Human Anatomy: Refers to the structure of the body and its parts.
Human Physiology: Refers to the function of the body and its parts.
Note: Structure determines function. An understanding of physiological concepts requires a strong knowledge of both microscopic and macroscopic anatomy.
Levels of Organization
Understanding anatomy and physiology (A & P) necessitates a focus on the body as a whole and its interconnected systems. The course begins with the introduction of basic terminology and moves onto the chemical organization of the body.
Subsequent chapters will explore levels of organization including:
- Cellular Level: Study of cells, the basic unit of life.
- Tissue Level: Study of tissues, groups of cells working together.
- Organ Level: Study of organs, groups of tissues functioning together.
- Organ Systems Level: Study of organ systems, groups of organs working together.
- Organism Level: Entire living being made up of interconnected systems.
Definitions of Terms
Atom: The smallest unit of matter that combines to form chemicals.
Chemical: A substance with a distinct molecular composition.
Organelle: Structural units within cells that serve specific functions.
Cell: The basic structural unit of living organisms.
Tissue: A group of cells working together to perform a specific function.
Organ: A group of tissues working together to perform a specific function.
Organ System: A group of organs working together to perform a specific function.
Organism: A group of systems working together to maintain life.
Understanding Levels of Organization
In A & P, it is crucial to understand what each term means and to be able to define these terms using personal wording along with examples.
Examples for Practice: Identify the level of organization for the following terms:
- Blood: Organism
- Na+ (Sodium ion): Atom
- Nervous System: Organ system
- Stomach: Organ
- Bone Tissue: Tissue
- Femur: Organ
- H₂O (Water): Chemical
- Neuron: Cell
- Protein: Chemical (or molecule)
- Spinal Cord: Organ
- Lymphatic System: Organ system
- Ribosome: Organelle
- Mitochondrion: Organelle
- Endocrine System: Organ system
- White Blood Cell: Cell
- Human: Organism