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University of Sulaimani

College of Pharmacy

Anatomy

Lectures of Introduction

Second Stage

2018-2019

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Introduction: Dr.Shaxawan

Anatomy: is the science that deals with the structure and function of the

body.

Clinical anatomy: is the study of the macroscopic structure and function

of the body as related to the pract ice of medicine and other health

sciences.

Terms Related to Position:

All descript ions of the human body are based on the assumption that the

person is standing erect, with the upper l imbs by the sides and the face

and palms of the hands directed forward (Fig. 1). This is the so-called

anatomic position .

Median Sagittal Plane:

This is a vert ical plane passing through the center of the body, dividing it

into 2 equal right and lef t halves (Fig. 1).

Paramedian planes:

Are any planes that pass parallel to the median sagit tal plane at any side

of it.

Coronal Planes:

Are imaginary vert ical planes at right angles to the median sagittal plane

(Fig. 1).

Horizontal, or Transverse, Planes:

These planes are at right angles to both the median and the coronal

planes (Fig. 1).

Anterior: Any structure that is closer to the f ront of the body is said to be

anterior.

Posterior: Any structure that is closer to the back of the body is said to

be posterior (Fig. 1).

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Medial: Any structure situated nearer to the med ian plane of the body

than another structure.

Lateral: Any structure situated farther away f rom the median plane than

another structure (Fig. 1).

Superior: any structure that l ies nearer to the upper end of the body (the

head) than another structure.

Inferior: any structure that l ies nearer to the lower end of the body (the

sole of the foot) than another structure (Fig. 1).

Superficial and deep: describe the relat ive distances of structures f rom

the surface of the body.

Proximal and Distal: describe the relative distances of structures f rom

the roots of the l imbs; for example, the arm is proximal to the forearm and

the hand is distal to the forearm (Fig. 1).

Internal and external: describe the relat ive distance of structures f rom

the center of an organ or cavity; for example, the internal carot id artery is

found inside the cranial cavity and the external carot id artery is f ound

outside the cranial cavity.

Supine position: is the posit ion when the body is lying on the back.

Prone position: is the posit ion when the body is lying with face

downwards.

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Figure (1): Anatomic terms used in relat ion to posit ion.

Terms Related to Movement:

Flexion: decreasing the angle between 2 parts of the body . It is usually

an anterior movement, but it is occasionally posterior, as in the case of

the knee joint (Fig. 2).

Extension: means straightening the joint and is usually a posterior

movement, but it is occasionally anterior, as in the case of the knee joint

(Fig. 2).

Abduction: is a movement of a l imb away f rom the midline of the body

(Fig. 2).

Adduction: is a movement of a l imb toward the body (Fig. 2).

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Rotation: is the movement of a part of the body around its long axis.

Medial rotation: is the movement that results in the anterior surface of

the part facing medially.

Lateral rotation: is the movement that results in the anterior surface of

the part facing laterally.

Circumduction: is the combination in sequence of the mo vements of

f lexion, extension, abduction, and adduction (Fig. 2).

Figure (2): Some anatomic terms used in relation to movement.

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Basic Structures: Dr.Shaxawan

Skin:

The skin is the largest organ of the body. It is divided into two parts: the

superf icial part, the epidermis, and the deep part, the dermis (Fig. 3).

Epidermis:

It is a strat if ied epithelium whose cells become f lattened as they mature

and rise to the surface.

Dermis:

It is composed of dense connective t issue containing many blood vessels,

lymphatic vessels, and nerves.

It shows considerable variat ion in thickness in dif ferent parts of the body,

tending to be thinner on the anterior than on the posterior surface. It is

thinner in women than in men.

Skin appendages:

1. Nails: are kerat inized plates on the dorsal surfaces of the t ips of the

f ingers and toes.

2. Hairs: grow out of hair foll icles , which are invaginations of the

epidermis into the dermis (Fig. 3). Hairs are distributed over the whole

surface of the body, except on some areas such as: the l ips, palms of the

hands & soles of the feet.

A band of smooth muscle, the arrector pili , connects the foll icle to the

superf icial part of the dermis (Fig. 3). Contract ion of this muscle causes

the hair to move into a more vert ical posit ion. The pull of the muscle also

causes dimpling of the skin surface, so -called gooseflesh .

3. Sebaceous glands: pour their secret ion, the sebum, onto the shafts of

the hairs (Fig. 3).

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4. Sweat glands: are long, spiral glands distributed over the surface of

the body, except on the red margins of the l ips, nail beds, glans penis and

clitoris (Fig. 3).

Fasciae:

The fasciae of the body l ie between the sk in and the underlying muscles

and bones. They can be divided into two types:

1. Superficial fascia (or subcutaneous tissue): is a mixture of loose

areolar & adipose t issue that unites the dermis of the skin to the

underlying deep fascia. It tends to be thicker in women than in men.

2. Deep fascia is a membranous layer of connective t issue that invests

the muscles and other deep structures .

Figure (3): General structure of skin & its relat ion to superf icial fascia .

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Muscle:

The three types of muscle are skeletal, smooth, and cardiac.

1) Skeletal Muscle:

Skeletal muscles produce the movements of the skeleton; they are called

voluntary muscles .

A skeletal muscle has two or more attachments. The attachment that

moves the least is called the origin , and the one that moves the most, the

insertion (Fig. 4). The f leshy, reddish & contract i le part of the muscle is

called belly (Fig. 4).

The ends of a muscle are attached to bones, cart i lage, or l igaments by

cords of f ibrous t issue called tendons (Fig. 5).

Occasionally, f lattened muscles are attached by a thin but strong sheet of

f ibrous t issue called an aponeurosis (Fig. 5).

Figure (4): Origin, insert ion & belly of gastrocnemius muscle.

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Figure (5): Examples of a tendon (1), & an aponeurosis (2).

2) Smooth Muscle:

Smooth muscles consist of long, spindle -shaped cells closely arranged in

bundles or sheets. They are involuntary (not under our control) and have

no striat ions (unstriated muscles).

They are found inside:

1. The tubes of the body, e.g., the gastrointest inal tract.

2. Walls of storage organs, e.g., the urinary bladder and the uterus.

3. Walls of the blood vessels.

3) Cardiac Muscle:

Cardiac muscles consist of striated muscle f ibers that branch and unite

with each other (striated muscles). They form the myocardium of the

heart. Cardiac muscles are involuntary & are supplied by autonomic

nerves.

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Joints: Dr.Shaxawan

A joint is a site where two or more bones come together, whether there is

movement or not. Joints are classif ied into 3 types according to the

t issues that l ie between the bones:

1. Fibrous Joints:

The art iculat ing surfaces of the bones are joined by f ibrous t issue ( Fig. 6),

and thus very l i t t le or no movement is possible, e.g., the sutures of the

vault of the skull.

2. Cartilaginous Joints:

Cart i laginous joints can be divided into two types:

A) Primary cartilaginous joint: the bones are united by hyaline

cart i lage, e.g., union between the epiphysis and the diaphysis of a

growing bone. No movement is possible.

B) Secondary cartilaginous joint: the bones are united by

f ibrocart i lage & the art icular surfaces of the bones are covered by hyaline

cart i lage, e.g., the joints between the vertebral bodies (Fig. 6).

A small amount of movement is possible.

3. Synovial Joints:

The art icular surfaces of the bones are covered by hyaline cart i lage

separated by a joint cavity (Fig. 6). The cavity of the joint is l ined by

synovial membrane . The synovial membrane is protected on the outside

by a membrane called the capsule .

The joint is lubricated by a f luid called synovia l f luid , which is produced

by the synovial membrane.

There is a great degree of movement.

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Figure (6): Types of joints, (A) Fibrous joint (sutures of skull), (B)

cart i laginous joint (between vertebral bodies), (C) Synovial jo int (hip joint)

Types of synovial joints:

Synovial jo ints can be classif ied according to the arrangement of the

art icular surfaces and the types of movement that are possible (Fig. 7):

1. Plane joints: sternoclavicular & acromioclavicular joints.

2. Hinge joints: elbow, knee, and ankle joints.

3. Pivot joints: at lantoaxial jo int .

4. Condyloid joints: metacarpophalangeal (knuckle) joints.

5. Ellipsoid joints: wrist jo int.

6. Saddle joints: carpometacarpal joint of the thumb.

7. Ball-and-socket joints: hip & shoulder joints .

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Figure (7): Different types of synovial joints. 1. Plane joints. 2. Hinge joint. 3. Pivot joint.

4. Condyloid joint. 5. Ellipsoid joint. 6. Saddle joint. 7. Ball-and-socket joint.

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Bone: Dr.Shakhawan

Bone is a type of connective t issue that consists of cells, f ibers, and

matrix. It is hard because of the calcif icat ion of its extracellular matrix.

Bone exists in two forms:

1. Compact bone .

2. Cancellous (spongy) bone (Fig. 8).

Functions of bones:

1. Protect ion of vital structures , for example, the skull and vertebral

column protect the brain and spinal cord.

2. Support of the body.

3. Serves as a lever, as in the l imbs.

4. Storage of calcium salts.

5. Synthesis new blood cells.

Classification of Bones:

Bones may be classif ied into: (Fig. 8)

1. Long Bones: are found in the l imbs (e.g., the humerus, femur,

metacarpals & metatarsals). They have a shaft, the diaphysis , and

an epiphysis at each end.

2. Short Bones: are found in the hand and foot (e.g., the scaphoid,

talus, and calcaneum).

3. Flat Bones: are found in the vault of the skull (e.g., f rontal and

parietal bones).

4. Irregular Bones: include those not assigned to the previous

groups (e.g., bones of the skull, the vertebrae, & the pelvis).

5. Sesamoid Bones: are small bones that are found in certain

tendons where they rub over bony surfaces. The function of a

sesamoid bone is to reduce f rict ion on the tendon. The largest

sesamoid bone is the patella.

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Figure (8): Different types of bones. A. Long bone. B. Irregular bone. C. Flat bone. D.

Sesamoid bone.

Cartilage:

Cart i lage is a semi-rigid form of connective t issue. There are 3 types:

1. Hyaline cartilage: covers the art icular surfaces of nearly all

synovial jo ints.

2. Fibrocartilage: is found in the discs within joints (e.g.,

sternoclavicular joint, and knee joint).

3. Elastic cartilage: is found in the auricle of the ear, external

auditory meatus, auditory tube, and epiglott is.

Hyaline cart i lage & f ibrocart i lage tend to calcify or even ossify in later l ife.

Ligaments:

A ligament is a cord or band of connective t issue unit ing two structures.

They are commonly found in associat ion with joints.

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Blood Vessels:

Blood vessels are of three types: arteries, veins, & capil laries .

Arteries:

are vessels or tubes (Fig. 9) that transport blood f rom the heart to the

various t issues of the body. All arteries carry oxygenated blood, except

the pulmonary artery which carr ies deoxygenated blood f rom the heart to

the lungs. Arteries do not have valves.

There are 3 types of arteries:

1. Large (elastic) arteries: aorta & pulmonary artery.

2. Medium-sized (muscular) arteries: brachial artery & femoral artery.

3. Small arteries & arterioles: Arteriole is the smallest artery .

Veins:

are vessels or tubes that transport blood back to the heart f rom dif ferent

parts of the body. All veins ca rry deoxygenated blood , except the

pulmonary veins which carry oxygenated blood f rom the lungs to the

heart. Most veins have valves. There are 3 types of veins: large veins,

medium-sized veins & venules (Fig. 9).

Capillaries:

are microscopic vessels in the form of a network connecting the arterioles

to the venules (Fig. 9).

Figure (9): Different types of blood vessels.

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Lymphatic System: Dr.Shakhawan

The lymphatic system consists of lymphatic t issues and lymphatic vessels.

Lymphatic tissue: is a type of connective t issue that contains large

numbers of lymphocytes. It is found in the following organs: the thymus,

the lymph nodes & the spleen. Lymphatic t issue is essential for the

immunologic defenses of the body against bacteria and viruses.

Lymphatic vessels: are tubes that return the lymph of the body to the

blood. They are found in all organs of the body except the central nervous

system, eyeball, inner ear, epidermis of skin, cart i lage, and bone.

Nervous System:

The nervous system is divided structurally into 2 main parts: central

nervous system , which consists of the brain & spinal cord, & peripheral

nervous system , which consists of cranial nerves & spinal nerves.

Functionally , the nervous system can be further divided into somatic

nervous system , which controls voluntary act ivit ies, and autonomic

nervous system , which controls involuntary act ivit ies.

Central Nervous System (CNS):

The central nervous system is composed of large numbers of nerve cells

(neurons) and their processes.

Peripheral Nervous System (PNS):

The peripheral nervous system consists of the cranial and s pinal nerves.

Cranial Nerves:

There are 12 pairs of cranial nerves that leave the brain and pass through

foramina in the skull.

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Spinal Nerves:

31 pairs of spinal nerves leave the spinal cord. These are: 8 cervical, 12

thoracic , 5 lumbar , 5 sacral, and 1 coccygeal.

Each spinal nerve is connected to the spinal cord by two roots: the

anterior root and the posterior root (Fig. 10). The anterior root consists

of bundles of nerve f ibers carrying nerve impulses away f rom the CNS.

Such nerve f ibers are called efferent (motor) f ibers. The posterior root

consists of bundles of nerve f ibers that carry impulses to the CNS and are

called afferent (sensory) f ibers (Fig. 10).

Figure (10): Cross section of thoracic segment of spinal cord showing the spinal nerve.

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Autonomic Nervous System (ANS):

This is the part of the nervous system concerned with the innervation of

involuntary structures such as the heart, smooth muscle, & glands.

The ANS is divided into two parts: the sympathetic and the

parasympathetic .

The sympathetic part of the ANS prepares the body for an emergency

(“f l ight or f ight” response) .

Increases heart rate

Increases breathing rate

Increases blood pressure

Dilates pupils

Inhibits digestion & peristalsis of intest ine.

Closes the sphincters

The parasympathetic part of the ANS aims to conserve energy. It brings

things back to normal:

Decreases heart rate.

Decreases breathing rate.

Blood pressure returns to normal.

Constricts pupils

St imulates digestion & peristalsis

Opens the sphincters