Organization of the Human Body

1. Organization of the Human Body Chapter 1

2. The Study of anatomy and physiology has paralleled the development of cultures, religion, and technology. Ancient civilizations such as the Maya and Incas are believed to have preformed surgeries Imhotep, 2500 BC: recorded some of the earliest information on surgery Aristotle, 500 BC: founder of comparative anatomy Herophilus, 500 BC: “father of anatomy” described the diagnostic value of the pulse Erasistratos, 500 BC: contributed to the understanding of the anatomy of the brain, and noted the difference between motor and sensory nerves

3. History of Anatomy and Physiology Galen, year 0: “First Great Anatomist”, his writings remained unchallenged for 1500 years. Conformed his anatomic findings to theological principles Andreas Vesalius, 1500: “Father of Modern Anatomy”, corrected Galen’s mistakes. Dissected human cadavers Ambroise Pare’, 1500: “Greatest Surgeon of the 16th century”, first to ligate vessels to control bleeding after amputations

4. Terms Anatomy: is the study of the structure and morphology of the body and its systems. Physiology: is the study of the functions of the cells, tissues, and organs of the body Pathophysiology: – is the study of disease and disorder of the human body. (Knowledge of anatomy and physiology is essential to understand these disorders.

5. Anatomic Position When a person is in anatomic position, the body is erect and facing forward with arms supinated at the side and palms of the hands and feet facing forward. Supine- face up, palms up Prone- face down, palms down

6. Anatomic Position

7. Directional Terms Superior – toward the head Inferior – toward the feet Anterior – front Posterior – back

8. Directional Terms cont. Medial – toward the midline of the body Lateral - toward the side of the body Proximal – nearest the point of origin of one of its parts Distal - away from the point of origin Superficial- nearer the surface Deep- farther away from the surface

9. Geometric Planes

10. Geometric Planes • The body is sectioned into imaginary geometric planes: • Saggital - divides the body or parts into right and left sides • Midsaggital(median plane)– divides the body into equal right and left sides • Transverse(horizontal plane)- divides the body or parts into upper and lower portions • Coronal(frontal plane)- divides the body or parts into anterior and posterior portions • Cross section – a transverse cut that is at angles to the long axis of the organ

11. Saggital

12. Transverse

13. Coronal

14. Reference Points • Reference points are used to identify key anatomic landmarks • Epicondyle • Condyle • Foramen • Fossa • Trocanter • Triangle of Calot • Hesselbach’s triangle • Trigone of bladder • Ligament of Treitz • Hepatic flexure • Splenic flexure

15. Quadrants When making clinical diagnoses surgeons frequently use quadrants to indicate the area of bodily pain RUQ – right upper quadrant RLQ – right lower quadrant LUQ – left upper quadrant LLQ – left lower quadrant

16. Quadrants

17. Nine Regions • Two saggital planes and two transverse planes divide the abdomen into nine regions • Right Hypochondrium • Left Hypochondrium • Epigastrium • Right Lumbar • Left lumbar • Umbilical • Right iliac • Left iliac • Hypogastrium

18. Nine Regions

19. Major Body Cavities The body is divided into two major cavities: Dorsal Cavity – Posterior division of the body. further subdivided into the cranial cavity and the spinal cavity Ventral Cavity – Anterior division of the body. further subdivided into the thoracic and abdominopelvic cavities

21. Body Cavities

22. Body Cavities Cranial cavity: contains the brain Spinal Cavity: contains the spinal cord The membranes that line the cranial and spinal cavities are called the meninges Thoracic cavity: further subdivided into the… • mediastinum: esophagus , thymus gland, trachea • Pericardial cavity: contains the heart (within its pericardial sac) • Pleural cavities: contains the lungs Abdominopelvic cavity: also called the peritoneal cavity is further subdivided into the… • Abdominal cavity: contains the stomach, liver, gallbladder, spleen, pancreas, small intestines, and colon • Pelvic cavity: sigmoid colon, rectum, bladder, and internal reproductive organs

24. Diaphragm Separates the thoracic cavity from the abdominopelvic cavity Is the most important muscle in breathing

25. Peritoneum • The peritoneum is a serous membrane that lines the abdominal cavity • Parietal peritoneum: lines the wall of the abdominoplevic cavity • Visceral peritoneum: covers the organs in the abdominopelvic cavity • Peritoneal space: small space between the two layers, contains serous fluid and reduces friction

26. Mesentery • Mesentery: a fold of peritoneum that invests the intestines and attaches them to the posterior abdominal wall • Omentum : a double fold of peritoneum that is divided into the greater omentum and the lesser omentum • Greater omentum: attaches to the greater curvature of the stomach and hangs loosely downward covering the intestines • Attaches to the lesser curvature of the stomach and duodenum

27. Organization of the Human Body The levels of organization progress from the least complex (chemical level) to the most complex (organism level) Atoms and molecules are referred to as the chemical level

29. Organization of the Human Body Cells are the smallest living units of structure and function in our body Tissues are an organization of many similar cells Organs are an organization of several different kinds of tissues

30. Organization of the Human Body Systems are varying numbers and kinds of organs working together to perform complex functions The body is a unified and complex assembly of interactive components

31. Body Systems • A group of organs arranged to perform a more complex function • There are 11 major organ systems in the human body: • Integumentary • Skeletal • Muscular • Nervous • Endocrine • Circulatory (cardiovascular & peripheral vascular) • Lymphatic • Digestive • Respiratory • Genitourinary • Reproductive

32. Integumentary system • Largest organ system which Includes: • Skin • Sweat glands • Sebaceous glands • Hair • Nails • Functions: • First line of defense • Protects underlying tissues and structures • Insulates • Regulation of body temperature • Cutaneous sensation • Detects Pressure • Contains sweat & sebaceous glands • Synthesis of Vitamin D • Absorption sigh for topical medications

33. Skeletal System • Includes: • Skeleton • Ligaments • Tendons • Cartilage • Function: • Support • Providing basic body shape • Aids in movement of the body • Sight of hematopoeisis in red bone marrow • Stores fat in Yellow bone marrow • Protects internal organs • Tendons attach muscle to bone • Ligaments attach bone to bone • Cartilage allows articulation and attachment of bones to • other bones

34. Muscular System • Includes: • Skeletal muscle (Voluntary/striated muscle) • Smooth muscle (involuntary/non striated muscle) • Cardiac muscle • Function: • Movement • Maintains body posture • Heat production • Aids flow of blood through the body • Pushes food through the gastrointestinal tract (GI) • by way of parastalsis

35. Nervous system • Includes: • Brain • Spinal cord • Cranial nerves • Peripheral nerves • Functions: • Memory • Special senses • Receives and interprets sensory information from internal and external stimuli • Sends motor impulses

36. Nervous System cont. CNS (Central nervous system): Consists of the brain and spinal cord PNS (Peripheral nervous system): Comprises the nerves *SNS (Somatic Nervous system): Cranial nerves connected the brain to the skin and skeletal muscle and initiate voluntary movements and responses *ANS (Autonomic Nervous system): Cranial and spinal nerves connect the brain to visceral organs initiate involuntary responses *Sympathetic: “fight or flight” *Parasympathetic: Calms the body, conserves energy, restores homeostatic balance Visceral: Internal organs

37. Endocrine system • Includes: • Pituitary gland (Master gland) • Thyroid gland • Parathyroid gland • Pancreas • Thymus gland • Adrenal glands • Testes • Ovaries • Functions: • Secretes hormones that affect metabolism and many functions • of the body • Target tissue: group of cells to be affected by a particular hormone • The endocrine system works closely with the nervous system. • The nervous system provides rapid response while the endocrine system • Provides slower response, but longer lasting results

38. Circulatory system • Includes: • Cardiovascular system: Heart, coronary arteries, aorta, pulmonary arteries and veins, superior and inferior vena cava • Peripheral vascular system: All arteries, veins and capillaries outside of the heart • Functions: • Heart pumps to circulate blood • Blood transports oxygen to body cells • Blood transports waste for elimination • Blood transports hormones • Helps maintain normal body temperature

39. Lymphatic system • Includes: • Lymph fluid • Lymph vessels • Lymph nodes • Spleen • Thymus • Functions: • Lymphatic system also called the Immune system • Filters out microorganism and foreign body substances • Maintains fluid levels in interstitial spaces to prevent Edema • Absorption of fat in the intestinal tract • Edema: accumulation of excess fluid in interstitial spaces • Lymphocytes: cells of the lymphatic system

40. Digestive system • Includes: • Mouth • Teeth • Tongue • Salivary glands • Pharynx • Esophagus • Stomach • Liver • Gallbladder • Biliary duct system • Pancreas • Small intestine • Colon • Function: • Mechanical and chemical breakdown of food into simpler forms that can be used by body cells a energy • Transports food out of the body

41. Respiratory system • Includes: • Nasal cavity • Pharynx (throat) • Larynx (voice box) • Trachea (wind pipe) • Lungs • Bronchi • Bronchioles • Alveoli • Function: • Exchange of oxygen and carbon dioxide between the blood and inhaled air

42. Genitourinary system • Includes: • Kidneys • Ureters • Urinary bladder • Urethra • Functions: • Maintains water & electrolyte balance • Filters blood removing waste • Elimination of waste and excess fluid through formation of urine

43. Female Reproductive System • Includes: • Ovaries • Fallopian tubes • Uterus • Vagina • Clitoris • External genitalia (vulva) • Breast • Functions: • Production of ova • Transportation of fertilized ova into uterus • Support developing embryo • Delivery of fetus • Milk production • Menstruation if ova is not fertilized • Formation of sex characteristics

44. Male Reproductive system Includes: Scrotum Testes Epididymis Vas deferens Seminal vesicles Prostate gland Bulbourethral glands Urethra Penis Function: Production of spermatozoa Responsible for transporting the spermatozoa into the female reproductive tract

45. Homeostasis !!!! Homeostasis: is the coordination of all the various functions of the body to maintain a normal internal environment.