelle. The nucleus, chloroplast, and mitochondria are cellular organelles that are double membrane-bound. Thus option C is not the correct option.
-Lysosomes, on the other hand, are single membrane-bound organelles containing digestive enzymes that digest waste or worn-out organelles, food debris, bacteria and macromolecules, or ingested viruses. For lysosomes, a double membrane is lacking.

Thus, the correct answer is option (D) Lysosomes.

Note:The phosphate group of the membranes becomes hydrophilic, but lipids become hydrophobic; phosphate molecules reside on the surface of the phospholipid bilayer as water is present within and outside the cell, while lipid molecules shape the inner portion of the membrane's phospholipid bilayer.