skeletal system Flashcards
Long Bones
. Longer than they are wide
. Act as levers to create movement
. Produce red blood cells
. have a shaft known as diaphysis and two extended ends called epiphysis
eg. Humerus, Tibia, Femur
Short Bones
. Are as long as they are wide
. Used for weight bearing
. Absorb shock
. consists of a cancellous bone surrounded by thin layer of compact bone
eg.Tarsals, Carpals
Flat Bones
. Wide and flat, normally thin
. Protect vital organs
. Attach muscles and produce blood
eg. Sternum Ribs Pelvis
Irregular
. Irregular shape
. Many functions such as, protection, attach muscles, support, movement,
eg. Lumbar, Thoracic, Cervical
Sesamoid
. Held within a tendon
. Reduce friction between the joint (smooth surface for tendon to slide over)
eg. Patella
Axial Skeleton
Is the main core or axis of the skeleton:
Cranium
Sternum
Ribs
Vertebral Column
Appendicular Skeleton
Contains bones that are attached to the axial skeleton
Limps
Shoulder girdle (Scapula)
Pelvic girdle
Cervical Vertebrae
7 cervical vertebrae. The first two are called axis and atlas and form a pivot joint that allows the head to move, They also the attach muscles of the neck.
Thoracic Vertebrae
12 thoracic vertebrae. They are bigger than the cervical and attach the ribs which protect the heart and lungs. They attach the muscles of the back.
Lumbar
5 lumbar vertebrae. They are the biggest of the moveable vertebrae. They support the weight of the other vertebrae and attach the muscles of the lower back.
Sacral
5 sacral vertebrae that are fused together. It helps form the wall of the pelvis. it also supports the weight of the vertebrae
Coccygeal
4 coccygeal vertebrae that are fused together. Has no function
Neutral Spine
A good posture with the correct position of the three natural curves (S shape). When
viewing the spine from the front (anterior), it should be completely vertical. Occasionally the spine may suffer from disorders which can cause the natural curves to change.
Kyphosis
The excessive outward curve of the thoracic region of the spine resulting in a ‘hunchback’
appearance. This is often caused by poor posture but can be caused by deformities of the vertebrae.
Scoliosis
The abnormal curvature of the spine either to the left or to the right (lateral curvature).
Most likely to occur in the thoracic region. Often found in children but can be found in
adults. This condition is not thought to be linked to bad posture and the exact reasons
for it are unknown, although it seems to be inheritable.
Process of bone growth
. Ossification= the process whereby the bones are formed
1. bones start as cartilage and harden through ossification
2. osteoblasts build new bone/ change cartilage to bone by bringing calcium to bone
3. osteoclasts break down bone (remove the excess calcium)
4. epiphyseal plates seal off once bone is fully grown.
. Calcium and phosphate accumulate on the cartilage, trapping it, causing the cells of cartilage to die. Tiny spaces are left when the cartilage dies. Blood vessels grow in these spaces and transport osteoblasts and nutrients to the developing bone.
(activity increases the uptake of minerals)
. Exercise reduces the risk of osteoporosis
. End of each long bone= long (epiphyseal) plates, allow the bone to grow longer
. Once the bone is formed the head fuses with the mainshaft, creating the epiphyseal line
Function of skeleton: protection
The skeleton protects vital organs:
Cranium protects the brain
Pelvis protects the reproductive organs
Ribs protect the heart and lungs
Function of skeleton: Attachment for Skeletal Muscle
. Bones provide anchors for muscles to attach.
. Tendons attach muscles to bone
. muscles pull on bones to create movement
Function of skeleton: Leverage
Long bones provide a lever system against which muscles can pull to create movement
Function of skeleton: Storing of Minerals
Bones store minerals such as calcium and phosphorus which is essential for bone growth and maintenance of bone health
function of skeleton; A Source of Blood Cell production
Bone marrow stored in bones produces red and white blood cells. Red blood cells carry oxygen for energy. White blood cells fight infection
Function of skeleton: Support Framework
Bones give your body shape and help support the body so we can stand up straight and attach muscles
Function of skeleton: Weight Bearing
Bones are very strong and will support the weight of the body the pelvis and tarsals supports the weight of the body
Function of skeleton: Reduce friction Across a Joint
The skeleton has many different types of joints. Synovial joint secrete synovial fluid that reduces friction between bones
Fixed Joint (Fibrous)
. These joints are fixed and allow no movement between bones
. They form when bones interlock and overlap during childhood
. they are held together by bands of tough fibrous tissue
. eg. Cranium, Sacrum, Coccygeal
Slightly Moveable joint (Cartilaginous)
. These joints are slightly moveable
. the ends of bone are covered in smooth shiny covering called articular/ hyaline cartilage, which reduces friction between bones
. the bones are separated by pads of white fibrocartilage- and these can compress to allow slight movement at the joint
. eg. Between the individual vertebrae
Moveable joint (Synovial)
These are freely moveable joints. The shape of bones determines the range of movement
eg. Elbow (hinge), Shoulder (ball & socket) Thumb (saddle)
Synovial fluid
lubricates and reduces friction between bones. viscous liquid and provides nutrients to articular cartilage. Allows wider range of movement at the joint
synovial membrane
contains/ releases synovial fluid, that lubricates the joint so reduces friction
articular cartilage
prevents bones rubbing and acts as shock absorber
joint capsule
surround the synovial joint and protects/ stabilise it
ligament
joins bone to bone and helps stabilise joint
bursa
fluid sack, stops tendon rubbing on bone, allows range of movement around joint
hinge joint
. Only allow movement forward and back like a door
. Flexion/ Extension/ Plantar Flexion/ Dorsiflexion
. Knee: Femur, Tibia, Fibula, Patella
. Elbow: Humerus, Radius, Ulna
. Ankle: Tibia, Fibula, Tarsals
ball and socket
. the round end of one bone fits into the cup-shape socket in another bone allowing movement in all directions
. Flexion, Extension, Adduction, Abduction, Rotation, Circumduction
. Shoulder: Scapula, Humerus, Clavicle
. Hip: Pelvis, Femur
pivot joint
. Rotation
. neck- Cervical vertebrae: Axis, Axial
Condyloid joint
. similar to ball and socket but movement is forward/back and side to side (ligaments often prevent rotation)
. Flexion, Extension, Adduction, Abduction, Circumduction
. Wrist: Ulna, Radius, Carpals
Saddle joint
. similar to condyloid but surfaces are concave and convex, allowing movement forward/back and side to side
. Flexion, Extension, Adduction, Abduction, Circumduction
. Thumb: Carpals, Metacarpals
Gliding joint
. Limited movement in all directions
. Hands: Between the Carpals
. Feet: Between the Tarsals
short term response to exercise: Synovial fluid production
movement increases Synovial fluid production in the joint as mechanical movement means the synovial membrane releases more fluid, reduces friction between joints= increasing range of movement at the joint. When the fluid is released it becomes less viscous.
short term response to exercise: Uptake of minerals
Exercise= stimulates the uptake of calcium= makes the bones stronger with less chance of injury
short term response to exercise: Increased pliability of ligaments
Tendons more pliable= increase the range of movement at the joint
long term response to exercise: Increase in bone density and strength
Regular weight bearing exercise = bones bigger and stronger, = you are less likely to get injured such as a fracture
long term response to exercise: Increased ligament strength
Regular exercise = strengthens ligaments as collagen becomes aligned = stabilises the joint = less likely to get injured such as a dislocation
long term response to exercise: Increased thickness of articular cartilage
Regular exercise = thicken the articular cartilage = protect the joint from wear and tear
factors affecting the skeletal system: Arthritis
Cause= caused by general wear and tear over a long period of time= reduces the normal amount of cartilage tissue = may result in the ends of the bones rubbing together. Arthritis is= inflammation within a synovial joint= pain and stiffness in the joint
Treatment= lifestyle measures – such as maintaining a healthy weight and exercising regularly medication – to relieve your pain, supportive therapies – to help make everyday activities easier, surgery.
Prevention= Physical activity = joints produce more synovial fluid = joint lubrication/ reducing friction between the bones & provide minerals to the cartilage.
Non-weight baring activities (swimming and cycling)
factors affecting the skeletal system: Osteoporosis
Cause = weakening of bones caused by a loss in calcium /lack of vitamin D/ sedentary lifestyle. As you get older = bones slowly lose their mineral density and naturally become brittle, fragile and more likely to break under stress. Usually women 50+ as menopause causes hormones to make bones lose density.
Treatment= treating and preventing fractures, and using medicines to strengthen bones.
Prevention= physical activity = help prevent osteoporosis by promoting increased uptake of minerals within the bones = an increase in bone mineral density. Resistance training, weight bearing exercise, shock absorbing sports (rugby) is a good method of preventing osteoporosis as overloading the skeleton will increase bone density.
factors affecting the skeletal system: age
Cause= The skeletal system is a living tissue that is constantly growing and repairing itself so that it can provide support and protection. Resistance training (weight training) in children = bones are still growing so putting too much force on them = damage the epiphyseal plates which are found at each end of the long bones= stunted bone growth
Treatment= ensure a fitness program designed to not overwork, at any age, and allow bone growth.
Prevention= don’t do too much weight/ resistance training as a child. If correctly it is ok.
Figure 1 shows a synovial joint.
1 (a) Name the components of the synovial joint labelled A–C in Figure 1.
Joint capsule – A
(Articular/Hyaline) cartilage – B
Ligament – C
(b) Synovial fluid is a thick liquid found in synovial joints.
Give three functions of synovial fluid.
Award one mark for each function of synovial
fluid identified to a maximum three marks.
Provides lubrication for the joint (1)
Provides nutrients/nourishes the cartilage
(1)
Reduces friction between the bones /
preventing bones from rubbing together
(1)
Used as a shock absorber (1)
Increases the range of movement of a
joint(1)
Michael is a high jumper. He has recently experienced severe pain and his doctor has
diagnosed postural deviations.
2 Complete the table by:
(a) giving two types of postural deviation in Column A.
Kyphosis (1)- the rounding of the upper back/shoulders/thoracic region/Hunched back (1)
Scoliosis (1)- his spine has a sideways curve in the shape of an S or a C (1)
(a) Give an example of a flat bone.
Ribs (1)
Cranium (1)
Sternum (1)
Pelvis (1)
Scapula (1)
(b) State the function of a flat bone.
Protection for vital organs from damage/(e.g)
ribs protect the lungs (1)
Provide a site for muscle attachment (1)
