Skeletal System Overview
Biology 2121Chapter 7
Study Guide Notes 1. You are responsible for any bone covered in the lab.– Bone location – General function(s) of bone
2. PP Notes
3. Review/Objective Notes
Introduction
Skeletal System– Axial vs. Appendicular
– Number of Bones
Functions– 1. Support
– 2. Mineral and Lipid storage
– 3. Hematopoiesis
– 4. Protection
– 5. Leverage
Axial Skeleton – The Skull 1. Skull
– 22 facial and cranial bones
2. Cranium – (8) cranial bones – Thin, formed by intermembranous
processes – Protection; attachment site for head and
neck muscles – Encases the brain
2. Bones are held together by ‘sutures’ – Coronal, saggitial, squamous, lambdoid
3. Facial Bones– (14) facial bones– Functions
Vertebral Column
1. (26) bones total – 7 Cervical; 12 Thoracic; 5 Lumbar;
sacrum and coccyx – Curvature
2. Attachments – Longitudinal ligaments– Ligamentum flavum
3. Discs – Gelatinous; collagen and
fibrocartilage – Compressible
4. Structure and Differences – Differences between cervical,
thoracic and lumbar sections
Sacrum and Coccyx 1. Sacrum – (5) fused vertebrae– Sacral foramina
– Sacral nerves; BVs
– Sacral canal – Continuation of vertebral canal
– Forms joint with hip bones (sacroilliac joint)
2. Coccyx – (4) fused vertebrae– Mostly ‘useless’
Thoracic Cage 1. Function– Protects heart, lungs, blood vessels– Supports shoulder girdles, upper
limbs, attachments for muscles
2. Sternum – Attachment site for clavicles
(clavicular notch) – Xiphoid process ossifies around ‘40’ – Hematopoiesis
3. Ribs – (12) pairs; (7)-True; (5)-False; Last
pair – Floating – Joined by costal cartilage
Appendicular Skeleton – Pectoral Girdle 1. Pectoral ‘Shoulder’
– Attach upper limbs to axial skeleton; muscle attachment
2. Clavicles– Articulates with scapulae and sternum – Anchor muscles (deltoid; pectoralis major);
brace arms and shoulder
3. Scapulae – “spade or shovel” – Coracoid process (biceps; coracobrachialis) – Acromioclavicular joint
Upper, Lower Arm - Hand 1. Humerus– Tubercles (rotator cuff muscles);
deltoid tuberosity (deltoid) – Condyles (capitulum and trochlea) – Epicondyles (muscle attachments)
2. Ulna and Radius – Ulna (elbow joint) – Radius (radial tuberosity – biceps)
3. Carpus-Metacarpus-Phalanges – 8-carpal bones
Pelvic (Hip) Girdle1. Os coxae (hip bones)– Form pelvic girdle – Pelvic girdle + sacrum + coccyx = bony
pelvis – Ilium; Ischium and Pubis
2. Male vs. Female – Male: cavity is narrow; deep; less tilt;
heavier – Female: broad cavity; lighter; acetabula
farther apart
3. Female and Childbirth – True pelvis (inlet and outlet) important for
childbirth
Lower Limbs 1. Femur – Largest, longest, strongest bone in
the human body – Trochanters (thigh and buttock
muscles) – Epicondyles – Patella
2. Tibia and Fibula – Tibia: transfers weight of femur to
foot; distal tibia articulates with talus of foot; medial malleolus (ankle)
– Fibula: not weight bearing; muscular attachments
Foot1. Tarsus– (7) tarsal bones– “talus” – ankle bone;
“calcaneous” – heel– Cuboid, navicular and
cuneiform bones
2. Metatarsus and Phalanges– (14) phalanges