Sports Science - Chapter 1 (Anatomy)

axial skeleton

axial skeleton

ribs, sternum, vertebral column, skull

vertebral column

(from the top) cervical, thoracic, lumbar, sacral (fused), coccyx (fused)

appendicular skeleton

all bones but the ribs, sternum, skull and vertebral column

(function of bones) - support and maintenance

the skeleton provides a framework for the body

(function of bones) - protection of vital organs

ribcage surrounds the heart and lungs, the pelvic girdle protects the reproductive organs, skull protects the brain

(function of bones) - provides attachment points for muscles

bone and muscle are attached by tendons, muscles and tendons contract causing movement at the joints

(function of bones) - storage and release of minerals (calcium and phosphorus)

bones store calcium and phosphorus which are important for muscle contraction and nerve activity, they are released into the blood to maintain mineral homeostasis and are distributed around the body

(function of bones) - blood cell production

erythrocytes, leukocytes and platelets are produced in red bone marrow, usually located in flat bones

(function of bones) - storage of energy

lipids are stored in adipose tissue in the yellow bone marrow, which is found in the hollow core of bones, especially long bones. lipids provide important energy reserves.

differences between appendicular and axial skeletons

axial skeleton provides protection to vital organs, whereas the appendicular skeleton provides more attachment points for muscles, which allows the body to engage in movement

long bone

bones that are longer than they are wide, with a shaft and two ends e.g., femur, humerus, and tibia

short bones

bones that are as long as they are wide, providing support and stability, as well as limited motion e.g., bones in the wrist (carpals) and ankle (tarsals)

flat bones

thin cancellous bone that is sandwiched by 2 layers of compact bone, providing protection and a large surface area for muscle attachment e.g., scapula, ribs and sternum

irregular bones

irregular bones do not have a specific shape or pattern e.g., the vertebral column

inferior

below or further away from the head

superior

above or closer to the head

proximal

nearer to where a limb attaches to the body

distal

further away from where a limb attaches to the body

posterior

behind or nearer to the back

anterior

forward or closer to the front

internal

located inside or inside the surface

external

located outside or outside the surface

lateral

located away from the midline

medial

located close to the midline

tendons

connects muscle to bone

ligaments

connects bone to bone

cartilage

prevents the end of bones rubbing together at joints

joint

a joint occurs where 2 or more bones articulate (come into contact)

fibrous joint

thin layer of fibrous tissue connecting two bone, continuous with the periosteum, no movement is allowed e.g., skull

cartilaginous joint

bones that are separated by a fibrocartilage disc (thicker, stiffer cartilage) or by a thick layer of hyaline cartilage (softer), limited movement, e.g., sternum

synovial joint

most common joint in the body and important for mobility, large amount of movement permitted

hinge joint

allow movement in one direction (like a door hinge) e.g., knee and elbow

saddle joint

allows movement in two planes, formed by the articulation of two bones that have concave and convex surfaces resembling a saddle e.g., the joint between the thumb and the wrist

condyloid joint

allows for movement in two planes, permits flexion, extension, abduction, adduction, and circumduction movements, e.g., wrist

pivot joint

allows for rotation and movement in multiple directions e.g., between radius and ulna (forearm), neck

gliding joint

allows bones to glide or slide past each other e.g., wrists, ankles, and between the vertebrae of the spine

ball and socket joint

the rounded head of one bone fits into the concave socket of another bone, allows for a wide range of motion in multiple directions e.g., the shoulder and hip joints

synovial fluid

reduces the friction between the articular cartilage of synovial joints during movement

bursae

tiny, slippery sacs of fluid that facilitate the gliding movement by providing a thin cushion and reducing friction between the surfaces

articular capsule

a dense fibrous connective tissue that is attached to the bones via special attachment zones and forms a sleeve around the joint

periosteum

thin, shiny white membrane that forms the outer lining of bones and is important for bone growth, repair, nutrition and attachment of ligaments and tendons

joint cavity

filled with synovial fluid, made up of an outer layer of a fibrous membrane which keeps the bones together structurally and an inner layer (synovial membrane) which seals the synovial fluid

articular (hyaline) cartilage

smooth, white tissue that covers the end of bones where they come together to form joints, allows the bones to glide over each other with very little friction, can be damaged

synovial membrane

a layer of connective tissue that lines the cavities of joints, tendon sheaths and bursae, makes synovial fluid

contractibility (muscle characteristic)

the ability of a muscle to contract forcefully

extensibility (muscle characteristic)

ability for muscle to lengthen beyond its normal resting length

elasticity (muscle characteristic)

ability for muscle to recoil back to its original length after stretching

atrophy (muscle characteristic)

the decrease of muscle size due to the lack of exercising the muscle

controlled by nerve stimuli (muscle characteristic)

this allows movement to occur (motor neurons)

fed by capillaries (muscle characteristic)

these supply nutrients and oxygen and removes waste

skeletal muscle

under voluntary control, has a striated appearance, has tendons that attaches to bone, main function is movement of the skeleton

cardiac muscle

under involuntary control, striated appearance, makes up the thicker middle layer of the heart, contractions like pregnancy

smooth muscle

lines the walls of blood vessels and hollow organs such as the stomach and intestines, involuntary muscle contraction

origin

the attachment of a muscle tendon to a stationary bone

insertion

the attachment of a muscle tendon to a moveable bone