Cell: The basic structural and functional unit of all living organisms; the smallest unit that can carry out life processes independently.
Tissue: A group of similar cells that work together to carry out a particular function.
Organ: A structure made up of different tissues working together to perform a specific function.
Organ system: A group of organs working together to carry out a major bodily function.
Epithelial tissue: A tissue type consisting of tightly packed cells that line surfaces and cavities; functions in protection, absorption, and secretion.
Organism: A living individual in which all organ systems work together to sustain life.
This definitions covers Key Definitions within Tissues, Organs and Organ Systems for GCSE Biology. Organizational hierarchy from cells to organ systems, tissue types in plants and animals, structure-function relationships, and system interactions It is section 9 of 15 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
Practice questions for Tissues, Organs and Organ Systems
What is the correct order of biological organisation from simplest to most complex?
Describe the functions of glandular tissue and epithelial tissue in animals.
Quick recall flashcards
What is a tissue?
A group of similar cells that work together to perform a specific function.
What is an organ?
A group of different tissues working together to perform a specific function.