Chapter 36 - The Skeleton And Muscles Flashcards
What controls the skeletal and muscles system?
Nervous system
What are the 5 functions of the skeleton?
Framework - support
Shape - tall
Protection - skull protects the brain etc
Movement - rigid levers that the muscles can pull
Manufacture of blood cells - bone marrow makes blood components
How many bones are in an adult body?
206
What are the names of the two parts of the skeleton?
Axial skeleton - skull, vertebrae, ribs, sternum
Appendicular skeleton - everything else
How many bones are in the skull?
22 bones fused together
How many vertabrae are in the spine?
33
What is the function of the vertebrae?
To protect and surround the nerves of the spinal cord
What is between the vertebrae?
Pad of fluid enclosed by cartilage called a disc
What is the function of the discs between vertabrae?
Shock absorbers and protect against the vertabrae from rubbing again each other
What are the five regions of the spine?
Cervical (neck) - 7 Thoracic (chest) - 12 Lumbar (small of back) - 5 Sacrum (hip) - 5 fused together Coccyx (tail) - 4 fused together
What are the three types of ribs?
True ribs - 7 pairs - attached to sternum
False ribs - 3 pairs - attached to rib above
Floating ribs - 2 pairs - attached to nothing
What is the pectoral girdle?
Contains collarbone and shoulder blade (clavicle and scapulae)
What is the pelvic girdle?
Contains hip bones which is attached to sacrum, pelvis,
2 halves (3 pieces each) joined by cartilage
Fused to spine
What bones are in the arm?
Numerous, radius, ulna, carpels (wrist), metacarpals (hand), phalanges (fingers)
What are the bones in the legs?
Femur, patella (knee), tibia (shin), fibula, tarsals (ankles), metatarsals (foot), phalange (toes)
What is compact bone made from?
Osteoblasts
What are osteoblasts?
Bone cells enclosed in a matrix
What do osteoblasts consist of?
70% inorganic salts (phosphate, calcium)
30% organic material (collagen)
Where is bone marrow?
Medullary cavity
What types of bone marrow are there?
Red - active in making blood cells
Yellow - inactive and contains numerous fat storage cells
What is spongy bone?
Consists of a mixture of compact bone with pockets of bone marrow
Gives strength and rigidity to bones without making them too heavy
What is cartilage?
A flexible material that consists of protein fibers embedded in a matrix. Protects the ends of bones and acts as a shock absorber
What is a periosteum?
Surrounding membrane of a long bone
Consists of blood vessels and nerves
Why is cartilage slow to heal?
Lacks blood supply and nerves, relies on diffusion
What is a joint?
Where two or more bones meet
What are three categories of joints?
Immovable - don’t move e.g. pelvic girdle
Slightly moveable - move a little e.g. vertabrae
Freely moveable - moveable e.g. synovial joints
What is synovial fluid?
Lubricates and reduces friction between bones. End of bone covered by cartilage.
What is a ligament?
Connect bone to bone
Strong, fibrous, slightly elastic
More flexible when warm
What is a tendon?
Connect muscle to bone
Strong, flexible, inelastic fibres
Composed of collagen
What are the two types of joints?
Hinge joints e.g. elbow
Ball and socket joint e.g. shoulder
What is a hinge joint?
Allows movement in one direction only
Supports heavy loads
What is a ball and socket joint?
Allows movement in all directions
Name a musculoskeletal disorder
Arthritis - painful disorder where there is inflammation in joints
Results in swelling, pain
What are the two types of arthritis?
Osteoarthritis - occurs from 50 years onwards, cartilage in synovial joints worn down
Rheumatoid arthritis - most severe form, genetic, immune system turns on itself, synovial membranes attacked and then swelling occurs
How to prevent arthritis?
Reduce damage to joints by use of proper footwear, exercise on soft ground
How to treat arthritis?
No cure
Reduce pain by rest, weight loss, anti inflammatory medications, replace joint
What are muscles made of?
Protein
What are the three types of muscles?
Involuntary (smooth) - located in intestines, bladder, involuntary control, slow to tire
Cardiac muscle - located in heart, contracts quickly and doesn’t tire, involuntary
Voluntary (skeletal or striped) - muscle that causes body movements, contracts quickly but tires easily
What is an antagonistic pair of muscles?
Two muscle work together that have opposite effects
One muscle is needed to move another muscle.
Give an example of an antagonist pair of muscles?
Upper arm: tricep contracts to lower forarm
Biceps contracts to raise forarm
What is embryonic cartilage?
Replaced with bone 8th week in uterus
What do osteoblasts do?
Produce collagen
What is a calcium phosphate?
Surrounds collagen fibres
Makes a hard material
How do bones grow?
Growth plate causes cartilage to form and ossify
Where is the growth plate?
Between epiphysis and diaphysis
What is osteoporosis?
Loss of protein from bone, bone becomes brittle
How do bones develop?
Osteoblasts form compact bone around external surface
Osteoclasts break down bone on internal surface around medullary cavity
These two processes at the same time increase diameter of bone
What 3 factors affect bone development?
Stress on bones causes osteoblast stimulation
Hormone levels - puberty
Calcium in diet
What is parathormone?
Removes calcium from bone into blood - essential for muscles and nerves.
