#1 Introduction to Anatomy & Physiology

Every momoment you make, and every new day that you live to see, is the result of a collection of systems working together to fuction properly.

ANATOMY
The study of the structrue and relationships between body parts.

PHYSIOLOGY
The Science of how those parts come together to function, and keep that body alive.

 

They're all processes that we can understand through ANATOMY and PHYSIOLOGY.

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• History of Anatomy

For centuries, the dissection of human bodies was very taboo in many societies.

It wasn't until the 17th and 18th centuries that certified anatomists were allowed to perform tightly regulated human dissections.

Today, students of anatomy and physiology still use educational cadavers to learn, in person and hands-on, what's inside a human body by dissection them.

 

• Physiology: How parts Funtion

Blood flows in one direction through your heart simply because its valves prevent it from backward.

In the same way, your bones are strong and hard and this allows them to protect and support all your soft parts.

 

• Complementarity of Structure & Fuction

It hods true through every level of your body's organization, from cell to tissue to system.

And it begins with the smallest of the small: atoms.

 

• Hierachy of Organization

The next level up from the chemistry of atoms and molecules includes the smallest units of living things - cells.

All cells have some basic functions in common, but they also vary widely in size and shape, depending on their purpose.

Cells group with similar cells to form the next level of organization - tissues, like muscles, membranes and cavity linings, nervous, and connective tissues.

When two or more tissue types combine, they form organs - the heart, liver, lungs, skin and etcetera that perform specific functions to keep the body running.

Organs work together and combine to get things done, forming organ systems. It's how, like, the liver, stomach, and intestines of your digestive system all unite to take that burrito from plate to pooper.

All those previous levels combine to form the highest level of organization - the body itself.

 

This ability of all living systems to maintain stable, internal conditions no matter what changes are occurring outside the body is called homeostasis, and it's another major unifying theme in anatomy and physiology.

 

Everyone's ultimate cause of death is the extreme and irreversible loss homeostasis.

So the real result of such an injury - the actual cause of death - is the loss of homeostasis.

 

• Directional Terms

Anatomy has developed its own standardized set of directional terms that described where one body part is in relation to another.

Anatomical Position:
body is erect and facing forward, with arms at the sides and palms forward

Sagittal Plane (median plane) comes down vertically and divides a body or organ in left or right parts.

Parasagittal Plane:
to describe any plane parallel or adjacent to a given sagittal plane.

Coronal Plane (frontal plane) splits everything vertically into front and back.

Transverse Plane (horizontal plane) divides the body top and bottom.

Axial Parts: head, neck, and body

Appendicular Parts: arms and legs

Anterior or Ventral: front of the body

Posterior or Dorsal: back of the body

Superior or Caranial: towards the top

Infferior or Caudial: towards the bottom

Medial:
Structures toward midline

Lateral:
Structures farther away from midline

Proximal:
towards the trunk

Distal:
further from the trunk