An Introduction to Human Anatomy

Definitions – Anatomy

• the study of the names of the structures in the human body

– Physiology• the study of the functions of body parts

Variation in Human Structure• No 2 humans are exactly alike

– Examples• Some people completely lack certain organs

• Most have 2 kidneys

• Situs inversus: organs are flipped

Fields in Anatomy– Microscopic anatomy: the study of the form of

normal structures seen under the microscope– Gross anatomy:involves structures that are big

enough to be observed with the naked eye. – Radiologic anatomy: study of the anatomy of tissues

based on their visualization on x-ray films

– Regional anatomy: study of anatomy based on regions or divisions of the body and emphasizing the relations between various structures

– Systemic anatomy: concerned with the structure and function of the various systems

Levels of Organization

Chemical Level– Atom

• Smallest unit of a specific substance

– Molecule• 2 or more atoms bonded together

Molecular Level– Carbohydrates

• Sugars and starches

– Lipids• Fats and oils

– Proteins (formed from amino acids)• Enzymes, hormones, antibodies

• Basis of life

– Nucleic acids (formed from nucleotides)• DNA, RNA

• Determine what proteins are made

Organization of Molecules, Etc.– Molecules are organized into cells

• Basic unit of a living organism

– Cells are grouped together into tissues• Groups of cells having the same function

– Organs are groups of different tissues• Special functions

– Organs are grouped into organ systems • Groups of organs working together

Early Anatomists– Aristotle

• One of the earliest to write about anatomy

– Claudius Galen• Medical textbook was the basis for teaching for

1500 years

The Birth of Modern Anatomy– Andreus Vesalius

• Pioneer of modern anatomy• Published the first atlas of anatomy

– De Humani Corporis Fabrica (On the Structure of the Human Body)

The Discovery of Microscopic Anatomy– Antony van Leeuwenhoek (1632 – 1723)

• Invented a microscope capable of visualizing single cells

– Robert Hooke (1635 – 1703)• Developed the first practical compound microscope

• Observed “cells”

– Microscopes were improved in the 19th century• Matthias Schleiden (botanist) and Theodor Schwann

(zoologist) - cell theory

Survey of the Human Body

Organ Systems

There are 11 organ systems and each works with the others to allow your body to

function properly.

Integumentary System

Skeletal System

Muscular System

Nervous System

Endocrine System

Cardiovascular System

Lymphatic System

Respiratory System

Digestive System

Urinary System

Male Reproductive System

Female Reproductive System

The Language of Anatomy

Descriptive Terms Used in Superficial Anatomy

Anatomical Position– Standing– Facing forward– Palms forward

Anatomical regions– Cephalic - head

– Cervical - neck

– Thoracic - chest

– Abdominal - stomach

– Inguinal - groin

– Lumbar – between diaphragm and pelvis

– Brachial - arms

– Femoral - thighs

– Abdominopelvic areas: contains the stomach, liver, spleen,gallbladeer, kidneys, and most of the small and large intestines. It also contains urinary bladder and internal reproductive organs.

Abdominopelvic Quadrants

Abdominopelvic Regions

Directional Terms

Sections and Planes

Body Cavities

Body Cavity Linings– Body cavities have membranes that line the cavity

themselves as well as cover the organs.• Visceral and parietal

• The space between the two is filled with fluid.

– Pleural cavity• Pleura – membrane that surrounds the lungs

• Pleural fluid

– Pericardial cavity• Pericardium – double membrane sac that encloses the heart

• Pericardial fluid

– Abdominopelvic cavity• Peritoneum – membrane that lines abdomic and pelvic cavities

• Peritoneal fluid

Pleural Cavities

Pericardial Cavity

Body Cavities