Pathfit quiz 1

Skeletal System

is the system of bones, associated cartilages and joints of human body. Together these structures form the human skeleton.

Skeleton

can be defined as the hard framework of human body around which the entire body is built.

Babies

270 - 300 bones

Adults

206 bones

Ligaments location

On the bones

Cartilage location

Between the joints

Stapes

Smallest bone (middle ear)

Bones
Cartilage
Joints

Components of human skeleton

Bones

is a tough and rigid form of connective tissue. It is the weight bearing organ of human body and it is responsible for almost all strength of human skeleton

Cartilages

is also a form of connective tissue but is not as tough and rigid as bone. The main difference in the cartilage and bone is the mineralization factor. Bones are highly mineralized with calcium salts while cartilages are not

Joints

are important components of human skeleton because they make the human skeleton mobile. A joint occurs between “two or more bones”, “bone and cartilage” and “cartilage and cartilage”.

Axial Skeleton
Appendicular Skeleton

Division of Human Skeleton

Axial Skeleton

forms the axis of human body. It consists of Skull, vertebral column and thoracic cage.

Skull
Vertebral Column
Rib Cage

All parts of Axial Skeleton

Skull

is that part of human skeleton that forms the bony framework of the head. It consists of 22 different bones that are divided into two groups: bones of cranium and bones of face.

Bones of cranium and bones of face

Skull has 22 bones that is divided into 2 groups

Cervical - 7
Thoracic - 12
Lumbar - 5
Sacral - 5
Coccygeal - 4

Vertebral columns has 33 vertebrae that consist of 5 groups

VERTEBRAL COLUMN

It is a flexible column of vertebrae, connecting the trunk of human body to the skull and appendages. It is composed of 33 vertebrae which are divided into 5 regions: Cervical, Thoracic, Lumbar, Sacral, and Coccygeal.

Rib Cage

It is a bony cage enclosing vital human organs formed by the sternum and ribs. There are 12 pairs of ribs that are divided into three groups: True ribs, False ribs, and Floating ribs

TRUE RIBS – 1st to 7th pairs
FALSE RIBS – 8th to 12th pairs
FLOATING RIBS – 11th to 12th pairs (Can be removed and used for Rhinoplasty)

3 groups of rib cage

Appendicular Skeleton

It is the skeleton of appendages of human body. It consists of Shoulder girdle, Skeleton of upper limb, Pelvic girdle and Skeleton of lower limb.

Shoulder Girdle
Skeleton of Upper Limb
Pelvic Girdle
Skeleton of Lower Limb

All parts of Appendicular Skeleton

Shoulder Girdle

It attaches the upper limb to body trunk and is formed by two bones: clavicle and scapula.

Clavicle

is a modified long bone and is subcutaneous throughout its position. It is also known as the beauty bone.

Scapula

is a pear shaped flat bone that contains the glenoid fossa for the formation of shoulder joint. It possesses three important processes: Spine of scapula, Acromion process and Coracoid process.

Spine of scapula
Acromion Process
Coracoid Process

Scapula has the glenoid fossa possesses 3 three important processes that are: 

Upper

The skeleton of each upper limb consists of 30 bones. These bones are: Humerus, Ulna, Radius, Carpals (8), Metacarpals (5), Phalanges (14).

HUMERUS

ULNA

RADIUS

CARPALS

METACARPALS

PHALANGES

Composition of the upper limb consisting 30 total bones

Pelvic Girdle

There are two pelvic girdles (one for each lower limb) but unlike the pectoral girdles, they are jointed with each other at symphysis pubis. Each pelvic girdle is a single bone in adults and is made up of three components: Ileum, Ischium and Pubis.

Ileum
Ischium
Pubis

Pelvic Girdle consist of 3 components which are:

Humerus

Upper arms

Ulna
Radius

Lower Arm

Carpals

Wrist 8 bones

Metacarpals

Palm 5 bones

Phalanges 14 bones

Fingers and toes

Lower Limb

The skeleton consists of 30 bones. These bones are; Femur, Tibia,Fibula, Patella, Tarsals (7), Metatarsals (5), Phalanges (14).

Femur
Tibia
Fibula
Pattela
Tarsals
Metatarsals
Phalanges

Lower limb has 30 bones that consist of:

Femur

Longest and strongest bone

Tibia

Legs of the skeleton

Fibula

Thin part under tibia

Patella

Knee caps

Tarsals

Ankle in skeleton

Metatarsals

Palm of your feet (Talampakan)

STRENGTH, SUPPORT AND SHAPE
PROTECTION OF DELICATE ORGANS
LEVERAGE FOR MOVEMENTS

PRODUCTION OF RED BLOOD CELLS

Functions of human skeleton

STRENGTH, SUPPORT AND SHAPE

It gives strength, support and shape to the body. Without a hard and rigid skeletal system, human body cannot stand upright, and it will become just a bag of soft tissues without any proper shape

PROTECTION OF DELICATE ORGANS

In areas like the rib cage and skull, the skeleton protects inner soft but vital organs like heart and brain from external shocks. Any damage to these organs can prove fatal, therefore protective function of skeleton is very important

LEVERAGE FOR MOVEMENTS

Bones of the human skeleton in all parts of body provide attachment to the muscles. These muscles provide motor power for producing movements of body parts. In these movements the parts of skeleton acts like levers of different types thus producing movements according to the needs of the human body.

PRODUCTION OF RED BLOOD CELLS

Bones like the sternum, and heads of tibia have hemopoeitic activity (blood cells production). These are the sites of production of new blood cells.

Muscular System

more than 600 different types of muscle are in the human body

To provide movement

Primary purpose of the muscular system

What do we need to know about the Muscular System

The human body is composed of 650 individual muscles which are attached to the skeleton. 2. They provide movement for the body. 3. They serve for postural support. 4. They produce heat during periods of cold stress.

What are the distinct functions of the muscles?

They give specific shape to the different parts of the body.

They provide movement for the body.

They serve for postural support.

They produce heat during periods of cold stress

SKELETAL MUSCLES (STRIATED OR VOLUNTARY MUSCLES)

These muscles are capable of performing wide variety of movement depending on the type of joint and muscles involved.

They are attached to the bones by tough connective tissues called tendons

Makes up about 40% of an adults’ body weigh

CARDIAC MUSCLES

Known as the heart muscles

The heart wall

Compose of 3 layers

Myocardium

is responsible for the heart’s pumping action.

Cardiocytes

Cardiac muscle is made from cells called

SMOOTH MUSCLES (UNSTRIATED OR INVOLUNTARY MUSCLES)

contractions are involuntary movements triggered by impulses that travel through the autonomic nervous system to the smooth muscle tissue

The smooth muscle of the alimentary canal

facilitates the peristaltic waves that move swallowed food and nutrients.

Contractability

Excitability

Exstensibility

Elasticity

CHARACTERISTICS OF MUSCLES

Contractility

Muscle tissue has the ability to contract and shorten. Muscles can actively shorten, but they cannot actively lengthen themselves. They must rely on their antagonist muscle(s) or another external forces such as gravity to help them lengthen

Excitability

This is the characteristic of muscle tissue that describes the muscle’s ability to respond to a stimulus. When a motor neuron sends a signal to the muscle, it contracts.

Entensibility

This means that muscle tissue can be stretched. When there is tightness of a muscle group, for example at the hamstring or pectoral muscles, it is usually not the muscle tissue itself that is the problem. The tightness usually comes from restrictions in the fibrous connective tissue (fascia) that surrounds the muscle tissues.

Elasticity

This is the ability of muscle tissue to recoil or come back to its original length after being stretched