Question

Single-celled eukaryotes are included in Kingdom:
A. Protista
B. Fungi
C. Plantae
D. Monera

Answer 1

We all know that to make our study easier, all the organisms have been classified according to their characteristics into different groups. We follow the 5 Kingdom classifications to classify all the organisms. Now we know that eukaryotes are those organisms which have a well-defined nucleus.

Complete answer:
To know the correct answer to the question, we must be well aware of the eukaryotes.

Eukaryotes are those organisms which have a well-defined nucleus enclosed within a nuclear membrane. These organisms have membrane bound organelles like mitochondria, golgi apparatus and chloroplast.
All the single-celled eukaryotes are included in Kingdom Protista. The characteristics of this kingdom are:
1. They reproduce both sexually and asexually.
2. They use cilia and flagella for locomotion.
3. They have autotrophic mode as well as heterotrophic mode of nutrition.
4. Their cell can divide mitotically as well as meiotically.

Since, now we are well aware of the eukaryotes and their characteristics, hence the correct answer to the question is option A i.e. Single-celled eukaryotes are included in the Kingdom Protista.

Note: Here it must be noted that we follow Whittaker’s Five Kingdom Classification. According to this, all the organisms are classified on the basis of these features:

Complexity of the body structure
Complexity of the cell structure
Mode of nutrition
Source of nutrition
The pattern of their lifestyle(whether producers, or consumers or decomposers)