The human body in health and disease Medical Terminology Unit 2

Objectives Differentiate between anatomy and physiology Recognize and apply the anatomic reference systems to identify anatomic position, body planes, directions, regions and cavities Identify the major organ systems, organs and functions of each. Recognize spell, define and pronounce terms related to cells and genetics Recognize, spell, define and pronounce terms related to tissues and glands Recognize, spell, define and pronounce the terms used to describe disease and pathology

Anatomy and physiology Anatomy is the study of the structures of the body or “the parts.” Physiology is the study of the functions of the structures of the body or “how it works.” Homeostasis: maintaining a constant internal Environment.

The anatomic position This is our standard frame of reference when describing the body. This standard position can be described as: Standing up straight so the body is erect and facing forward Holding the arms at the sides with the hands turned with the palms facing forward.

Anatomic reference systems …are used to describe the locations of the stuctural units of the body. There are several ways to describe the location of body parts: Body Planes Body Directions Body Cavities

Body Planes Imaginary lines used to divide the body into sections for descriptive purposes. The planes are in reference to anatomic position Vertical planes (up and down) Midsagittal (also known as midline) divides the body into equal left and right halves Sagittal plane is a vertical line that divides the body into unequal left and right portions Frontal plane (also known as coronal plane) divides the body into front (anterior) and back (posterior) portions.

Horizontal Plane (side to side plane) Transverse plane divides the body into upper (superior) and lower (inferior) portions. It can be at waist-level or any other level across the body.

Body Directional terms Opposite Directional Term Ventral: front or belly side Dorsal: back of the body or organ Anterior: situated in front Posterior: situated in the back Superior: upper most, above, toward the head Inferior: lowermost, below or toward the feet Cephalic: toward to the head Caudal: toward the lower part of the body or tail Proximal: situated nearest the midline or beginning of a body structure (usually compares structures on upper or lower limbs) Distal: Situated farthest from the midline or beginning of a body structure (usually compares structures on upper or lower limbs) Medial: The direction toward or nearer the midline. Lateral: Direction toward or nearer the side and away from the midline Bilateral: relating to, or having, both sides

Body planes and directions

Major body cavities

A body cavity is a space within the body that contains and protects internal organs. Review the diagram in the previous slide and on p. 23 in your textbook. Can you name one organ found in each cavity?

Abdominal regions Umbilical: region surrounding the navel or belly button (umbilicus) Lumbar: even with the low back or lumbar spine Hypochondriac: “below the cartilage (or rib cartilage) Iliac: in the area of the ilium (one of the pelvic bones) NOTICE THE RIGHT AND LEFT SIDES OF THE FIGURE ON THIS SLIDE. Right and left are always in reference to the patient. When determining which side of the body you are on, remember to label the patient’s right and left, not yours. On a diagram, the patient will usually be supine, or face up (in anatomical position). Be very careful about correctly labeling right and left.

Abdominal quadrants Describing where an organ or pain is located can be easier if the area is divided in to quadrants (quad means 4). Take note again of the right and left sides of the patient. The abbreviations for these quadrants are commonly used.

Peritoneum (periton/o) The peritoneum is the membrane that protects and supports the organs located in the abdominal cavity (suspends the organs in place) The parietal peritoneum is the outer layer of this membrane The visceral peritoneum is the inner layer that surrounds the organs The mesentery is a layer of the peritoneum that suspends part of the intesine Retroperitoneal means located behind this membrane (retro- is a prefix that means behind) What term means inflammation of the peritoneum? Peritonitis

Ascites: an abnormal accumulation of clear or milky fluid in the peritoneal cavity. Laparoscopy: the visual examination of the interior of the abdomen with the use of a laparoscope.

The cell (cyt/o) Cytology is the study of the formation, structure, and function of cells (the basic units of the body) Three major parts of the cell are the cell membrane, nucleus and cytoplasm Chromosomes: each cell nucleus has 46 (23 pairs) of these genetic building blocks. 22 pairs are identical. The 23rd pair determines the sex of the child XX (female) or XY(male) Gametes or sex cells are the only cells that do not have 46 chromosomes. Each gamete has 23 chromosomes. When the ovum and the sperm meet, half of the chromosomes come from each parent. DNA: two long, coiled molecules that make up chromosomes. It is an acronym for deoxyribonucleic acid. Genes: the functional units of heredity

Genetics Genetics is the study of heredity Geneticist is a specialist in genetics Genetic disorders: hereditary diseases or condition that can be transmitted from the parents (the condition or disease can become evident at any time during the person’s life. Congenital Disorders: an abnormal condition that exists at the time of birth (not part of the genetic material). Can be caused by: Developmental disorder Prenatal influences Birth injuries Please see pp. 26 and 27 in your textbook for further information and examples.

Tissues (hist/o) Tissues are groups of similar cells that join together to perform a specific function. The four main types of tissue are: Epithelial tissue Connective tissue Muscle tissue Nerve tissue Please see p 27 in your textbook for clarification

Histologist is a specialist in tissues Histology is the study of the structure, composition and function of tissues Histologist is a specialist in tissues Stem cells are precursor cells with the ability to divide without limit and specialize. Tissue formation pathology Aplasia: lack of development Hypoplasia: incomplete development Hyperplasia: abnormal increase in the number of normal cells in normal arrangement Dysplasia: abnormal development or growth Anaplasia: change in the structure of cells and in their orientation to one another (as in malignancy or cancer)

Glands (aden/o) Glands are specialized group of epithelial cells that form secretions Endocrine glands secrete hormones directly into the blood stream Exocrine glands secrete into ducts (or outside the blood stream)

Organs and organ systems

Pathology (study of disease) Etiology is the study of the causes of disease Communicable disease is contagious Contaminated means the possible presence of an infectious agent. Bloodborne transmission is passing infectious agents via bodily fluids Sexually Transmitted Diseases (STD’s or venereal diseases) are passes via sexual contact Airborne Transmission occurs via infectious agents transmitted through the air. Foodborne or waterborne transmission is caused by eating or drinking contaminated food or water. Epidemiologist specializes in the study of the outbreak of disease Endemic refers to an ongoing presence of disease within a population group (i.e. the common cold) Epidemic is a sudden and widespread outbreak of a disease within a population group Pandemic refers to an outbreak of a disease over a large geographic area

Types of diseases An infectious disease is caused by a pathogen An idiopathic disorder is an illness without a known cause Organic disorders exhibit physical changes that explain the symptoms being described by the patient Functional disorders have no physical changes to explain the symptoms Iatrogenic illnesses are due to a side effect or unfavorable response to a medical treatment A nosocomial infection is acquired in the hospital but was not present when the patient was admitted to the hospital.