IB Exam Review Unit 1 Flashcards
What are the functions of the skeletal system? (4)
- protection of vital organs
- support or maintenance of posture
- providing attachment points for the muscles
- storage/release of minerals
How many types of vertebrae are there?
5
What are the types of vertebrae? (5)
- cervical
- thoracic
- lumbar
- sacral
- coccyx
Cervical Vertebrae
smallest and most movement
Thoracic Vertebrae
less mobile because ribs attach to side of the vertebra
Lumbar Vertebrae
largest and responsible for weight bearing
Sacral Vertebrae
transmits weights from the body to the pelvis and the legs
What are the functions of the axial skeleton? (3)
- provides protection
- support
- attachment sites for muscles
What are the components of the pelvic girdle? (3)
- ilium
- ischium
- pubis
What is the function of the appendicular skeleton?
movement
What is the function of the humerus?
attaches muscles for movement of arm, hand, and elbow
What is the function of the patella?
helps leg extension and protect knee joint
What are features of long bones? (4)
- longer than wide
- work as levers
- have long cylindrical shafts with enlarged ends
- are essential for movement
What are features of short bones? (3)
- small, compact, and cube shaped
- articulate with more than one bone
- provide stability
What are features of flat bones? (3)
- curved, flat surfaces
- protect organs
- allow muscle attachment
What is a feature of irregular bones?
they have varied size, shape, and surface area
What is the composition of bone? (4)
- contains several layers
- ends have cartilage for shock absorption
- red marrow inside end of bones
- yellow marrow inside of middle of bones
Spongy Bone
resists stress of weight and changes in posture, contains red marrow
Red Bone Marrow
produces blood cells
Epiphysis
ends made of spongy bone
Articular Cartilage (2)
- reduces friction
- provides shock absorption
Diaphysis (2)
- middle region made of compact bone
- resists bending forces
Compact Bone
solid, dense bone to provide protection and support
Periosteum
white membrane that provides nutrients & cells for growth after fracture
marrow cavity
space in diaphysis to store yellow bone marrow
yellow marrow
stores fat
Cartilage (4)
- add protection by shock absorption
- firm
- smooth
- non vascular
Ligaments (3)
- provide joint stability
- resist unwanted movements at joints
- strong and fibrous
Tendons (2)
- adds stability
- round band of connective tissue
Joint
where two or more bones articulate
What is the function of a joint?
increase mobility of the body and limbs
Fibrous Joints (3)
- no movement
- stable
- held fibrous connective tissue
Cartilaginous Joints (3)
- limited movement
- less stable
- held by cartilage
Synovial Joint (3)
- substantial movement
- least stable
- space between bone
Articular Capsule
strong tissue covering the joint that gives the joint stability & stops unwanted material from entering
Synovial Fluid (3)
- fluid inside joint cavity that lubricates and cushions end bones
- provides nutrients
- removes debris
Bursae
sacs of synovial fluid that reduce friction
Meniscus
crescent-shaped pad of cartilage prevents wear & provides cushioning
How many synovial joints are there? (REMEMBER TO USE THE KNOWT SET)
6
Gliding (2)
- between carpals
- between intervertebral joints
Hinge (3)
- elbow
- ankle
- phalanges
Condyloid Joint (2)
- between radius and carpals
- skull & 1st vertebra
Saddle
carpal and metacarpal of thumb
Ball and socket
hip and shoulder
Pivot
radius and ulna
What are the functions of muscles? (4)
- cause joint movement
- move substances within the body
- stabilize and maintain body positions
- generate up to 85% of body heat
What are characteristics of muscle tissue? (4)
- contractility
- extensibility
- atrophy
- hypertrophy
Epimysium
outer surrounding layer of muscle
Perimysium
surrounds bundles of muscle fibers
Endomysium
surrounds individual muscle fibers
Muscle fiber
single muscle cell that allows for muscle movement
Myofibril
contractile fibers that extend length of the cell
Sarcomere
smallest contracting unit of a myofibril made of actin & myosin
Actin
globular protein that contributes to muscle contraction
Myosin
fibrous protein that works with actin in muscle contraction
Origin
attachment of a muscle tendon to a stationary bone
Insertion
attachment of a muscle tendon to a moveable bone
What are the muscles in the quadricep group? (4)
- rectus femoris
- vastus intermedialis
- vastus medialis
- vastus lateralis
What are the muscles in the hamstring group? (3)
- biceps femoris
- semitendinosus
- semimenbranosus
