This document provides an overview of anatomy and physiology. It defines anatomy as the study of body structure and physiology as the study of body function. Anatomy can be studied regionally, systemically, or at the tissue, cellular, and molecular levels. Physiology considers how organ systems and individual organs function, often at the cellular or molecular level. Homeostasis and the interaction between structure and function are also discussed. Various anatomical planes, directions, and body cavities are defined.

2. Overview of Anatomy and Physiology
• AnatomyAnatomy – the study of the structure of
body parts and their relationships to one
another
– Gross or macroscopic
– Microscopic
– Developmental
• PhysiologyPhysiology – the study of the function of the
body’s structural machinery

3.  RegionalRegional – all structures in one part of the body
(such as the abdomen or leg)
 SystemicSystemic – gross anatomy of the body studied
by system
 SurfaceSurface – study of internal structures as they
relate to the overlying skin

4.  CytologyCytology – study of the cell
 HistologyHistology – study of tissues

5.  Traces structural changes throughout life
 EmbryologyEmbryology – study of developmental changes
of the body before birth

6.  Pathological anatomyPathological anatomy – study of structural
changes caused by disease
 Radiographic anatomyRadiographic anatomy – study of internal
structures visualized by X ray
 Molecular biologyMolecular biology – study of anatomical
structures at a sub-cellular level

7.  Considers the operation of specific organConsiders the operation of specific organ
systemssystems
◦ Renal – kidney function
◦ Neurophysiology – workings of the nervous system
◦ Cardiovascular – operation of the heart and blood
vessels
 Focuses on the functions of the body,Focuses on the functions of the body,
often at the cellular or molecular leveloften at the cellular or molecular level

8.  Understanding physiology also requires a
knowledge of physics, which explains electrical
currents, blood pressure, and the way muscle
uses bone for movement

9.  Function always reflects structure
 What a structure can do depends on its specific
form

10. Chemical level
Atoms combine to
form molecules
1
2
3
4
Cellular level
Cells are made up of molecules
Tissue level
Tissues consist of
similar types of
cells
5 Organ system level
Organ systems consist of different organs
that work together closely
Organ level
Organs are made up of
different types of tissues
6 Organismal level
The human organism is
made up of many organ
systems
Atoms
Molecules
Smooth muscle cell
Smooth
muscle
tissue
Connective
tissue
Smooth
muscle
tissue
Epithelial
tissue
Blood
vessel
(organ)
Heart
Blood
vessels
Cardiovascular
system
Figure 1.1

11.  ChemicalChemical – atoms combined to form molecules
 CellularCellular – cells are made of molecules
 TissueTissue – consists of similar types of cells
 OrganOrgan – made up of different types of tissues
 Organ systemOrgan system – consists of different organs that work
closely together
 OrganismalOrganismal – made up of the organ systems

12.  HomeostasisHomeostasis is the ability to maintain a
relatively stable internal environment in an ever-
changing outside world
 The internal environment of the body is in aa
dynamic state of equilibriumdynamic state of equilibrium
 Chemical, thermal, and neural factors interact to
maintain homeostasis

13.  Disturbance of homeostasis or the body’sDisturbance of homeostasis or the body’s
normal equilibriumnormal equilibrium
 Overwhelming of negative feedback mechanisms
allowing destructive positive feedback
mechanisms to take over

14.  Body erect
 Feet slightly apart
 Palms facing forward
 Thumbs point away from
body
Figure 1.7a

15.  Superior and inferiorSuperior and inferior – toward and away from
the head, respectively
 Anterior and posteriorAnterior and posterior – toward the front and
back of the body
 Medial, lateral, and intermediateMedial, lateral, and intermediate – toward
the midline, away from the midline, and between a
more medial and lateral structure

16.  Proximal and distalProximal and distal – closer to and farther from
the origin of the body
 Superficial and deepSuperficial and deep – toward and away from
the body surface

17. Table 1.1

18. Table 1.1

19.  AxialAxial – head,
neck, and trunk
 AppendicularAppendicular –
appendages or
limbs
 SpecificSpecific
regionalregional
terminologyterminology
Figure 1.7a

20. Figure 1.7b

21.  SagittalSagittal – divides the body into right and left
parts
 Midsagittal or medialMidsagittal or medial – sagittal plane that lies
on the midline
 Frontal or coronalFrontal or coronal – divides the body into
anterior and posterior parts
 Transverse or horizontalTransverse or horizontal (cross section) –
divides the body into superior and inferior parts
 Oblique sectionOblique section – cuts made diagonally

22.  The sagittal axis pierces the body from front to
back.
 The frontal axis passes from the right side to
the left.
 The vertical axis passes along the body of a
man having vertical position.
 The longitudinal axis as well passes along the
human body, but the poison of the man does not
matter; as well this axis passes along the limbs,
organs etc.
 NB: The axes do not divide the human

23. Figure 1.8

24.  Humans vary slightly in both external andHumans vary slightly in both external and
internal anatomyinternal anatomy
 Over 90% of all anatomical structures match
textbook descriptions, but:
◦ Nerves or blood vessels may be
somewhat out of place
◦ Small muscles may be missing
 Extreme anatomical variations areExtreme anatomical variations are
seldom seenseldom seen

25. Figure 1.9a

26.  Dorsal cavityDorsal cavity protects the nervous system, and is
divided into two subdivisions
◦ Cranial cavity is within the skull and encases
the brain
◦ Vertebral cavity runs within the vertebral
column and encases the spinal cord
 Ventral cavityVentral cavity houses the internal organs (viscera),
and is divided into two subdivisions: - Thoracic and
Abdominopelvic cavities

27. Figure 1.9b

28.  Thoracic cavityThoracic cavity is subdivided into pleural
cavities, the mediastinum, and the pericardial
cavity
◦ Pleural cavities – each houses a lung
◦ Mediastinum – contains the pericardial
cavity, and surrounds the remaining
thoracic organs
◦ Pericardial cavity – encloses the
heart

29.  The abdominopelvic cavity is separatedThe abdominopelvic cavity is separated
from the superior thoracic cavity by thefrom the superior thoracic cavity by the
dome-shaped diaphragmdome-shaped diaphragm
 It is composed of two subdivisions
◦ Abdominal cavity – contains the
stomach, intestines, spleen, liver, and
other organs
◦ Pelvic cavity – lies within the pelvis and
contains the bladder, reproductive
organs, and rectum

30.  Parietal serosaParietal serosa lines internal body walls
 Visceral serosaVisceral serosa covers the internal organs
 Serous fluid separates the serosae

31. Figure 1.10a

32. Figure 1.10b

33.  Oral and digestiveOral and digestive – mouth and cavities of the
digestive organs
 NasalNasal –located within and posterior to the nose
 OrbitalOrbital – house the eyes
 Middle earMiddle ear – contain bones (ossicles) that
transmit sound vibrations
 SynovialSynovial – joint cavities

34.  Umbilical
 Epigastric
 Hypogastric
 Right and left iliac or
inguinal
 Right and left lumbar
 Right and left
hypochondriac
Figure 1.11a

35. Figure 1.11b

36.  Right upper (RUQ)
 Left upper (LUQ)
 Right lower (RLQ)
 Left lower (LLQ)
Figure 1.12