Introduction to Anatomy

• Anatomy involves the structural organization of the body at different levels.
• Microscopic and gross anatomy are the two forms of anatomy.

Microscopic Anatomy

• Cytology studies the structure and function of cells.
• Histology studies biological tissues.

Gross Anatomy

• Gross anatomy involves studying structures visible to the naked eye.
• Surface anatomy focuses on structures that can be seen and felt from the outside.
• Regional anatomy focuses on specific areas of the body.
• Systemic anatomy focuses on structures working together to accomplish certain functions.

Levels of Organization

• The levels of organization in the body, from smallest to largest, are: chemical/molecular, cells, tissues, organs, organ system, and organism.

Molecules of the Body

• The molecules that make up the body are primarily carbon, hydrogen, oxygen, and nitrogen (CHON), constituting over 99%.

Organ Systems

• Different organ systems include: cardiovascular, endocrine, lymphatic, nervous, respiratory, muscular, digestive, skeletal, urinary, integumentary, and reproductive.

Homeostasis and Disease

• Homeostasis is the baseline or normal range of the internal environment.
• Diseases are deviations from homeostasis, usually leading to illness or sickness.

Pathology

• Pathology is the study of diseases, including their causes and effects.

Anatomical Positions

• Supine position involves lying on the back with the face up and palms facing up.
• Prone position involves lying on the stomach with the face down and palms facing down.

Anatomical Directions

• Superior (anatomically) means closer to the head.
• Inferior (anatomically) means closer to the feet.
• Posterior means closer to the back.
• Anterior means closer to the front.
• Medial means towards the body's midline.
• Lateral means away from the body's midline.
• Proximal means toward an attached base or higher up (e.g., elbow is proximal to the wrist).
• Distal means further away from the body or closer to the end of a limb (e.g., wrist is distal to elbow).

Anatomical Planes

• The transverse plane divides the body into an upper and lower half.
• The frontal plane divides the body into a front and back section.
• The sagittal plane divides the body into a left and right section.
  • Midsagittal divides the body equally into left and right sides.
  • Parasagittal divides the body unequally into left and right sides.
• An oblique plane is any plane not fitting into sagittal, frontal, or transverse categories and is diagonally oriented or slanted.