Anatomical Positions & Directional Terms PDF

Introduction Anatomical Positions & Directional Terms, Homeostasis Gerald S. Bernal, RMT, MD, FPCP, MSIM, FPSD Copyright © 2023 Gerald S. Bernal, MD Anatomy Describes the structures of the body: composition - what they a...

Introduction Anatomical Positions & Directional Terms, Homeostasis Gerald S. Bernal, RMT, MD, FPCP, MSIM, FPSD Copyright © 2023 Gerald S. Bernal, MD Anatomy Describes the structures of the body: composition - what they are made of location - where they are located association/ organization with other structures Physiology study the functions of anatomical structures, both as individual and group (cooperative) - how the specific organ operate (work) at the molecular or cellular level KEY CONCEPT Intimate relationship between anatomy and physiology since all physiological functions are performed by specific anatomical structures Principle of complementarity – “structure and function are complementary" Function always reflects structure What a structure can do depends on its specific form *Complementary- use of two things when each adds something to the other or helps make the other better  11 Organ systems to study  Integumentary  Skeletal ▪Lymphatic ▪Respiratory  Muscular ▪Digestive  Nervous ▪Urinary  Endocrine ▪Reproductive  Cardiovascular Integration- all organ systems work together to promote the well-being of the entire body  TIP: Key to learning anatomy is understanding function For example: Left side of heart is larger than right. Why is that?  ANATOMICAL POSITIONS AND DIRECTIONAL TERMS Gerald S. Bernal, RMT, MD, FPCP, MSIM STANDARD ANATOMICAL POSITION Anatomical Positions and Directional Terms SUPERIOR (cranial or cephalad)- toward head end or upper part of a structure or the body; above INFERIOR (caudal)- away from the head end or toward the lower part of a structure or the body; below ANTERIOR (ventral) - toward or at the front of the body; in front of POSTERIOR (dorsal)- toward or at the backside of the body; behind MEDIAL - toward or at midline of the body; on the inner side of LATERAL - away from the midline of the body; on the outer side of PROXIMAL - close to the origin of the body part or the point of attachment of a limb to the body trunk DISTAL - farther from the origins of a body part or the point of attachment of a limb to the body trunk SUPERFICIAL - toward or at the body surface DEEP - away from the body surface; more internal INTERMEDIATE - between a more medial and a more lateral structure REGIONAL TERMS  REGIONAL TERMS ANTERIOR BODY LANDMARKS abdominal - anterior body trunk below the ribs acromial - point of shoulder antecubital - anterior surface of elbow axillary - armpit brachial - arm buccal - cheek area carpal - wrist cervical - neck region  REGIONAL TERMS ANTERIOR BODY LANDMARKS coxal - hip crural - leg digital - fingers, toes femoral - thigh fibular - lateral part of leg inguinal - groin; area where thigh meets body trunk nasal - nose area oral - mouth area  REGIONAL TERMS ANTERIOR BODY LANDMARKS orbital - eye area patellar - anterior knee pelvic - area overlying the pelvis anteriorly pubic - genital region sternal - breastbone area tarsal - ankle region thoracic - chest umbilical - navel  REGIONAL TERMS POSTERIOR BODY LANDMARKS cephalic - head deltoid - curve of shoulder formed by deltoid muscle gluteal - buttock lumbar - area of back between ribs and hips occipital - posterior surface of head popliteal - posterior area of knee  REGIONAL TERMS POSTERIOR BODY LANDMARKS sacral - area between hips scapular - shoulder blade region sural - posterior surface of lower leg; calf vertebral - area of spine BODY CAVITIES  BODY CAVITIES VENTRAL BODY CAVITY - contains all structures within the chest and abdomen 1. Thoracic cavity - contents: lungs, heart, great vessels 2. Abdominopelvic cavity Abdominal: - contains stomach, liver, intestines, Pelvic: reproductive organs, bladder, rectum  BODY CAVITIES DORSAL BODY CAVITY 1. Cranial cavity - space inside the bony skull contents: brain, cranial nerves 2. Spinal cavity - extends from cranial cavity to the end of vertebral column contents: - spinal cord  Homeostasis definition/concept: ability of body to maintain a stable internal environment in relation to an ever-changing outside world necessary for the body to function normally and to sustain life all body systems work together to maintain the internal environment in stable normal range while reacting to external and internal changes (examples: body temperature, fluid balance) always changing to keep internal environment stable (dynamic state of equilibrium) homeostatic imbalance - failure to function within a normal range leads to disease Homeostatic Control Mechanisms 3 Input: Control Information center 4Output: sent along Information sent afferent along efferent pathway to pathway to Receptor (sensor) Effector 2Change detected by receptor 5Response of Im effector feeds 1 Stimulus: ba back to Produces l an ce influence change in variable magnitude of stimulus and Variable (in homeostasis) returns variable to homeostasis Im ba l an ce Figure 1.4  Response to stimulus Negative Feedback effector (organ) oppose the stimulus by either shutting off or reducing the intensity of the original stimulus most common way by which homeostasis is maintained in the body example: regulation of room temperature in a cold and warm environment  Positive Feedback effector (organ) increase or exaggerate the stimulus farther NOT a way to maintain homeostasis 2 normal occasions in the body –blood clotting and birth Homeostatic Imbalance Disturbance in the body’s normal equilibrium (homeostasis) happens when the negative feedback mechanism is overwhelmed, allowing the (destructive) positive feedback mechanisms to take over often used as the definition of “disease”