1. The Human Body: An Orientation

2. Overview of Anatomy and Physiology
Anatomy – the study of the structure of body parts and their relationships to one another …. what things look like
Gross or macroscopic – large; seen with eye
Microscopic – small; need microscope to see
Developmental – changes that occur over time
Physiology – the study of the function of the body’s structural machinery …. how a body part works

3. Gross Anatomy
Regional – all structures in one part of the body (such as the abdomen or leg)
Systemic – gross anatomy of the body studied by an entire system (i.e. digestive or skeletal system )

4. Microscopic Anatomy
Cytology – studies cell structure and its interactions with other cells. One cell only
Used to analyze cells to diagnose disease
Also known as cell biology
Histology – study of the microscopic anatomy of tissues made of a group of similar cells, like muscles or skin.
Many cells of the same type

5. Developmental Anatomy
Traces structural changes throughout life (puberty, growing old)
Embryology – study of developmental changes of the fetus before birth

6. Specialized Branches of Anatomy
Pathological anatomy – study of structural changes caused by disease causing organisms like bacteria and fungi
Radiographic anatomy – study of internal structures visualized by X-ray, MRI, PET scans, CT scans and ultrasound
Molecular biology – study of structures at a sub-cellular level like DNA damage caused by cancer or protein structure deformities like sickle-cell anemia

7. Physiology Aspect of Studying Anatomy
Understanding physiology also requires a knowledge of physics, which explains electrical currents, blood pressure, and the way muscle uses bone for movement
Also requires knowledge of chemistry where gas laws help to explain gas exchange in our lungs

8. Principle of Complementarity
Function always reflects structure
What a structure can do depends on its specific form
“The way something looks is related to how the structure works.”
In anatomy, we study the structure of a body part, and using our understanding of physics and chemistry, we try and determine how it functions.

9. Levels of Structural Organization
Chemical – atoms combined to form molecules
Cellular – cells are made of molecules
Tissue – consists of similar types of cells
Organ – made up of different types of tissues
Organ system – consists of different organs that work closely together
Organism – made up of the organ systems

10. Levels of Structural Organization
Smooth muscle cell
Molecules
Cellular level Cells are made up of molecules 2
Atoms 1
Chemical level Atoms combine to form molecules
Smooth muscle tissue
Heart 3
Tissue level Tissues consist of similar types of cells
Cardiovascular system
Blood vessels
Epithelial tissue
Smooth muscle tissue
Blood vessel (organ) 6
Organismal level The human organism is made up of many organ systems
Connective tissue 4
Organ level Organs are made up of different types of tissues 5
Organ system level Organ systems consist of different organs that work together closely
Figure 1.1

11. Organ Systems of the Body
Integumentary system
Forms the external body covering
Composed of the skin, sweat glands, oil glands, hair, and nails
Protects deep tissues from injury and synthesizes vitamin D

12. Organ Systems of the Body
Skeletal system
Composed of bone, cartilage, and ligaments
Protects and supports body organs
Provides the framework for muscles
Site of blood cell formation
Stores minerals

13. Organ Systems of the Body
Muscular system
Composed of muscles and tendons
Allows manipulation of the environment, locomotion, and facial expression
Maintains posture
Produces heat

14. Organ Systems of the Body
Nervous system
Composed of the brain, spinal column, and nerves
Is the fast-acting control system of the body
Responds to stimuli by activating muscles and glands

15. Organ Systems of the Body
Cardiovascular system
Composed of the heart and blood vessels
The heart pumps blood
The blood vessels transport blood throughout the body

16. Organ Systems of the Body
Lymphatic system
Picks up fluid leaked from blood vessels and returns it to blood
Disposes of debris in the lymphatic stream
Houses white blood cells involved with immunity

17. Organ Systems of the Body
Respiratory system
Composed of the nasal cavity, pharynx, trachea, bronchi, and lungs
Keeps blood supplied with oxygen and removes carbon dioxide

18. Organ Systems of the Body
Digestive system
Composed of the oral cavity, esophagus, stomach, small intestine, large intestine, rectum, anus, and liver
Breaks down food into absorbable units that enter the blood
Eliminates indigestible foodstuffs as feces

19. Endocrine System Organ System Overview Secretes regulatory hormones
Controls growth, like
Controls reproduction
Controls metabolism
human growth hormone
like the pancreas creating insulin to control sugar

20. Organ Systems of the Body
Urinary system
Composed of kidneys, ureters, urinary bladder, and urethra
Eliminates nitrogenous wastes from the body
Regulates water, electrolyte, and pH balance of the blood

21. Organ Systems of the Body
Male reproductive system
Composed of prostate gland, penis, testes, scrotum, and ductus deferens
Main function is the production of offspring
Testes produce sperm and male sex hormones
Ducts and glands deliver sperm to the female reproductive tract

22. Organ Systems of the Body
Female reproductive system
Composed of mammary glands, ovaries, uterine tubes, uterus, and vagina
Main function is the production of offspring
Ovaries produce eggs and female sex hormones
Remaining structures serve as sites for fertilization and development of the fetus
Mammary glands produce milk to nourish the newborn