Unit 1 Anatomy And Physiology

UNIT 1: INTRODUCTION TO ANATOMY
Introduction
What is Anatomy?
Anatomy is the science that studies the body.

What is Physiology?
Physiology is the science that studies the function of the body

What is homeostasis?
Anatomy and Physiology are closely related because each tissue, organ, system in the body has a function. All the body organs and systems in your body work to maintain the proper function of your body in equilibrium (homeostasis) using positive and negative feedback mechanisms
• Example of positive feedback: More and more uterine contractions will occur during childbirth. The body will work to increase the number of contractions until the mother delivers the baby
• Example of negative feedback: If the environment is too hot the

person will sweat until the body temperature drops. The body will work to decrease the body temperature

Body organization
How is the body organized?
There are different levels of organization. The basic level of organization is the chemical level. Everything is this world is made of chemicals. The rug, chair, book, pencil, oranges, humans etc. are composed of chemicals.

• Chemicals form molecules and molecules form compounds.

Some of these compounds can form a cell and the cells form humans. The cells are considered the smallest functional unit of the body therefore if we use the cell as the starting point:

• Group of cells form a tissue.
• Group of tissues form organs
• Group of organs form systems
• Group of systems form an organism.

There are different organisms like humans, dogs, plants etc.

The Anatomical Position
What is the anatomical position?
The anatomical position is used to provide a point of reference when referring to the human body. The anatomical position assumes the
• Person is standing facing forward
• Palms are facing forward
• Arms on each side of the body
• Legs slightly open

Body Planes
What is a body plane?
Using the anatomical position, a body planes is an imaginary layer that cut the body in half.
Which ones are the body planes?
• Transverse plane: divides the body in superior and inferior
• Sagittal plane: divides the body right in the middle left and right (50% and 50%).
• Parasagittal plane: divides the body in left and right but the division might be 70% and 30%, 40% and 60% etc
• Coronal plane: sometimes called frontal plane divides the body in anterior and

posterior

Body cavities
Which ones are the body cavities?
• Cranial cavity: The brain is located in this cavity
• Spinal cavity: The spinal cord is located in this cavity
• Thoracic cavity (chest): Heart, lungs, esophagus, trachea etc are located in this cavity
• Abdominal cavity: It is the cavity below the diaphragm. Some organs located in the abdominal cavity are the pancreas, spleen, intestines, stomach, kidneys, liver.
• Pelvic cavity: This cavity contains organs that belong to the reproductive system such as uterus, ovaries, prostate, fallopian tube etc.

Abdominal quadrants and regions
The abdomen can be divided in quadrants and regions
Which ones are the body quadrants?
The abdomen can be divided in four quadrants:
Upper right Upper left
Lower right Lower left

Which ones are the abdominal regions?
The abdomen can be divided in nine abdominal regions:
Hypogastric right Epigastric Hypogastric left
Lumbar right Umbilical Lumbar left
Iliac or Inguinal right Hypogastric Iliac or Inguinal left