Question

Define cellular level of organisation , tissue level of organisation and organ level of organisation.

Answer 1

Hint: The human body's life processes are maintained at various levels of structural organisation. Chemical, cellular, tissue, organ, organ system, and organism levels are among them. Lower levels of organisation are the foundation for higher levels. As a result, molecules combine to form cells, cells combine to form tissues, tissues combine to form organs, organs combine to form organ systems, and organ systems combine to form organisms.

Complete answer:
Cell: The smallest unit of life capable of self-replication. Nucleic acid, cytoplasm, a cell membrane, and numerous other proteins and structures are commonly found.
Organ: A structure composed of various tissues that collaborate to perform physiological functions.
A group of organs and tissues that work together to perform specific functions is referred to as an organ system.
Tissues are groups of similar cells from the same origin that collaborate to perform the same function.

Using the circulatory system as an example, a red blood cell is a cell in this system, the heart's cardiac muscle is a tissue, the heart itself is an organ, and the organ system is the circulatory system.

An organism is organised into four levels: cells, tissues, organs, and organ systems.
Level 1:Cells
The cellular level is the most fundamental level of organisation. A cell is the fundamental unit of life and the smallest unit capable of reproducing itself. While the structure and function of cells vary greatly depending on the organism, all cells share a few characteristics. Cells are composed of organic molecules, contain nucleic acids (such as DNA and RNA), are filled with cytoplasm, and have a lipid-based membrane. Cells also have many structures called organelles within their cytoplasm that perform various cellular functions.

Cells in bacteria and archaea (single-celled organisms) can be prokaryotic (without a nucleus) or eukaryotic (with nucleus-enclosing DNA) in plants, animals, protists, and fungi. Most cells in humans combine to form tissues, but some cells exist independently of solid tissues and have their own functions. A red blood cell discovered circulating in the bloodstream and transporting oxygen throughout the human body is an example of an independent cell.

Level 2 :Tissues
Tissues are groups of similar cells from the same origin that work together to perform a specific function. Basic tissues in humans are classified into four types. Connective tissues, such as bone tissue, are made up of fibrous cells that give organs shape and structure. Muscle tissue is composed of cells that can contract and allow animals to move.

The outer layers of organs, such as the skin and the stomach, are made up of epithelial tissues. Nervous tissue, such as nerve tissue, the spinal cord, and the brain, is made up of specialised cells that transmit information via electrochemical impulses.

Level 3: Organs
An organ is a structure composed of various tissues that carry out specific bodily functions. Most organs contain tissues such as parenchyma (which performs organ functions), stroma (organ-specific connective tissue), and epithelial. Organs can be solid or hollow, and their size and complexity vary greatly. Organs include the heart, lungs, and brain, to name a few.

Note: The organism level is the most complex level of organisation. An organism is a living being with a cellular structure that can perform all physiologic functions required for life on its own. All cells, tissues, organs, and organ systems in multicellular organisms, including humans, work together to maintain the organism's life and health.