Chapter 1 The Human Body An Orientation An

Chapter 1: The Human Body: An Orientation

An Overview of Anatomy The study of the structure of the human body Physiology The study of body function *Please understand the difference between structure and function

An Overview of Anatomy Anatomical terminology Branches of anatomy Based on ancient Greek or Latin Provides standard nomenclature worldwide Gross anatomy Microscopic anatomy (histology) Surface anatomy – need to know what a normal body looks like to identify anomalies, locate veins for venipuncture, etc.

An Overview of Anatomy Other branches of anatomy Developmental anatomy-structural changes of aging Embryology – study of development of fetus Pathological anatomy (pathology)- study of disease Radiographic anatomy- study of anatomy using radiographic imagery, CT, MRI, PET, ultrasound **Why are there so many different imaging techniques? Please understand what each technique images Functional morphology Microscopic – anatomy of structures using various microscopic instruments. Histology – study of tissues

The Hierarchy of Structural Organization Chemical level – atoms form molecules Cellular level – cells and their functional subunits Tissue level – a group of cells performing a common function *Please think about the fact that our bodies are made of atoms, the same thing as rocks, plants, stars and comets! By understanding the nature of specific atomic structures, you will become aware of how chemistry provides the basis of living systems. Chemistry is a simple matter of balancing electromagnetic charges! You can move a piece of metal by bringing a magnet nearby…movement!

The Hierarchy of Structural Organization Organ level – a discrete structure made up of more than one tissue. e. g. the heart is made of muscle (obviously), connective tissue, nerves and epithelial tissue (valves) Organ system – organs working together for a common purpose Organismal level – the result of all simpler levels working in unison

The Hierarchy of Structural Organization Figure 1. 1

Systemic v. Regional Anatomy Systemic – study of anatomy by system Regional – study of anatomy by region Most students use a combination of regional and systemic study

Integumentary System Forms external body covering Protects deeper tissues from injury Synthesizes vitamin D Site of cutaneous receptors (pain, pressure, etc. ) and sweat and oil glands http: //www. youtube. com/watch? v=no_XRno. NGf. E

Skeletal System Protects and supports body organs Provides a framework for muscles Blood cells formed within bones Stores minerals http: //www. youtube. com/watch? v=vya 4 wp. S 2 fgk

Muscular System Allows manipulation of environment Locomotion Facial expression Maintains posture Produces heat http: //www. youtube. com/user/bigsmokes 62#p/a/u/ 1/Rs. WNyqn. HQ 2 I

Nervous System Fast-acting control system Responds to internal and external changes

Endocrine System The Endocrine system works as a regulatory messaging system similar to the nervous system Remember: cells are isolated! They don’t know what to do unless they are told what to do and either the nervous system or then endocrine system tells them what to do! Glands secrete hormones that regulate Growth Reproduction Nutrient use

Cardiovascular System Blood vessels transport blood Carries oxygen and carbon dioxide Also carries nutrients and wastes Heart pumps blood through blood vessels Blood vessels are merely the plumbing which brings water, gases and nutrients to the individual cells. It is similar to a city’s water system. The heart is the pump just like our residential water has a pump station so that we have water pressure! Again, the cells are (mostly) fixed and isolated and they rely on the intelligence of the monitoring systems of the body (the nervous system) to provide it’s needs.

Lymphatic System/Immunity Picks up fluid leaked from blood vessels Disposes of debris in the lymphatic system Houses white blood cells (lymphocytes) Mounts attack against foreign substances in the body The lymphatic system is a highly understudied system in the body. It is in fact one of the most important systems of the body! Without proper functioning of this system, we would die!

Lymphedema The lymphatic drainage of the leg is impaired and the fluid collects in the limb causing it to swell. The cells are improperly nourished and will become diseased.

Respiratory System Keeps blood supplied with oxygen Removes carbon dioxide Gas exchange occurs through walls of air sacs in the lungs This is a simple system to understand but it also functions in the acid-base balance of the physiology

Digestive System Breaks down food into absorbable units Indigestible foodstuffs eliminated as feces

Urinary System Eliminates nitrogenous wastes Regulates water, electrolyte, and acid-base balance The cells of our body (all 70 trillion of them!) require an exact environment to survive. The urinary system along with the lymphatic system provides this environment directly.

Why do we have body systems? What do they provide? Do we need all of them? How did they come about? What is homeostasis? How does each system contribute to homeostasis?

Male & Female Reproductive Systems Overall function is to produce offspring Testes produce sperm and male sex hormones Ovaries produce eggs and female sex hormones Mammary glands produce milk

Gross Anatomy – An Introduction Anatomical position – a common visual reference point Person stands erect with feet together and eyes forward Palms face anteriorly with the thumbs pointed away from the body Directional terminology – refers to the body in anatomical position Standardized terms of directions are paired terms

Gross Anatomy – An Introduction Figure 1. 3

Gross Anatomy – An Introduction Directional terms Regional terms – names of specific body areas Axial region – the main axis of the body Appendicular region – the limbs

Orientation and Directional Terms Table 1. 1 (1 of 3)

Orientation and Directional Terms Table 1. 1 (1 of 3)

Orientation and Directional Terms Table 1. 1 (2 of 3)

Orientation and Directional Terms May be used on exams! Table 1. 1 (3 of 3)

Regional Terms Figure 1. 4 a

Regional Terms Figure 1. 4 b

Body Planes and Sections Coronal (frontal) plane Lies vertically and divides body into anterior and posterior parts Median (midsagittal) plane Specific sagittal plane that lies vertically in the midline

Body Planes and Sections Transverse plane Runs horizontally and divides body into superior and inferior parts Figure 1. 5

Oblique Section Through the Trunk Figure 1. 6 Oblique Plane Divides the body at an angle between the horizontal and vertical planes

Banana Sectioned into Planes Figure 1. 7

The Human Body Plan Tube-within-a-tube Bilateral symmetry Dorsal hollow nerve cord Notochord (primative supporting rod) and vertebrae Segmentation Pharyngeal pouches (gills!) Post-anal tail (at some point in development) Characteristics common to all vertebrate

Basic Human Body Plan and Structures Shared with all Vertebrates Figure 1. 8 a

Basic Human Body Plan and Structures Shared with all Vertebrates May be used on exams! Figure 1. 8 b

Basic Human Body Plan and Structures Shared with all Vertebrates Figure 1. 8 c

Body Cavities and Membranes Dorsal body cavity Cranial cavity Vertebral cavity

Body Cavities and Membranes Ventral body cavity Thoracic cavity – divided into three parts Be able to describe it’s location and contents! Anterior-sternum, posterior-thoracic vertebrae, lateral-lungs, superior-1 st rib, inferior-diaphragm Two lateral parts each containing a lung surrounded by a pleural cavity Mediastinum – lies between the lungs and contains the heart surrounded by the pericardial sac, the trachea, the esophagus, the superior vena cava, the inferior vena cava and various nerves. This is an anatomically important area.

Body Cavities and Membranes Ventral cavity (continued) Abdominopelvic cavity – divided into two parts Abdominal cavity – contains the liver, stomach, kidneys, and other organs Pelvic cavity – contains the bladder, some reproductive organs, and rectum

Body Cavities and Membranes Figure 1. 9 a

Body Cavities and Membranes Figure 1. 9 b

Body Cavities and Membranes Serous cavities – a coelomic cavity, like that enclosed by the pericardium, peritoneum, or pleura, not communicating with the outside body, and whose lining membrane secretes a serous fluid. Pleura (enclosing lungs), pericardium(enclosing heart), and peritoneum(enclosing most of abdominal organs but specifically NOT the kidneys!) Parietal serosa – outer wall of the cavity Visceral serosa covers the visceral organs *Always remember the difference between parietal and visceral…visceral is ALWAYS against the organ(s)

Body Cavities and Membranes The purpose of the serosal membranes is to reduce friction so that viscera (organs) move freely and stay cool. Figure 1. 10 a, b

Body Cavities and Membranes Figure 1. 10 c

Body Cavities and Membranes Figure 1. 10 d

Body Cavities and Membranes Other cavities Oral cavity Nasal cavity Orbital cavities Middle ear cavities Synovial cavities

Other Body Cavities Figure 1. 11

Abdominal Regions and Quadrants Abdominal regions divide the abdomen into nine regions Abdominal quadrants divide the abdomen into four quadrants Right upper and left upper quadrants Right lower and left lower quadrants

Abdominal Regions Figure 1. 12 a, b

Abdominal Quadrants Figure 1. 12 c

Microscopic Anatomy Microscopy – examining small structures through a microscope Light microscopy illuminates tissue with a beam of light (lower magnification) Electron microscopy uses beams of electrons (higher magnification) TEM transmission electron microscopy will always be sharper than light microscope

Microscopic Anatomy Figure 1. 13

Microscopic Anatomy Preparing human tissue for microscopy Specimen is fixed (preserved) and sectioned Specimen is stained to distinguish anatomical structures Acidic stain – negatively charged dye molecules Basic stain – positively charged dye molecules

Microscopic Anatomy Scanning electron microscopy Heavy metal salt stain – deflects electrons in the beam to different extents Artifacts Minor distortions of preserved tissues Not exactly like living tissues and organs

Clinical Anatomy – An Introduction to Medical Imaging Techniques X ray – electromagnetic waves of very short length Best for visualizing bones and abnormal dense structures Figure 1. 14

Clinical Anatomy – An Introduction to Medical Imaging Techniques Variations of X ray Fluoroscope – images are viewed on a fluorescent screen Allows viewing of internal organs as they move Cineradiography – uses X-ray cinema film to record organ movements

Advanced X-Ray Techniques Computed (axial) tomography (CT or CAT) – takes successive X rays around a person's full circumference Translates recorded information into a detailed picture of the body section This technique receives information only from transverse planes and adds them up to form a 3 D image.

Advanced X-Ray Techniques Digital subtraction angiography (DSA) imaging provides an unobstructed view of small arteries DSA is often used to identify blockages of arteries that supply the heart or brain

Advanced X-Ray Techniques Positron emission tomography (PET) – forms images by detecting radioactive isotopes injected into the body Sonography (ultrasound imaging) – body is probed with pulses of high-frequency sound waves that echo off the body's tissues Imaging technique used to determine the age of a developing fetus

Advanced X-Ray Techniques Magnetic resonance imaging (MRI) – produces high-quality images of soft tissues Distinguishes body tissues based on relative water content Figure 1. 19 a