Different Types of Cell - Practice Questions & MCQ

Cellularity:

• Cellularity refers to the number of cells present in an organism. 
• Accordingly, an organism can be made up of just a single cell. 
• Such organisms are called unicellular organisms. 
• Kingdom Monera with bacteria and Kingdom Protista with organisms like algae, Paramecium, Euglena etc. contain the unicellular organisms. 
• Multicellular organisms of more than one cells. 
• The level of organization in multicellular organisms can go up to the organ system level. 

The following figure represents the cellular hierarchy in multicellular organisms:

Based on the presence or absence of well-defined nucleus, cells are of two types:

1) Prokaryotic Cells: [Gk. pro, before, and karyon, kernel, nucleus]. These are the primitive cells and are considered as evolutionary successful. These cells lack a membrane-bound nucleus as well as other membrane-bound organelles. E.g., bacteria.

2) Eukaryotic Cells: [Gk. eu, true, and karyon, kernel, nucleus]. These cells have a defined nucleus as well as membrane-bound cell organelles. E.g., Protists, Fungi, Plants, and Animals.