Questions And Answers On Fundamentals of Cell Biology
Question: What are the building blocks of life?
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?
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?
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?
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?
Explanation: Prokaryotes are single-celled organisms (unicellular) that were the first ever life forms on Earth.
Question: Are all unicellular organisms prokaryotes?
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?
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?
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?
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 ________.
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.