What is a Cell?
Every living thing — from a bacterium drifting in pond water to a muscle fibre in your arm — is built from the same fundamental unit: the cell. This quiz tests Lesson 1 of Cell: The Unit of Life, covering:
- Living versus non-living things and the basic unit of life
- Unicellular and multicellular organisms
- Independent existence and the essential functions of life
- The cell as the fundamental structural and functional unit
- Antonie von Leeuwenhoek, Robert Brown and the nucleus
- The microscope and the electron microscope
Answer all 15 questions and check each explanation to strengthen your understanding before moving on to cell theory.
Q1. What is the basic unit of life present in all living organisms?
The lesson states that the answer to what makes an organism living is the presence of the basic unit of life — the cell — in all living organisms.
Q2. Organisms composed of a single cell are called:
The source text says some organisms are composed of a single cell and are called unicellular organisms.
Q3. Organisms like us, composed of many cells, are called:
The lesson states that organisms composed of many cells, like us, are called multicellular organisms.
Q4. Which two capabilities are attributed to unicellular organisms?
Unicellular organisms are capable of (i) independent existence and (ii) performing the essential functions of life.
Q5. According to the lesson, anything less than a complete structure of a cell:
The text states clearly that anything less than a complete structure of a cell does not ensure independent living.
Q6. Why is the cell called the fundamental structural and functional unit of all living organisms?
The cell is structural because bodies are built from it and functional because the essential processes of life happen within it.
Q7. Who first saw and described a live cell?
The lesson states that Antonie Von Leeuwenhoek first saw and described a live cell.
Q8. Robert Brown is credited in the lesson with the discovery of the:
According to the source text, Robert Brown later discovered the nucleus.
Q9. Which instrument made the earliest observations of cells possible?
The lesson notes that the invention of the microscope and its improvement made observations of cells possible.
Q10. Which instrument revealed all the structural details of the cell?
The text says the improvement of the microscope leading to the electron microscope revealed all the structural details of the cell.
Q11. What is the answer given in the lesson to the question of what an inanimate thing lacks that a living thing has?
The lesson answers this question with the presence of the basic unit of life — the cell — in all living organisms.
Q12. Which statement best describes the relationship between diversity of forms and cellular organisation?
The lesson explains that it is the cellular organisation of all life forms that emphasises the unity underlying the variety of forms.
Q13. A bacterium living on its own in pond water is best described as:
A single-celled organism such as a bacterium is unicellular and is capable of independent existence and essential life functions.
Q14. Which sequence correctly matches the observations described in the lesson?
The lesson states that Antonie Von Leeuwenhoek first saw and described a live cell, and Robert Brown later discovered the nucleus.
Q15. Which of the following is NOT a reason given in the lesson for calling the cell the fundamental unit of life?
The lesson never claims cells are always visible to the naked eye; in fact the microscope was needed to observe them. The other options are all given in the text.