An Introduction to Studying the Human Body Classification

An Introduction to Studying the Human Body • Classification of Living Things • Humans and many other animals are vertebrates • Characterized by a segmented vertebral column • Common characteristics suggest the same path in evolution • Homeostasis • The goal of physiological regulation and the key to survival in a changing environment © 2012 Pearson Education, Inc.

1 -1 Anatomy and Physiology Directly Affect Your Life • Anatomy • Is the oldest medical science • 1600 B. C. • Physiology • Is the study of function • Biochemistry • Biology • Chemistry • Genetics © 2012 Pearson Education, Inc.

1 -3 Anatomy and Physiology • Anatomy • Describes the structures of the body • What they are made of • Where they are located • Associated structures • Physiology • Is the study of: • Functions of anatomical structures • Individual and cooperative functions © 2012 Pearson Education, Inc.

1 -4 Relationships between Anatomy and Physiology • Anatomy • Gross anatomy, or macroscopic anatomy, examines large, visible structures • Surface anatomy: exterior features • Regional anatomy: body areas • Systemic anatomy: organ systems • Developmental anatomy: from conception to death • Clinical anatomy: medical specialties © 2012 Pearson Education, Inc.

1 -4 Relationships between Anatomy and Physiology • Anatomy • Microscopic anatomy examines cells and molecules • Cytology: study of cells and their structures • cyt- = cell • Histology: study of tissues and their structures © 2012 Pearson Education, Inc.

1 -4 Relationships between Anatomy and Physiology • Cell physiology: processes within and between cells • Organ physiology: functions of specific organs • Systemic physiology: functions of an organ system • Pathological physiology: effects of diseases © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Chemical (or Molecular) Level • Atoms are the smallest chemical units • Molecules are a group of atoms working together • The Cellular Level • Cells are a group of atoms, molecules, and organelles working together • The Tissue Level • A tissue is a group of similar cells working together • The Organ Level • An organ is a group of different tissues working together © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ System Level • An organ system is a group of organs working together • Humans have 11 organ systems • The Organism Level • A human is an organism © 2012 Pearson Education, Inc.

Figure 1 -1 Levels of Organization Cellular Level Chemical and Molecular Levels Heart muscle

Figure 1 -1 Levels of Organization Organ Level Tissue Level Cardiac muscle tissue The

1 -5 Levels of Organization • The Organ Systems • Integumentary • Major Organs • Skin • Hair • Sweat glands • Nails • Functions • Protects against environmental hazards • Helps regulate body temperature • Provides sensory information © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ Systems • Skeletal • Major Organs • Bones • Cartilages • Associated ligaments • Bone marrow • Functions • Provides support and protection for other tissues • Stores calcium and other minerals • Forms blood cells © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ Systems • Muscular • Major Organs • Skeletal muscles and associated tendons • Functions • Provides movement • Provides protection and support for other tissues • Generates heat that maintains body temperature © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ Systems • Nervous • Major Organs • Brain • Spinal cord • Peripheral nerves • Sense organs • Functions • Directs immediate responses to stimuli • Coordinates or moderates activities of other organ systems • Provides and interprets sensory information about external conditions © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ Systems • Endocrine • Major Organs • Pituitary gland • Thyroid gland • Pancreas • Adrenal glands • Gonads • Endocrine tissues in other systems • Functions • Directs long-term changes in the activities of other organ systems • Adjusts metabolic activity and energy use by the body • Controls many structural and functional changes during development © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ Systems • Cardiovascular • Major Organs • Heart • Blood vessels • Functions • Distributes blood cells, water and dissolved materials including nutrients, waste products, oxygen, and carbon dioxide • Distributes heat and assists in control of body temperature © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ Systems • Lymphatic • Major Organs • Spleen • Thymus • Lymphatic vessels • Lymph nodes • Tonsils • Functions • Defends against infection and disease • Returns tissue fluids to the bloodstream © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ Systems • Respiratory • Major Organs

1 -5 Levels of Organization • The Organ Systems • Respiratory • Functions • Delivers air to alveoli (sites in lungs where gas exchange occurs) • Provides oxygen to bloodstream • Removes carbon dioxide from bloodstream • Produces sounds for communication © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ Systems • Digestive • Major Organs • Teeth • Tongue • Pharynx • Esophagus • Stomach • Small intestine • Large intestine • Liver • Gallbladder • Pancreas © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ Systems • Digestive • Functions • Processes and digests food • Absorbs and conserves water • Absorbs nutrients • Stores energy reserves © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ Systems • Urinary • Major Organs • Kidneys • Ureters • Urinary bladder • Urethra • Functions • Excretes waste products from the blood • Controls water balance by regulating volume of urine produced • Stores urine prior to voluntary elimination • Regulates blood ion concentrations and p. H © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ Systems • Male Reproductive • Major Organs • Testes • Epididymides • Ductus deferentia • Seminal vesicles • Prostate gland • Penis • Scrotum © 2012 Pearson Education, Inc.

1 -5 Levels of Organization • The Organ Systems • Male Reproductive • Functions

1 -5 Levels of Organization • The Organ Systems • Female Reproductive • Major

1 -5 Levels of Organization • The Organ Systems • Female Reproductive • Functions • Produces female sex cells (oocytes) and hormones • Supports developing embryo from conception to delivery • Provides milk to nourish newborn infant • Sexual intercourse © 2012 Pearson Education, Inc.

1 -6 Homeostasis • All body systems working together to maintain a stable internal environment • Systems respond to external and internal changes to function within a normal range (body temperature, fluid balance) © 2012 Pearson Education, Inc.

1 -6 Homeostasis • Mechanisms of Regulation • Autoregulation (intrinsic) • Automatic response in a cell, tissue, or organ to some environmental change • Extrinsic regulation • Responses controlled by nervous and endocrine systems © 2012 Pearson Education, Inc.

1 -6 Homeostasis • Receptor • Receives the stimulus • Control center • Processes

Figure 1 -2 The Control of Room Temperature RECEPTOR Normal condition disturbed Thermometer Information affects STIMULUS: Room temperature rises Normal room temperature RESPONSE: Room temperature drops Normal condition restored EFFECTOR Air conditioner turns on 20° 30° 40° Sends commands to In response to input from a receptor (a thermometer), a thermostat (the control center) triggers an effector response (either an air conditioner or a heater) that restores normal temperature. In this case, when room temperature rises above the set point, thermostat turns on the air conditioner, and the temperature returns to normal. © 2012 Pearson Education, Inc. Room temperature (°C) CONTROL CENTER (Thermostat) HOMEOSTASIS Air conditioner turns on turns off 22 Normal range Time With this regulatory system, room temperature fluctuates around the set point.

1 -7 Negative and Positive Feedback • The Role of Negative Feedback • The response of the effector negates the stimulus • Body is brought back into homeostasis • Normal range is achieved © 2012 Pearson Education, Inc.

Figure 1 -3 Negative Feedback in the Control of Body Temperature RECEPTORS Temperature sensors in skin and hypothalamus Normal temperature disturbed Information affects CONTROL CENTER STIMULUS: Body temperature rises HOMEOSTASIS RESPONSE: Increased heat loss, body temperature drops Normal temperature restored EFFECTORS • Sweat glands in skin increase secretion • Blood vessels in skin dilate Sends commands to Events in the regulation of body temperature, which are comparable to those shown in Figure 1 2. A control center in the brain (the hypothalamus) functions as a thermostat with a set point of 37°C. If body temperature exceeds 37. 2°C, heat loss is increased through enhanced blood flow to the skin and increased sweating. © 2012 Pearson Education, Inc. Body temperature (°C) Thermoregulatory center in brain Normal body temperature 37. 2 37 36. 7 Vessels dilate, constrict, sweating increases decreases Normal range Time The thermoregulatory center keeps body temperature fluctuating within an acceptable range, usually between 36. 7 and 37. 2°C.

1 -7 Negative and Positive Feedback • The Role of Positive Feedback • The response of the effector increases change of the stimulus • Body is moved away from homeostasis • Normal range is lost • Used to speed up processes © 2012 Pearson Education, Inc.

Figure 1 -4 Positive Feedback: Blood Clotting accelerates Positive feedback loop Chemicals Damage to cells in the blood vessel wall releases chemicals that begin the process of blood clotting. © 2012 Pearson Education, Inc. The chemicals start chain reactions in which cells, cell fragments, and soluble proteins in the blood begin to form a clot. As clotting continues, each step releases chemicals that further accelerate the process. Blood clot This escalating process is a positive feedback loop that ends with the formation of a blood clot, which patches the vessel wall and stops the bleeding.

1 -7 Negative and Positive Feedback • Systems Integration • Systems work together to maintain homeostasis • Homeostasis is a state of equilibrium • Opposing forces are in balance • Dynamic equilibrium — continual adaptation • Physiological systems work to restore balance • Failure results in disease or death © 2012 Pearson Education, Inc.

Table 1 -1 The Roles of Organ Systems in Homeostatic Regulation © 2012 Pearson

1 -8 Anatomical Terminology • Superficial Anatomy • Locating structures on or near the body surface • Anatomical Landmarks • Anatomical position: hands at sides, palms forward • Supine: lying down, face up • Prone: lying down, face down © 2012 Pearson Education, Inc.

1 -8 Anatomical Terminology • Superficial Anatomy • Anatomical Landmarks • References to palpable structures • Anatomical Regions • Body regions • Abdominopelvic quadrants • Abdominopelvic regions • Anatomical Directions • Reference terms based on subject © 2012 Pearson Education, Inc.

Figure 1 -5 a Anatomical Landmarks Frontal or forehead Cranial or skull Cephalic or head Otic or ear Buccal or cheek Facial or face Cervical or neck Oral or mouth Mental or chin Thoracic or thorax, chest Axillary or armpit Mammary or breast Brachial or arm Abdominal (abdomen) Umbilical or navel Antecubital or front of elbow Anterior view © 2012 Pearson Education, Inc. Nasal or nose Ocular, orbital or eye Trunk

Figure 1 -5 a Anatomical Landmarks Antebrachial or forearm Pelvic (pelvis) Trunk Carpal or wrist Palmar or palm Manual or hand Pollex Digits or thumb (phalanges) or fingers (digital or phalangeal) Patellar or kneecap Inguinal or groin Pubic (pubis) Femoral or thigh Crural or leg Tarsal or ankle Digits (phalanges) or toes (digital or phalangeal) Hallux or great toe © 2012 Pearson Education, Inc. Pedal or foot Anterior view

Figure 1 -5 b Anatomical Landmarks Cephalic or head Acromial or shoulder Dorsal or

Figure 1 -5 b Anatomical Landmarks Upper limb Lumbar or loin Gluteal or buttock Lower limb Popliteal or back of knee Sural or calf Calcaneal or heel of foot Plantar or sole of foot © 2012 Pearson Education, Inc. Posterior view

Figure 1 -6 a Abdominopelvic Quadrants and Regions Right Upper Quadrant (RUQ) Left Upper Quadrant (LUQ) Right Lower Quadrant (RLQ) Left Lower Quadrant (LLQ) Abdominopelvic quadrants. The four abdominopelvic quadrants are formed by two perpendicular lines that intersect at the navel. The terms for these quadrants, or their abbreviations, are most often used in clinical discussions. © 2012 Pearson Education, Inc.

Figure 1 -6 b Abdominopelvic Quadrants and Regions Right hypochondriac region Right lumbar region Right inguinal region Epigastric region Umbilical region Hypogastric (pubic) region Left hypochondriac region Left lumbar region Left inguinal region Abdominopelvic regions. The nine abdominopelvic regions provide more precise regional descriptions. © 2012 Pearson Education, Inc.

Figure 1 -6 c Abdominopelvic Quadrants and Regions Liver Gallbladder Stomach Spleen Large intestine Small intestine Appendix Urinary bladder Anatomical relationships. The relationship between the abdominopelvic quadrants and regions and the locations of the internal organs are shown here. © 2012 Pearson Education, Inc.

Figure 1 -7 Directional References Superior Cranial Right Left Proximal Anterior or ventral Posterior or dorsal Lateral Caudal Medial Proximal Distal Inferior A lateral view. © 2012 Pearson Education, Inc. Distal An anterior view. Arrows indicate important directional terms used in this text; definitions and descriptions are given in Table 1 2.

Table 1 -2 Directional Terms © 2012 Pearson Education, Inc.

1 -8 Anatomical Terminology • Sectional Anatomy • Planes and sections • Plane: a three-dimensional axis • Section: a slice parallel to a plane • Used to visualize internal organization and structure • Important in radiological techniques • MRI • PET • CT © 2012 Pearson Education, Inc.

Figure 1 -8 Sectional Planes Frontal plane Sagittal plane Transverse plane © 2012 Pearson

Table 1 -3 Terms That Indicate Sectional Planes © 2012 Pearson Education, Inc.

1 -9 Body Cavities • Essential Functions of Body Cavities 1. Protect organs from accidental shocks 2. Permit changes in size and shape of internal organs • Ventral body cavity (coelom) • Divided by the diaphragm • Thoracic cavity • Abdominopelvic cavity © 2012 Pearson Education, Inc.

Figure 1 -9 Relationships among the Subdivisions of the Ventral Body Cavity • Provides protection • Allows organ movement • Linings prevent friction Subdivides during development into Abdominopelvic Cavity Thoracic Cavity Surrounded by chest wall and diaphragm Peritoneal Cavity Right Pleural Cavity Mediastinum Left Pleural Cavity Surrounds right lung Contains the trachea, esophagus, and major vessels Surrounds left lung Pericardial Cavity Surrounds heart © 2012 Pearson Education, Inc. Extends throughout abdominal cavity and into superior portion of pelvic cavity Abdominal Cavity Pelvic Cavity Contains many digestive glands and organs Contains urinary bladder, reproductive organs, last portion of digestive tract

1 -9 Body Cavities • Serous Membranes • Line body cavities and cover organs • Consist of parietal layer and visceral layer • Parietal layer — lines cavity • Visceral layer — covers organ © 2012 Pearson Education, Inc.

1 -9 Body Cavities • The Thoracic Cavity • Right and left pleural cavities • Contain right and left lungs • Mediastinum • Upper portion filled with blood vessels, trachea, esophagus, and thymus • Lower portion contains pericardial cavity • The heart is located within the pericardial cavity © 2012 Pearson Education, Inc.

Figure 1 -10 a The Ventral Body Cavity and Its Subdivisions POSTERIOR ANTERIOR Pleural cavity Thoracic cavity Pericardial cavity Diaphragm Peritoneal cavity Abdominal cavity Pelvic cavity © 2012 Pearson Education, Inc. Abdominopelvic cavity

Figure 1 -10 b The Ventral Body Cavity and Its Subdivisions Visceral pericardium Heart

Figure 1 -10 c The Ventral Body Cavity and Its Subdivisions ANTERIOR Pericardial cavity Pleural cavity Parietal pleura Right lung Left lung Mediastinum Spinal cord POSTERIOR © 2012 Pearson Education, Inc.

1 -9 Body Cavities • The Abdominopelvic Cavity • Peritoneal cavity: chamber within abdominopelvic cavity • Parietal peritoneum: lines the internal body wall • Visceral peritoneum: covers the organs © 2012 Pearson Education, Inc.

1 -9 Body Cavities • The Abdominopelvic Cavity • Abdominal cavity — superior portion • Diaphragm to top of pelvic bones • Contains digestive organs • Retroperitoneal space • Area posterior to peritoneum and anterior to muscular body wall • Contains pancreas, kidneys, ureters, and parts of the digestive tract © 2012 Pearson Education, Inc.