Questions And Answers On Fundamentals of Cell Biology

Question: What are the building blocks of life?

Answer: Cell

Explanation: Cells are the most basic, functional and the smallest unit that make up living Organisms. Thus, they are called the Building Blocks of Life. A single cell performs tasks like respiration, eliminating waste, producing energy and also reproduction.

Question: Who discovered the Cell?

Answer: Robert Hooke

Explanation: In 1665, Robert Hooke observed a thin slice of bottle cork under a primitive compound microscope. He saw that it had compartments just like the Honeycomb. He called the compartments 'Cell', which means a 'small room' in Latin.

Question: What is the study of cells called?

Answer: Cell Biology

Explanation: Robert Hooke's discovery of Cells in 1665 led to a whole new line of scientific studies. Cell Biology, which was once called Cytology is the study of various structures and functions of the cell.

Question: What are unicellular organisms?

Answer: They are organisms with a single cell

Explanation: Unicellular organisms are single-celled organisms, which means they are made up of only one cell. Multi-cellular organisms on the other hand are made up of many cells.

Question: Which organisms are the most primitive forms of life?

Answer: Prokaryotes

Explanation: Prokaryotes are single-celled organisms (unicellular) that were the first ever life forms on Earth.

Question: Are all unicellular organisms prokaryotes?

Answer: No

Explanation: Unicellular organisms are divided into Prokaryotes and Eukaryotes.
Bacteria is an example of unicellular Prokaryote. Protozoans like Amoeba are an example of unicellular Eukaryotes.

Question: What are Prokaryotes?

Answer: Unicellular organisms with no nucleus or membrane-bound organelles

Explanation: The word Prokaryote comes from a Greek word: Pro (before) and Karyon (Nucleus). They do not have a nucleus or other membrane-bound organelles (Subunits of cell that carry out specific function). Eukaryotes, on the other hand, have a well-defined Nucleus and membrane-bound organelles.

Question: Who is/are credited for the formulation of the Cell Theory?

Answer: Matthias Schleiden, Theodor Schwann and Rudolf Virchow

Explanation: In 1839, Matthias Schleiden and Theodor Schwann formulated the first two tenets of the Cell Theory. Later in 1855, it was further expanded by Rudolf Virchow.

Question: Which idea did Rudolf Virchow add to the Cell Theory?

Answer: All Cells arise from pre-existing cells

Explanation: The three tenets of Cell Theory are:
1. All living organisms are composed of one or more cells.
2. The cell is the basic unit of structure and organization in organisms.
3. Cells arise from pre-existing cells.

In the modern version, three more ideas have been included:
1. Energy flow occurs within the cells.
2. Heredity information (DNA) is passed on from cell to cell.
3. All cells have the same basic chemical composition.

Question: An organism begins its life as ________.

Answer: a single cell

Explanation: All the multicellular organisms begin life as a single cell. A fertilized single-celled egg multiplies into billions of cells to form a multicellular organism.