Figure 1.1 The Study of Anatomy at Different Scales Relative size m to mm Relative size mm to m Relative size m to nm meters (m) millimeters (mm) micrometers (m) nanometers (nm) Size 1.7m 120mm 12mm .5mm 120m 10m 1–12m 2m 10–120nm 11nm 8–10nm 2nm 1nm .1nm Approximate Magnification (Reduction) Factor ( .15) ( .12) ( .6)  20  83  103  103  103  105  106  106  106  107  108 From actual to artwork on this page Human Body Fingertip (width) Large protozoan DNA (diameter) Human heart Human oocyte Red blood cell Mitochondrion Ribosomes Amino acids Bacteria Viruses Proteins Atoms Unaided human eye Compound light microscope Scanning electron microscope Transmission electron microscope 1

TYPES OF ANATOMY 1 Microscopic anatomy The study of structures that cannot be seen without magnification Cytology—study of cells Histology—study of tissues 2

TYPES OF ANATOMY 2 Macroscopic anatomy The study of structures that can be seen without magnification Surface anatomy: refers to the superficial anatomical markings Regional anatomy: refers to all structures in a specific area of the body, whether they are superficial or deep Systemic anatomy: The study of the organ systems of the body (digestive system, cardiovascular system, etc.) 3

Examines structural changes over time Embryology: TYPES OF ANATOMY 3 Developmental anatomy: Examines structural changes over time Embryology: The study of early developmental stages Comparative anatomy: Considers different types of animals Clinical anatomy: Focuses on pathological changes during illness 4

TYPES OF ANATOMY 4 Surgical anatomy: Radiographic anatomy: Studies anatomical landmarks important for surgical procedures Radiographic anatomy: The study of anatomical structures with the use of x-rays or ultrasound scans on an intact body Cross-sectional anatomy: The use of radiographic techniques (CT and MRI scans) to look at cross sections of the body 5

Figure 1.2 Comparative Anatomy Embryo Adult TYPES OF ANATOMY Salmon (bony fish) Somites segmental blocks forming muscles, vertebrae, etc. Skull surrounds brain in cranail cavity Vertebrae surround spinal cord in spinal cavity Dorsal, hollow nerve cord forming brain and spinal cord Notochord a stiffened rod below spinal cord, usually replaced by vertebrae Muscular tail extends beyond exit of digestive tract Chicken Digestive tract Skull Limb bud Somites Vertebrae Basic Vertebrate Body Plan Mouth Heart Anus Human Skull Somites Braincase of cartilage or bone surrounds the brain Pharyngeal (gill) arches may persist or be modified to form other structures in adult Ventral body cavity contains thoracic and abdominopelvic organs Vertebrae Limb buds All vertebrates share a basic pattern of anatomical organization that differs from that of other animals. The similarities between vertebrates are most apparent when comparing embryos at comparable stages of development. The similarities are less obvious when comparing adult vertebrates. 6