Question

All are membrane bound cell organelles except
(A) Mitochondria
(B) Spherosomes
(C) Ribosomes
(D) Lysosomes

Answer 1

Hint: Cell organelles are present in the cytoplasm of cells. These cell organelles are metabolically active and living structures of cytoplasm. Almost all cell organelles are membranous and are distinct in terms of their structure and function.

Complete answer:
Different types of cell organelles are:
Mitochondria: It is popularly known as either the powerhouse of the cell or ATP – mill in the cell. It is also known as cells within cells. Mitochondria has a double unit membrane i.e. outer membrane and inner membrane. Both the membranes divide their lumen into two aqueous compartments known as the outer compartment and the inner compartment. These two membranes are separated by a space known as peri mitochondrial space.
Spherosomes: These cell organelles are also known as Oleosomes. They are small in size and are surrounded by a single membrane. They help in the synthesis of lipids and also functions as the storage unit of lipids.
Ribosomes: Ribosomes are composed of ribonucleic acid. These are the granular structures that take part in the synthesis of protein. One of the salient features of the ribosome is that these cell organelles are not bound by any membrane. They are also known as organelle within the organelle.
Lysosomes: During the process of packaging in the Golgi apparatus, there is the formation of many membrane-bound structures that are known as lysosomes. Lysosomes are large-sized phagocytes that are covered with a single unit membrane.

Therefore, the correct option is (C) Ribosomes.

Note:
Ribosomes are also described as the Engine of the cell. These are the smallest cell organelles which are also known as the protein factory of the cell. Ribosomes are of two types, Eukaryotic ribosomes, and prokaryotic ribosomes.