��General Anatomy�Introduction���

Chapter 1

DEFINITION OF ANATOMY

• Anatomy
• Greek=to cut up, or dissect
• The science that deals with the structure of the body
• Kinds:
• Gross Anatomy
• Microscopic Anatomy
• Developmental Anatomy
• Comparative Anatomy

Gross Anatomy

• Definition:
• Study of structures with the naked eye.
• Kinds:
• Regional:
• body studied by region.
• Systemic:
• body studied by system.

Microscopic Anatomy

• Definition:
• Study of structures under the microscope.
• Kinds:
• Cytology:
• The study of cells.
• Histology:
• The study of tissues.
• Organology:
• The study of organs.

Developmental Anatomy

• Definition:
• The study of anatomical changes in a life cycle.
• Kinds:
• Embryology:
• The study of prenatal development (before birth).
• Postnatal development:
• The study of structures after birth.

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Comparative Anatomy

• Definition:
• Comparison of structures between organisms.
• Kinds:
• Vertebrate:
• Comparison of structures among the vertebrate classes.

Physiology

• The science that studies the function of body structures.
• Structure and function can not be completely separated.
• Form is related to function

STRUCTURAL LEVELS OF ORGANIZATION

1. The atom [i.e. Carbon (C), Hydrogen (H), or Oxygen(O)]. An atom is defined as the smallest particle of an element. Atoms combine with (react with) other atoms to form…
2. molecules [i.e. carbon dioxide (CO2), water (H20)]. A molecule is defined as a particle composed of 2 or more joined atoms. Molecules combine with other molecules to form…
3. macromolecules (i.e. carbohydrates, lipids, proteins, nucleic acids). A macromolecule is defined as a large molecule. Macromolecules combine with other macromolecules to form…
4. organelles (i.e. cell membrane, nucleus, ribosomes). An organelle is defined as a small organ of a cell, which performs a particular function. Organelles collectively compose ...

STRUCTURAL LEVELS OF ORGANIZATION

E. cells: The cell is defined as the basic unit of structure and function of living organisms!

Each cell has a set of organelles and performs a particular function (i.e. a red blood cell has a biconcave shape and is anucleate. This structure increases its surface area, allowing for the transport of more oxygen.

Some cells have all of the machinery that they need to live.

Similar cells are arranged into...

F. tissues (i.e. epithelia, connective, muscle, nervous). A tissue is defined as a group of similar cells that performs a specialized function. Two or more tissues combine to form...

STRUCTURAL LEVELS OF ORGANIZATION

G. organs (i.e. skin, heart, brain). An organ is defined as a structure consisting of a group of tissues that performs a specialized function. Two or more organs combine to form...

H. systems (i.e. integumentary, cardiovascular, ….). A system is defined as a group of organs that act together to carry on a specialized function. There are 11 organ systems that collectively form the...

I. human organism An organism is the most complex level of organization and is defined as an individual living thing.

J. The levels of hierarchy could be further extended to include; populations, communities, ecosystems, and the biosphere.

Body Systems

Integumentary System

• Components
• Skin
• Skin appendages: Hair, nails, sweat & sebaceous glands.
• Functions
• External covering
• Protection
• Synthesis of vitamin D
• Location of sense receptors

Skeletal System

• Components
• Bones
• Joints and adjacent cartilages
• Functions
• Support
• Protection
• Movement
• Blood cell production (red bone marrow)
• Mineral storage (calcium and phosphorus)

Muscular System

• Components
• Skeletal Muscles
• Associated Connective Tissues (tendons)
• Functions
• Locomotion
• Manipulation of the environment
• Facial expression (communication)
• Maintain posture
• Produce heat

Circulatory System

• Components
• Cardiovascular System
• Lymphatic System
• Function
• Transportation of materials within the body.
• To and from internal and external environments.

Cardiovascular System

• Components
• Heart
• Blood Vessels
• Functions
• Transportation of blood.
• Blood contains O₂ and CO_2, nutrients, wastes, etc.
• Blood is composed of plasma and cells.

Lymphatic System

• Components
• Lymphatic Organs (spleen, lymph nodes, thymus, etc.).
• Lymphatic Vessels.
• Functions
• Transportation of lymph.
• Lymph is derived from tissue fluid.
• Houses white blood cells.

Immune System

• Components
• Immune organs (bone marrow, thymus, etc.)
• White blood cells (lymphocytes, macrophages, etc.)
• Function
• Defense (Immune response).

Nervous System

• Components
• Central Nervous System (CNS): Brain & Spinal cord.
• Peripheral Nervous System (PNS): Nerves, sense receptors
• Functions
• Control system (fast, “hard wired”)
• Response to external and internal environments

Endocrine System

• Components
• Glands that secrete hormones.
• E.g., pituitary, pancreas, thyroid, …..
• Functions
• Control system (slow, “chemical”)
• Regulates processes such as growth, reproduction and nutrient use.

Respiratory System

• Components
• Lungs
• Tubing ( trachea, bronchus, etc.)
• Larynx (vocal cords)
• Functions
• Exchange of respiratory gases (O₂ and CO₂) between blood and atmosphere.
• Voice production.

Digestive System

• Components
• Alimentary canal (mouth, pharynx, esophagus, stomach, small intestine & large intestine)
• Accessory organs (liver, salivary glands & pancreas)
• Functions
• Break down of food into small, absorbable pieces.
• Absorption of nutrients into blood.
• Eliminate waste products.

Urinary System

• Components
• Kidneys, Ureters, Urinary bladder, Urethra
• Functions
• Eliminate waste (nitrogen) from blood.
• Between blood and external environment.
• Regulates water, electrolytes, acid/base balance.

Reproductive System

• Components
• Male Reproductive System
• Female Reproductive System
• Functions
• Perpetuation of the species.
• Hormones influence structure and function.
• Sexually dimorphic species.

Anatomical�Terminology

• Anatomic position is a specific body position in which an individual stands upright with the feet parallel and flat on the floor.
• The head is level, and the eyes look forward toward the observer.
• The arms are at either side of the body with the palms facing forward and the thumbs pointing away from the body.

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Anatomical Terminology

• A plane is an imaginary surface that slices the body into specific sections.
• The three major anatomic planes of reference are the coronal, transverse, and sagittal planes.

Sections�and Planes

A coronal plane, also called a frontal plane, is a vertical plane that divides the body into anterior (front) and posterior (back) parts.

Sections�and Planes

• A transverse plane, also called a cross-sectional plane or horizontal plane, cuts perpendicularly along the long axis of the body or organ separating it into both superior (upper) and inferior (lower) parts.

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Sections�and Planes

• A sagittal plane or median plane, extends through the body or organ vertically and divides the structure into right and left halves.

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Sections and Planes

• A sagittal plane that passes in the body midline is called midsagittal plane.
• A plane that is parallel to the midsagittal plane, but either to the left or the right of it, is termed a parasagittal (or sagittal) plane.
• A minor plane, called the oblique plane, passes through the specimen at an angle.

Directional Terms of the Body

• Directional terms are precise and brief, and for most of them there is a correlative term that means just the opposite.

Relative and Directional Terms of the Body

• Relative to front (belly side) or back (back side) of the body:
• Anterior = In front of; toward the front surface
• Posterior = In back of; toward the back surface
• Dorsal =At the back side of the human body
• Ventral = At the belly side of the human body

Relative and Directional Terms of the Body

• Relative to the head or tail of the body:
• Superior = Toward the head or above.
• Inferior = Toward feet not head.
• Caudal = At the rear or tail end.
• Cranial = At the head end.

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Relative and Directional Terms of the Body

• Relative to the midline or center of the body:
• Medial = Toward the midline of the body
• Lateral = Away from the midline of the body
• Deep = On the inside, underneath another structure
• Superficial = On the outside

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Relative and Directional Terms of the Body

• Relative to point of attachment of the appendage:
• Proximal = Closest to point of attachment to trunk
• Distal = Furthest from point of attachment to trunk

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ORGANIZATION OF THE HUMAN BODY

Human Body

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Axial Portion Appendicular Portion

Head Upper Limbs

Neck Lower Limbs

Trunk

- Thorax

- Abdomen

- Pelvis

Axial Portion

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DORSAL CAVITY VENTRAL CAVITY

1. CRANIAL CAVITY 1. THORACIC CAVITY

brain lungs

mediastinum

2. VERTEBRAL CANAL thymus

spinal cord heart

esophagus

trachea

2. ABDOMINOPELVIC CAVITY

ABDOMINAL CAVITY PELVIC CAVITY stomach urinary bladder liver internal reproductive spleen organs

gallbladder

small intestine

large intestine

• Note that the diaphragm muscle separates the thoracic from abdomino-pelvic cavities.
• Note that the kidneys, adrenal glands, pancreas, and ureters are behind the abdominopelvic cavity. This is referred to as retroperitoneal.

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• Membrane:
• a soft, thin, pliable layer of tissue that either:
• covers a vital (visceral organ) =

Visceral Membrane

• lines a body cavity =

Parietal Membrane

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• There is a space between a visceral and parietal membrane into which serous fluid is secreted for lubrication.

Thoracic and Abdominopelvic Membranes

• There are specific names for the membranes around the heart, lungs, and abdominal organs:

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• Serous Membranes of the Lungs:
• The membrane on the surface of the lung is called
• visceral pleura.

• The membrane that lines the cavity in which the lungs are located is called
• parietal pleura.

• The space between these two membranes is called
• pleural cavity
• it is filled with serous fluid.

• Serous Membranes of the Heart:
• The membrane on the surface of the heart is called:
• visceral pericardium.
• The membrane that lines the cavity in which the heart is located is called:
• parietal pericardium.
• The space between these two membranes is called:
• pericardial cavity
• it is filled with serous fluid.

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• Serous Membranes of the Abdominal Organs:
• The membrane on the surface of the liver, stomach, etc. is called:

visceral peritoneum.

• The membrane that lines the abdominal cavity is called:

parietal peritoneum.

• The space between these two membranes is called the peritoneal cavity, and it is filled with serous fluid.

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Organization of the Body

Organization of the Body

Abdominal Divisions

• Quadrants: 4

(separated by the transumbilical and median planes):

• Right Upper Quadrant
• Right Lower Quadrant
• Left Upper Quadrant
• Left Lower Quadrant

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Abdominal Divisions

• Regions: 9

(separated by the 2 midclavicular lines vertically and the subcostal and intertubercular lines horizontally)

• Rt. Hypochondriac region.
• Rt. Lumbar region.
• Rt. Iliac (Inguinal) region.
• Epigastric region.
• Umbilical region.
• Hypogastric (Pubic) region.
• Lt. Hypochondriac region.
• Lt. Lumbar region.
• Lt. Iliac (Inguinal) region.

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