Cell Biology

The cell was found for the first time in 1655, by an English scientist named Robert Hooke. This was such a significant discovery that it forever altered basic biology theory and research. So, how did the cell get discovered?

Robert Hooke was inspecting a dried portion of the cork tree with a crude light microscope. During this examination, he came across several microscopic compartments that he termed “cells.” Following that, several forms of research were undertaken over the next 175 years, eventually leading to the formation of the cell hypothesis as we know it today.

Fundamentals of Cellular Biology

The first such notion was suggested in 1838 by German botanist Matthias Jacob Schleiden and German scientist Theodore Schwann. This concept was proposed by Rudolf Virchow, a German scholar, in 1858.

Cellular Theory 

1. The cell is the basic functional and structural unit of life. Cells are the foundation of all living things.
2. All cells are formed through the division of pre-existing cells, a process known in biology as reproduction. Every cell in our body has genetic material that is passed down from generation to generation.
3. All of the basic physiological and chemical functions, such as development, repair, movement, communication, immunity, and digestion, are carried out by the cells.
4. The actions of the subcellular structures that comprise the cell determine the majority of the cell’s activities. These subcellular structures are made up of the plasma membrane, organelles, and, if present, the nucleus.

Cells

Here’s a fresh take on the cell introduction. All living organisms are made up of cells, which are the basic structural units. The presence of cells in our bodies is analogous to the bricks that comprise a construction. All of the bricks are assembled to form a structure. Similarly, all of the cells come together to create the body of an organism.

Cells are the fundamental structural and functional unit of life, and they are the building blocks of all organisms. The plasma membrane, organelles, and, in rare situations, a nucleus is all subcellular structures of the cell. The size of the cell varies from 1 to 100 micrometres.

Creation of Cells 

Every cell in our bodies is formed by the division of an existing cell. This is possible due to the genetic material in the cell. Genetic material is passed from one cell to the next throughout the reproduction process. Unlike non-living bricks, the cells of living animals are relatively sophisticated living structures. As a result, the cells can divide their genetic material and form two new cells.

Different  Types of cells

Cells are classified into two types: bacterial cells and eukaryotic cells. The major distinction between the two is the existence or absence of the nuclear membrane. Let’s take a closer look at the two types of cells.

1) A prokaryotic cell 

A prokaryotic cell has nuclear components but lacks a nuclear membrane. Organisms containing these types of cells are known as prokaryotes, where ‘pro’ refers to primitive and ‘karyon’ stands for nucleus. Prokaryotic cells are found in organisms such as bacteria and blue-green algae.

2) An Eukaryotic Cell is a type of eukaryotic cell that comprises nuclear material and a nuclear membrane. These cells are found in organisms called eukaryotes, with the ‘EU’ representing true and the ‘karyon’ standing for nucleus. Except for bacteria and blue-green algae, all living things contain eukaryotic cells.

Function Of Cell

According to biologists, a living organism must execute seven functions. These are as follows:

1. A living creature must react to changes in its environment.
2. A live creature must expand and grow during its life.
3. A living creature must be able to replicate or make copies of itself.
4. A living organism’s metabolism is essential.
5. A living creature must maintain homeostasis, or the ability to keep its internal environment stable in the face of external changes.
6. Cells are necessary for life to exist.
7. A living thing must pass on its traits to its descendants.

MCQs 

1. Cell biology is the study of cells, their types, structures, functions, and organelles.

a.Biology; b. Cell Biology; c. Microbiology; d. Microbiology;

Answer: b

2. In 1965, who was the first to discover the cell?

a.Robert Hooke b. Schwann c. Tatum d. De Bary 

Answer: a

3. The cell theory isn’t used in this case.

a.Algae b. Virus c. Bacteria d. Fungi 

Answer: b

Explanation: The virus does not fall within the cell theory.

4. Cell theory provided the following

a.Robert Hooke, b. Schwann and Schleiden, c. Darwin and Wallace, d. Darwin and Wallace

Answer: c

Cell theory was proposed by two German biologists M. Schleiden and T. Schwann, who stated that “the cell is the fundamental unit of life.” Cells are found in all plants and animals.”

5.In 1831, who discovered Nucleus?

a.Robert Hooke b. Robert Brown c. Rudolf Virchow d. T. Schwann

Answer: b

6.In animal cells, which of the following cell organelles is absent but present in plant cells?

a.Cell wall b. Cytoplasm c. Vacuoles d. Mitochondria a. 

Answer: a

7.The majority of the cell wall is made up of

a.Lipid b. Starch c. Cellulose d. Protein 

Answer: c

8.Digestion bags are found in which of the following cell organelles?

a.Nucleus b. Lysosomes c. Chloroplast d. Mitochondria 

Answer: b

Conclusion 

We conclude that Life’s smallest common denominator is cells. Some cells are self-contained entities, whereas others are components of multicellular organisms. Nucleic acids, proteins, carbohydrates, and lipids are the major types of organic compounds found in all cells.