Exercise Science Terminology

The 6 main functions of the skeletal system

Structure, movement, protection, size, shape, mineral resources

Outline the purpose of bone marrow

Bone marrow serves the purpose of producing blood cells within the body

Outline the purpose of the shape of bones

Determines size and body structure

Briefly explain how the shape of bones predisposes certain athletes to different sports

The shape or size of bones within a person is strongly correlated with what sports people can participate in through factors such as the distribution of gravity, mechanical power, and balance. An example of such is the length of bones within the arms, which may predispose someone to be more successful in sports such as weightlifting, swimming, etc.

Briefly describe movement

Muscles and joints are attached to specific bones to generate mechanical power, which imitates a lever and allows a muscle to move at a certain level.

State the two main connective tissues of the skeletal system

Ligaments, Tendons

Briefly outline the characteristics of Ligaments and Tendons

White, limited blood flow, connect muscles to bones and allows joint movement

Outline the differences between the axial and appendicular skeletal systems.

The Axial skeleton refers to the bones within the body that are unmoving, or are not attached to any limbs. The Appendicular skeleton refers to bones within the body that allow movement, or provide support to apendages within the body; eg, limb bones themselves and girdles.

Ulna

Hinge joint in the elbow- moves arm up and down

Radius

Palm rotation- forearm bone that twists

Tibia

Bone within the foot responsible for up/down and side movement

Humerus

Long bone within the arms located near the bicep/tricep

Fibula

Bone near the knee, responsible for joint movement

Patella

The knee bone itself; also serves to allow quadriceps tendons to connect with the lower leg

Carpal

The bone located within the wrist that connects to the fingers and serves as the “base” of the hand

Metacarpals

Middle finger bones

Phalanges

Lower finger bones

Ball/Socket Joints

Bones located near areas such as the shoulder or hip typically have a ball-like shape near the end of their structure to allow 180-360 degree movement of an apendage. Other bones such as the clavicle and scapula tend to form structures that allow the ball socket joints to fit into the skeleton.

Pelvic girdle

Located near the lower body, made up of a collection of bones such as the Pubis, ischium, Trillium

Patella

Knee bone- irregular

Vertebral Column

Series of repeating bones that surround the spinal chord

Sections of the Vertabral Column

Cervical (Neck)

Thoracic (Connected to the ribs)

Lumbar (Bones unfused to vertebrae)

Sacrum (Fused to sacral vertebrae such as pelvis; attachment join for muscles)

Coccyx (end of vertebrae)

Long bones

A long bone is usually located in the Appendicular skeletal system, such that they are a bone for the body’s limbs and appendages. The muscles surrounding them exert force onto the bones, similar to a lever, to create movement and generate mechanical force.

They also store the majority of the body’s bone marrow and produce blood cells.

Epiphysis

End of a long bone, red bone marrow, spongey bone

Diaphysis

Middle of bones, yellow bone marrow, compact bone

Distinguish compact bone and cancellous bone

Cancellous bone (spongey bone):

• Air pockets

• Red bone marrow

• Supported by cartilage and meniscus (shock absorber)

• Force exerted in the top of the bone allows bouncy/elastic movement

Compact bone

• Strong, durable

• In middle of bone to prevent breaking/snapping

• Yellow bone marrow

Periosteum

Membrane of bones, living tissue, contain osteoblasts (cells responsible for bone growth and stability)

Growth plate

Found in epiphysis, bone growth in length, once mature, growth plate fuses to form epiphyseal line

Short bones

Small, compact bones that generally serve as the base for smaller bones. They are light, strong, and composed of cancellous bone with a thin layer of compact bone on the outside.

Examples:

• Tarsels

• Carpals

Flat bones

Bones that protect vital organs, such as the skull and sternum. They are also areas for muscle attachment, such that muscles positioned higher than the bone itself can exert force (eg, mandibles).

Sesamoid Bones

Bones that grow within tissue rather than externally. Usually, sesamoid bones serve a particular function, and many are also irregular bones (eg, the patella).

Ossification

The process in which bone develops; from cartilage to bone.

Cartilage

Living tissue that is generally harder than muscle tissues.

Cartilage components and their purpose

Chondroblasts- active growing cells

Chondrocytes- mature cell from of cartilage

Osteogenic pathway

A distinct process in which a bone can develop from; such that there are two types, intramembranous ossification, and endochondral ossification.

Endochondral ossification

The process in which bone develops from cartilage; such that is serves as a precursor/template to bones themselves

Intramembranous ossification

The process in which bone develops directly from mesenchyme; such that bones are developed from connective tissue found in an embryo.

Length in a bone is grown through:

-the epiphyseal plates, in which tissue grows and cells divide. This growth, located within the such plates grow upwards.

Diameter in a bone is grown through:

-osteoblast deposits which are formed in thin layers underneath the periosteum.

Factors effecting bone growth

• Physical stress- bone withdrawn from gravity eg. weight lifting

• Hormone activity- stimulates formation of new bone tissue

• Nutrition

Osteoporosis

A condition that characterises the slow degradation of the bones or cartilages within the human body.