Describe the meaning of the terms: cell, tissue, organ, organ system and organism as illustrated by examples given in the syllabus

Sourav PanNovember 14, 2024

Answered step-by-step

The terms cell, tissue, organ, organ system, and organism represent different levels of biological organization in living organisms. Here’s a description of each term along with examples:

1. Cell

• Definition: A cell is the smallest structural and functional unit of life. It can exist as a single-celled organism or as part of a multicellular organism.
• Example: A red blood cell is a specialized cell responsible for transporting oxygen throughout the body.

2. Tissue

• Definition: A tissue is a group of similar cells that work together to perform a specific function. Tissues are composed of cells that share common characteristics and functions.
• Example: Muscle tissue is made up of muscle cells (myocytes) that contract to facilitate movement.

3. Organ

• Definition: An organ is a structure composed of two or more types of tissues that work together to perform specific functions within an organism.
• Example: The heart is an organ made up of cardiac muscle tissue, connective tissue, and epithelial tissue, all working together to pump blood throughout the body.

4. Organ System

• Definition: An organ system is a group of organs that work together to carry out complex functions necessary for the survival and health of the organism.
• Example: The digestive system includes organs such as the stomach, intestines, liver, and pancreas, all collaborating to break down food, absorb nutrients, and eliminate waste.

5. Organism

• Definition: An organism is any living entity that can function independently. It may be unicellular (composed of a single cell) or multicellular (composed of many cells).
• Example: A human being is a multicellular organism composed of various organ systems working together to sustain life.

Summary

In summary, these terms illustrate the hierarchical organization of life:

• Cells form tissues,
• Tissues combine to create organs,
• Organs work together in organ systems,
• Organ systems make up an organism.