Review Tip

2. Review Tip Anatomy and Physiology is the most demanding chapter but one that provides a feeling of accomplishment when you have completed it. Study all the figures and tables. The national exams generally contain at least two questions on each body system. The endocrine system, with the glands and hormones, tends to be the most difficult. (Remember, during the exam, do not spend too much time on any one question.) Schedule your study time by body system. Limit the number you tackle at each session. Reward yourself when you finish this chapter!

3. Overview Knowledge of anatomy and physiology is a foundation for many areas of medical assisting and medical administrative specialization. It is used in both administrative (e.g., insurance billing and coding) and clinical practice (e.g., patient assessment). With a solid understanding of the structure and function of body parts, you will be able to analyze questions and to solve problems. Anatomy—the study of body structure Physiology—the study of body function Pathology—the study of abnormal changes in body structure or function, usually caused by disease

4. Overview, cont’d. Body Ordering Living things are arranged from simple to complex: ■ Chemicals—atoms and molecules ■ Cells—structural and functional units of life ■ Tissues—groups of cells with similar structures and functions (such as connective tissue) ■ Organ—group of tissues working together to perform a function (e.g., kidney) ■ Systems—group of organs working together to perform a set of related functions • Integumentary system—skin and related structures that contain and protect • Skeletal system—bones and related structures that support • Muscular system—muscles and related structures that accommodate movement

5. Overview, cont’d. • Nervous system—nerves and related structures that receive stimuli and initiate responses • Sensory system—sensory neurons and special sense organs that detect the environment and changes • Endocrine system—glands and related structures that produce hormones • Cardiovascular system—heart and blood vessels that circulate blood to transport nutrients and remove waste from tissues • Lymphatic system—lymph, lymph nodes, and related organs that protect against and fight disease • Respiratory system—lungs and related structures that transport oxygen (O2) and remove carbon dioxide (CO2) • Digestive system—mouth, esophagus, stomach, intestines, liver, gallbladder, and pancreas, which ingest and process food and eliminate solid waste products

6. Overview, cont’d. • Urinary system—kidneys, ureters, bladder, and urethra, which remove nitrogen-type waste and regulate water balance • Reproductive system—gonads (ovaries or testes) and related sex organs and structures that reproduce the species ■ Body (organism)—group of systems working together to maintain life

7. Overview, cont’d. Figure 6-1. Body ordering.

8. Overview, cont’d. Anatomic Descriptors The national exams contain several questions related to the location of specific organs and other anatomic structures. Directional terms of the body help describe and locate these structures.

9. Overview, cont’d. Body Directions and Planes Figure 6-2 shows the imaginary planes dividing the body: frontal (or coronal) plane, the sagittal plane, and the transverse (or horizontal) plane. The body is in anatomic position—upright, face forward, and arms down and slightly away from the sides with palms forward and feet and legs parallel. Other important descriptors of body directions are as follows: superior (cranial or cephalic), anterior (ventral), posterior (dorsal), inferior (caudal), proximal, distal, medial, and lateral.

10. Overview, cont’d. Figure 6-2. Body planes and directions.

11. Overview, cont’d. Body Cavities The locations of organs are usually described as being in a specific body cavity or space. Directional terms (e.g., posterior, anterior, inferior) are used to determine the position in relation to other organs also found in that cavity. Figure 6-3 illustrates the following body cavities: ■ Cranial cavity—contains the brain ■ Spinal cavity—contains the spinal cord; runs continuously from the brainstem in the cranial cavity to the end of the spinal cord. ■ Thoracic cavity—contains the heart, lung, and large blood vessels; it is separated from the abdominal cavity by the diaphragm; within the thoracic cavity lies the mediastinum, a smaller cavity between the lungs that contains the heart and large blood vessels

12. Overview, cont’d. ■ Abdominal cavity—contains the stomach, most of the intestines, the kidneys, liver, gallbladder, pancreas, and spleen; it is separated from the thoracic cavity (superior) by the diaphragm and from the pelvic cavity (inferior) by an imaginary line across the top of the hip bones ■ Pelvic cavity—contains the urinary bladder, rectum, and internal organs of the male/female reproductive systems; it is separated from the abdominal cavity (superior) by an imaginary line between the hip bones

13. Overview, cont’d. Figure 6-3. Body cavities.

14. Overview, cont’d. Abdominal Quadrants and Regions The abdomen is divided into four quadrants: right upper right lower left upper left lower The abdomen is also divided into nine regions: right hypochondriac left hypochondriac epigastric hypogastric right lumbar left lumbar right iliac left iliac umbilical

15. Overview, cont’d. Figure 6-4. Abdominal divisions. A. Quadrants. B. Regions.

16. Overview, cont’d.

17. Overview, cont’d. Basic Body Processes For the body to grow, repair itself, and maintain equilibrium, certain processes must occur. Metabolism, fluid balance, and homeostasis are basic processes that take place or begin at the cell level.

18. Overview, cont’d. Metabolism Metabolism = energy transformation in living cells. This transformation occurs in two metabolic processes: ■ Anabolism—builds up and repairs cells ■ Catabolism—breaks down cells

19. Overview, cont’d. Fluid Balance Fluid balance = regulation of the amount and composition of the body’s fluids. The two major divisions of body fluid are: ■ Extracellular fluid—body fluid outside the cell ■ Intracellular fluid—body fluid inside the cell

20. Overview, cont’d. The concentration of the fluid affects fluid movement and balance. The three basic solution concentrations are: ■ Isotonic solution—this has the same concentration as intracellular fluid and moves in and out of the cell at the same rate; normal saline (0.9% salt) and 5% dextrose are examples of manufactured isotonic solutions ■ Hypotonic solution—less concentrated than intracellular fluid, it results in excess fluid entering the cell and may cause the cell to rupture ■ Hypertonic solution—more concentrated than intracellular fluid, it draws fluid away from the cell and causes the cell to shrink

21. Overview, cont’d. Homeostasis Homeostasis = equilibrium or health of the body as measured by established norms for blood pressure, heart rate, temperature, respiratory rate, and other indicators.

22. Body Composition Cells ■ Cell (plasma) membrane—thin outermost layer of the cell; regulates what enters and leaves the cell ■ Cytoplasm—colloidal substance (protoplasm) found in the cell; holds other structures in place ■ Nuclear membrane—thin layer surrounding the nucleus ■ Nucleus—located in the center of the cell; controls cell activity and contains genetic material (DNA) ■ Nucleolus—small structure(s) in nucleus; holds ribonucleic acid (RNA) and ribosomes essential for protein formation ■ Centriole—rod-shaped material in the cytoplasm that begins cell division ■ Cilia (singular cilium)—hairlike processes on the cell surface that move foreign particles along the cell surface ■ Flagella (singular flagellum)—whiplike processes on the cell surface; accommodate cell movement

23. Body Composition, cont’d. Figure 6-5. Basic animal cell with select structures.

24. Body Composition, cont’d. Cell Division Cell division occurs when one cell splits into two identical cells. The process is as follows: ■Interphase—DNA duplicates and chromosomes double ■ Mitosis—also referred to as cell division; comprises four phases: • Prophase—centrioles move to opposite ends of the cell, forming two poles; they stretch filaments between them, resembling longitudes on a globe • Metaphase—chromosomes line up along an equator-type line along centriole filaments • Anaphase—duplicated chromosomes separate, and one of each begins to move toward the opposite centriole or pole • Telophase—nucleus divides in the center, forming two distinct cells

25. Body Composition, cont’d. Cellular Movement of Substances The maintenance of homeostasis and fluid balance and the process of metabolism require constant movement of nutrients into the cell and the elimination of waste products from the cell: ■Movement without cellular energy • Diffusion—movement of molecules from area of higher to lower concentration • Osmosis—water diffusion (movement from area of higher to lower concentration) through a semipermeable membrane • Filtration—process of pushing water with dissolved materials through one side of a membrane; an example is kidney filtration

26. Body Composition, cont’d. ■ Movement with cellular energy • Active transport—movement of molecules from area of lower to higher concentration • Phagocytosis—ingestion and digestion of bacteria and other substances by phagocytic cells

27. Body Composition, cont’d. Tissues The body contains different types of tissues found in the diverse organs and systems. The study of tissue is called histology. ■Epithelial tissue—forms the outer surface of the body; lines body cavities and major tubes and passageways that open to the exterior • Cells—squamous (flat and irregular), cuboidal (square), or columnar (long and narrow) • Layers—simple (one layer) or stratified (more than one layer)

28. Body Composition, cont’d. ■ Connective tissue—supports and connects other tissues and structures • Soft—areolar, adipose • Fibrous—tendons, ligaments, capsules, fascia • Hard—cartilage, bone • Liquid—blood, lymph ■ Muscle tissue—produces movement • Skeletal muscle—moves muscle and bone (voluntary) • Cardiac muscle—forms the heart (involuntary) • Smooth muscle—forms visceral organs (involuntary) ■ Nerve tissue—composed of neurons (nerve cells); provides networks to carry impulses

29. Body Composition, cont’d. Membranes Membranes = thin sheets of tissue that line and protect body structures. Epithelial Membranes ■Serous membranes—secrete watery fluid • Parietal membranes—line body cavities • Visceral membranes—cover internal organs (pleura and pericardium are examples) ■ Mucous membranes—secrete mucus and line tubes or spaces open to the exterior ■ Cutaneous membrane—the skin

30. Body Composition, cont’d. Connective Tissue Membranes ■Synovial membranes—line joint cavities ■ Meninges—surround the brain and spinal cord and are composed of three layers ■ Fascia membranes—separate or bind muscles and permit movement of the skin ■ Other connective tissue membranes: • Pericardium—surrounds heart • Periosteum—surrounds bone • Perichondrium—surrounds cartilage

31. Body Systems Integumentary System Integumentary comes from the Greek word integument, meaning “cover.” The integumentary system is the largest system in the body. Functions of the Integumentary System ■Protects against infection and other “invaders” (e.g., radiation) ■ Assists with prevention of dehydration ■ Controls body temperature ■ Receives sensory information ■ Eliminates waste products ■ Produces vitamin D

32. Body Systems, cont’d. Components of the Integumentary System ■Skin—the largest organ; external covering of the body • Epidermis—the surface layer of the skin that contains strata (sublayers), melanin (pigment giving the skin its color), and keratin (protein that thickens skin and makes skin waterproof) • Dermis—the deeper layer of the skin that contains nerves, blood vessels, collagen, and other skin structures or appendages. Collagen is a fibrous protein found in the dermis, connective tissues, tendons, and ligaments. It is sometimes referred to as the body’s glue, providing strength and flexibility.

33. Body Systems, cont’d. ■ Appendages—structures located in the dermis that perform special functions • Sweat glands—coiled tubes located in the dermis that produce and transport sweat to help regulate body temperature and remove waste • Ceruminous glands—structures located in the ear that secrete cerumen (earwax) for protection • Sebaceous glands—structures connected to hair follicles located in the dermis that secrete sebum to lubricate skin and hair • Hair—structures composed primarily of dead keratinized tissue that cover most of body • Nails—hard, keratinized structures located on tips of fingers and toes • Subcutaneous tissue—layer of tissue below the dermis composed of adipose and elastic fibers that connects the dermis to muscle surfaces

34. Body Systems, cont’d. Figure 6-6. Cross section of skin.

35. Body Systems, cont’d. Common Diseases and Disorders of the Integumentary System ■Burns—tissue damage from exposure to heat, chemicals, or electricity • First degree (superficial)—involves the epidermis; has a red appearance with minimal or no edema • Second degree (partial thickness)—involves the epidermis and part of dermis; has a blistered red appearance with edema • Third degree (full thickness)—involves epidermis, entire dermis, and often the underlying tissues; has a pale white or charred appearance with broken skin and edema

36. Body Systems, cont’d. ■ Carcinoma—skin cancer • Basal cell carcinoma—malignant disease of the basal cell layer of skin • Squamous cell carcinoma—malignant disease of the squamous cell layer of skin; more likely to metastasize than basal cell • Melanoma—highly malignant nevus (mole)

37. Body Systems, cont’d.

38. Body Systems, cont’d. Skeletal System The skeletal system is the framework of the body. The human skeleton is composed of 206 bones, cartilage, and ligaments. Functions of the Skeletal System ■Provides frame and strength to the body ■ Produces body movement ■ Provides protection for organs (e.g., the skull protects the brain) ■ Serves as storehouse for calcium (Ca2+) salts ■ Produces blood cells in the bone marrow

39. Body Systems, cont’d. Components of the Skeletal System ■Bone—hard connective tissue impregnated with a calcium substance (206 bones in the adult skeleton) ■ Cartilage—firm connective tissue found primarily in joints, thorax walls, larynx, airway passages, and ears ■ Ligaments—bands of fibrous connective tissue that connect the articulating ends of bones to facilitate or limit movement; do not confuse ligaments with tendons, which connect muscle to bone ■ Joints—areas where two or more bones come together or articulate, such as the knee, shoulder, and neck

40. Body Systems, cont’d.

41. Body Systems, cont’d. Organization of the Skeletal System The bones are divided into the axial segment and the appendicular segment.

42. Body Systems, cont’d. Figure 6-7. Human skeleton.

43. Body Systems, cont’d. Axial Skeleton The axial segment of the skeleton consists of the bones of the skull, spine, and chest. ■ Cranium—skull • Frontal—forehead • Parietal—sides and top • Temporal—lower sides • Mastoid process—lower portion of the temporal bone • Styloid process—projection inferior to the external ear • Zygomatic process—upper cheek • Occipital—base of the skull, contains the foramen magnum (the opening in the skull that connects the spinal cord to the brain) • Sphenoid—bat-shaped, lateral eye orbits • Ethmoid—bony area between the nasal cavity and the orbits

44. Body Systems, cont’d. Figure 6-8. Adult skull.

45. Body Systems, cont’d. ■ Facial—14 bones form the face • Nasal—two bones that form the bridge of the nose • Zygomatic—arch of the cheek • Mandible—lower jaw • Maxilla—upper jaw

46. Body Systems, cont’d. ■ Vertebral column (spine)—26 vertebrae (bones) that cover the spinal cord • Cervical vertebrae (7 vertebrae)—neck bones; the first is called the atlas (supports the head); the second is called the axis (pivot for the head) • Thoracic vertebrae (12 vertebrae)—chest; attaches to the posterior portion of ribs • Lumbar vertebrae (5 vertebrae)—small of back; heavier and larger than other vertebrae • Sacrum (1 vertebra)—posterior of bony pelvis located between the two hip bones • Coccyx (1 vertebra)—tailbone

47. Body Systems, cont’d. Figure 6-9. Adult vertebral column.

48. Body Systems, cont’d. ■ Thorax—rib cage • Ribs—12 pair of bones that make up the thorax; the bars of the cage • Sternum—breast bone that, with the ribs, protects the heart - Manubrium—top of the breast bone that joins with the clavicle and first ribs - Xiphoid process—small tip at the lower end of the sternum

49. Body Systems, cont’d. Appendicular Skeleton The appendicular skeleton consists of the bones of the upper and lower extremities and the girdles attaching them to the axial skeleton portion. ■ Shoulder girdle • Clavicle—collar bone, which joins the sternum at the anterior and the scapula laterally • Scapula—shoulder blade

50. Body Systems, cont’d. ■ Upper extremities—arms, hands, fingers, and thumbs • Humerus—upper arm (largest arm bone) • Radius—lateral bone of forearm (in anatomic position, thumb side) • Ulna—medial bone of forearm (in anatomic position) • Carpals—the four bones that make up the wrist • Metacarpals—the five bones of the palm of the hand • Phalanges—fingers (three bones each) and thumbs (two bones each)