Human Anatomy and Physiology
Anatomy is the science or study of body structures and how they relate to each other.
Physiology is the science or study of body functions and the work performed by the body parts.
- Levels of Organization: Explores the existence of a human body from elements and molecules and their combinations to form a whole person.
Physiology: The smallest units of matter (Carbon C, Hydrogen H, Oxygen O, Nitrogen N, Phosphorus P, Calcium Ca) that go through the chemical reactions and form molecules that are more stable chemical configurations. For example: glucose (blood sugar) and DNA, deoxyribonucleic acid (genetic material).
- Cellular level; In the next level, molecules combine to form cells which are the smallest living units of the human body. There are various types of body cells such as nerve cells, muscle cells, skin cells etc. These cells have various parts such as the plasma membrane, cytoplasm, nucleus, and organelles. Each part has a specific structure and function, which can be further explained in Cell Biology.
- Tissue level; A group of cells with similar properties or the materials around them make a specific tissue. In a human body, four basic types of tissues are present labeled as epithelial tissue, connective tissue, muscular tissue, and nervous tissue. As the name implies, they have the ability of forming specialized parts of the body and can be studied further under Histology.
- Organ level; Organs are the structures that are composed of two or more different types of tissues with a specific function and these organs have a specific shape. For example: stomach, liver, heart, kidneys etc. Further discussion on these topics will include details of their structure and functions.
- System level; A system consists of related organs with a common function. An example is the respiratory system, which helps us breathe with various parts such as the nose, trachea, pharynx, and lungs. Sometimes an organ can be a part of more than one system. For instance, the pharynx belongs to the respiratory system as well as the digestive system.
- Organism level; It is the most advanced level of organization where all the parts of the human body work together to constitute an organism. All the systems work together to maintain an equilibrium or balance in the body known as homeostasis. All these systems are explained in the anatomy and physiology course.