Chapter 1 Outline

I.        The Human Body: An Orientation

1.     An overview of Anatomy and Physiology

a.       Introduction

b.      Definitions

                                                              i.      Anatomy – study of the structure and shape of the body and it’s parts

                                                            ii.      Physiology – study of how the body and it’s parts work or function

c.       Topics of Anatomy

                                                              i.      Gross (large) or Macroscopic Anatomy

·         Large Structures

·         Easily Observable

·         Studied through dissection

                                                            ii.      Microscopic Anatomy

·         Very small structures

·         Can only be viewed with a microscope

·         Cytology – study of cells

·         Histology – study of tissues

d.      Topics of Physiology

                                                              i.      Renal – kidney functions

                                                            ii.      Cardiovascular – heart and blood vessel functions

                                                          iii.      Neural – nervous system functions

                                                           iv.      Other Organ System Physiology

                                                             v.      Close relationship between structure and function (the way something is built has everything to do with the way it can function)

e.      Complementarity of Structure and Function

2.    Levels of Structural Organization

a.       Levels of Structural Hierarchy (See Figure 1.1)

                                                              i.      Chemical Level

·         Atoms combine to form molecules

                                                            ii.      Cellular Level

·         Cells are made up of molecules

                                                          iii.      Tissue Level

·         Tissues consist of similar types of cells

                                                           iv.      Organ Level

·         Organs are made up of different types of tissues

                                                             v.      Organ System Level

·         Organ systems consist of different organs that work together closely

                                                           vi.      Organismal Level

·         Human organisms are made up of many organ systems

b.      Summary of the Body’s Organ System (See Figure 1.2)

                                                              i.      Integumentary System - skin

·         Forms the external body covering

·         Protects deeper tissue from injury

·         Helps regulate the body temperature

·         Location of cutaneous nerve receptors

                                                            ii.      Skeletal System

·         Protects and supports body organs

·         Provides muscle attachment for movement

·         Sit of blood cell formation

·         Stores minerals

                                                          iii.      Muscular System

·         Produces movement

·         Maintains posture

·         Produces heat

                                                           iv.      Nervous System

·         Fast-acting control system

·         Responds to internal and external change

·         Activates muscles and glands

                                                             v.      Endocrine System - hormones

·         Secretes regulatory hormones

·         Growth

·         Reproduction

·         Metabolism

                                                           vi.      Cardiovascular System

·         Transports materials in body via blood pumped by the heart

·         In comes Oxygen (good)

·         Out goes Carbon Dioxide (bad)

·         Nutrients

·         Wastes

                                                         vii.      Lymphatic System / Immune System

·         Returns fluids to blood vessels

·         Cleanses the blood

·         Involved in immunity

                                                       viii.      Respiratory System

·         Keeps blood supplied with oxygen

·         Removes carbon dioxide

                                                           ix.      Digestive System – oral cavity, esophagus, stomach, small intestine, large intestine, rectum, anus

·         Breaks down food

·         Allows for nutrient absorption into blood

·         Eliminate indigestible material

                                                             x.      Urinary System – kidney, ureter, urinary bladder, urethra

·         Eliminates nitrogenous wastes

·         Maintains acid-base balance

·         Regulates water and electrolytes

                                                           xi.      Reproductive System – (male) prostate gland, vas deferens, testis, scrotum, seminal vesicles, penis (female) mammary glands (in breasts). Uterine tube, ovary, uterus, vagina

·         Produces offspring

3.    Necessary Life Functions

a.       Maintain Boundaries

                                                              i.      Gradients = differences

b.      Movement

                                                              i.      Locomotion – organism moves

                                                            ii.      Movement of substances – within or outside

c.       Responsiveness: ability to sense changes and react

d.      Digestion: break-down and absorption of nutrients

e.      Metabolism: chemical reactions within the body

                                                              i.      Produces energy – from food

                                                            ii.      Makes body structures

f.        Excretion: eliminates waste from metabolic reactions

g.       Reproduction: produces future generation

h.      Growth: increases cell size and number of cells

4.    Homeostasis

a.       Maintenance of a stable internal environment

b.      A dynamic state of equilibrium

c.       Homeostasis is necessary for normal body functioning to sustain life

d.      Homeostatic imbalance

                                                              i.      A disturbance in homeostasis resulting in disease

e.      Homeostatic control mechanisms (See Figure 1.4)

                                                              i.      Elements of a control system

·         Receptor

·         Control Center

·         Effectore

                                                            ii.      Negative feedback mechanism (See Figure 1.5)

·         Includes most homeostatic control mechanisms

·         Shuts out the original stimulus, or reduces it’s intensity

·         Works like a household thermostat

·         Opposite directional change

·         Effector decreases original stimulus

                                                          iii.      Positive feedback mechanism (See Figure 1.6)

·         Increases the original stimulus to push the variable farther

·         In the body this only occurs in blood clotting and during the birth of a baby

·         Same directional change

·         Effector enhances original stimulus

5.    The Language of Anatomy

a.       Special terminology is used to prevent misunderstanding

b.      Exact terms are used for: position, direction, regions, and structures

c.       Anatomical position: a position used to be able to see all parts of the body

                                                              i.      Human body erect

                                                            ii.      Arms at sides

                                                          iii.      Palms forward

                                                           iv.      Feet together

d.      Directional Terms (See Table 1.1)

                                                              i.      Definition: Directional terms allow us to explain where one body structure is in relation to another

                                                            ii.      Superior – toward the head end or upper part of a structure or the body; above

·         The forehead is superior to the nose

                                                          iii.      Inferior*****************

                                                           iv.      Anterior (ventral) -  the front

·         The mouth is on the anterior of the body where as the shoulder blades are on the posterior side of the body

                                                             v.      Posterior (dorsal) – toward or at the backside of the body; behind

·         The heart is posterior to the breastbrone

                                                           vi.      Proximal – close to the origin of the body part or the point of attachment of a limb to the body trunk

·         The elbow is proximal to the wrist (meaning that the elbow is closer to the shoulder or attachment point of the arm than the wrist is)

                                                         vii.      Distal - farther from the origin of a body part or the point of attachment of a limb to the body trunk

·         The knee is distal to the thigh

                                                       viii.      Lateral – away from the midline of the body; on the outer side of

·         The arms are lateral to the chest

                                                           ix.      Intermediate/Medical

                                                             x.      Medial - toward or at the midline of the body; on the inner side of

·         The heart is medial to the arm

                                                           xi.      Superficial (external) – toward or at the body surface

·         The skin is superficial to the skeleton

                                                         xii.      Deep (internal) – away from the body surface; more internal

·         The lungs are deep to the rib cage

e.      Regional Terms (See Figure 1.7)

                                                              i.      Definition: Regional terms are used to designate specific areas within the major body divisions

·         Axial part = from head to pubic region

·         Appendicular part = arms and legs

                                                            ii.      Anterio

·         Nasal (Nose)

·         Oral (mouth)

·         Cervical (neck)

·         Axillary (armpit)

·         Frontal (forehead)

·         Orbital (eye)

·         Buccal (cheek)

·         Sternal (breastbone)

·         Thoracic (chest)

·         Mammary (breast)

·         Abdominal (abdomen)

·         Brachial (arm)

·         Umbilical (navel)

·         Pelvic (pelvis)

·         Femoral (thigh)

·         Carpal (wrist)

·         Digital (fingers)

·         Coxal (hip)

·         Pubic (genital region)

·         Patellar (anterior knee)

·         Pedal (foot)

                                                          iii.      Posterior Body Landmarks

·         Cephalic (head)

·         Otic (ear)

·         Sacral (between hips)

·         Occipital (base of the skull)

·         Vertebral (spinal column)

·         Scapular (shoulder blade)

·         Dorsal (back)

·         Gluteal (buttock)

·         Calcaneal (heel)

·         Plantar (sole)

·         Acromial (point of shoulder)

·         Popliteal (back of the knee)

f.        Body Planes (See Figure 1.8)

                                                              i.      Sagittal plane: A sagittal section divides the body or organ into left and right parts

·         Midsagittal – a median, or midsagittal, section divides the body (or organ into equal left and right parts (median plane)

·         Parasagittal – Nearby planes (next to the midsagittal plane)

                                                            ii.      Transverse Plane = horizontal plane

·         A transverse, or cross, section deivides the body (or organ) into superior and inferior parts

                                                          iii.      Oblique - doesn’t fit in the frontal, transverse, or sagittal plane

                                                           iv.      Frontal Plane - d frontal section divides the body (or organ) into anterior and posterior parts

g.       Body Cavities (See Figure 1.9)

                                                              i.      Dorsal Body Cavity

·         Cranial cavity – houses the brain

·         Vertebral cavity – spinal cavity (inside the vertebral cavity) houses the spinal cord

                                                            ii.      Ventral Body Cavity

·         Thoracic cavity – houses heart, lungs, and other

a.     Pleural cavities

b.    Pericardial Cavity

·         Abdominopelvic cavity – houses digestive system and most urinary system organs

a.     Abdominal Cavity

b.    Pelvic Cavity

h.      Membranes in the ventral body cavity (See Fig. 1.10)

                                                              i.      Serous membrane = serosa

·         Parietal serosa

·         Visceral serosa

                                                            ii.      Serous fluid

·         Location

·         Functions

                                                          iii.      Examples of serous membranes

·         Pericardium

·         Pleura

·         Peritoneum

i.        Quadrants