Cells and Tissues Definition
Cells and Tissues: Living beings consist of cells and tissues. Cells and tissues are structurally present in all organisms and both have equal importance. A group of cells that have a similar structures and that function together as a unit is called a Tissue. Different types of tissues in all multicellular organisms are formed from a group of cells.
A cell is the smallest structural and functional unit of a living organism. Cells are the building blocks of all living beings. The cell consists of a cytoplasm enclosed within a plasma membrane. Each cell has one nucleus and membrane-bound organelles in the cytoplasm. Cell also contains biomolecules such as proteins, DNA and RNA, along with small molecules of nutrients and metabolites. Cell was first discovered by a British scientist Robert Hooke in 1665. He discovered plant cells by viewing the cell walls in its cork tissue under a microscope and observed honeycomb-like structures. He named these structures as cells. He described the cell as the basic unit of life. Cell is divided into two main types based on its cellular structure: Prokaryotes & Eukaryotes
Tissues are defined as a group of similar cells which function together. The concept of tissues was introduced by Xavier Bichat, a French anatomist and pathologist in 1801. He explained that tissues are a central element in human anatomy, concluding that organs are a collection of tissues. The tissues consist of similar types of cells which are specialized for a unique function. The tissues are present in both plants as well as animals. Tissues are present only in multicellular organisms.
Types of Cell Tissue
There are four main types of animal tissues –
- Epithelial tissue: Epithelial tissue provides mechanical strength and resistance to the underlying cells and tissue. These tissues are involved in sensory reception, excretion, filtration and other metabolic activities.
- Connective tissue: Connective tissue binds the cells and organs of the body together and functions in the protection, support, and integration of all parts of the body.
- Muscular tissue: Muscular tissue applies forces to different parts of the body by contraction. This tissue is composed of muscle cells. Muscle cells contract and expand due to which muscles facilitate various kinds of movements in the body.
- Nervous tissue: Nervous tissue makes up the nervous system. Nervous tissue is the group of cells in the nervous system which controls the movements of body, sends and carries signals to and from the different parts of the body.
Cells and Tissues Examples
The different examples of Cells are:
- Epithelial cells
- Red blood cells
- E. coli
- Xylem cells
- Palisade cells
The examples of Tissue are:
- Connective tissue
- Epithelial tissue
- Muscle tissue
- Nervous tissue
What is difference between cell and tissue?
The basic differences between cell tissue are tabulated below.
|Cells are the smallest structural and functional units of a living organism Cells are the building blocks of all living beings.||Tissues are group of cells which are specialized for a unique function.|
|Cells are found in both unicellular and multicellular organisms.||Tissues are found only in multicellular organisms.|
|Cell consists of different cellular organelles such as nucleus, mitochondria, lysosomes, Golgi apparatus, etc.||Tissues consists of similar types of cells which function together.|
|Cells are of two types – Eukaryotic cells and prokaryotic cells.||The main four types of tissues are- Epithelial tissue, Connective tissue, Muscular tissue, and Nervous tissue.|
|The function of cell includes Growth, metabolism, and reproduction.||A tissue has its own unique function.|
Cells and Tissues of Immune System
The Immune System is a complex network of cells, tissues, and organs that helps the body fight infections and other diseases and help in preventing or limiting infection. The immune system consists of a large network of cells, organs, proteins, and tissues throughout the body.
The immune system consists of:
- The spleen: The spleen is part of the lymphatic system. The Spleen fights the invading germs in the blood (the spleen contains infection-fighting white blood cells).
- White Blood Cells (leukocytes): White Blood Cells are made in the bone marrow and found in the blood and lymph tissue.
- Bone marrow: It is a soft tissue in the center of the bones that manufactures bone marrow stem cells which in turn produces red and white blood cells.
- Lymphatic system: This system consists of thin tubes and lymph nodes that run throughout the body. These thin tubes are called lymph vessels or lymphatic vessels. The lymphatic system plays role in fighting bacteria and other infections.
- Thymus: The thymus is located behind the breastbone. It plays an important role in immunity by producing immune cells. The main function of the Thymus is maturing T cells or T lymphocytes.
- Tonsils, Adenoids, and Appendix: Tonsils, Adenoids, and Appendix are part of the immune system. They are part of the lymphatic system which clears away infection and keeps body fluids in balance.
Cells and Tissues- FAQs
Q. What are Cells?
Ans. Cells are the smallest structural and functional units of a living organism Cells are the building blocks of all living beings.
Q. What are tissues?
Ans. Tissues are groups of cells that are specialized for a unique function.
Q. What is the difference between cells and tissue?
Ans. The difference between cells and tissue is provided above in this article.
Q. What are the 4 types of cell tissue?
Ans. There are 4 types of tissue: connective tissue, epithelial tissue, muscle tissue, and nervous tissue
Q. What are cells and tissues examples?
Ans. Example of Cell is Epithelial cells, Cardiomyocytes, Keratinocytes, Red blood cells, etc.
Example of Tissue is: Connective tissue, Epithelial tissue, Muscle tissue, Nervous tissue