Chapt11 Lecture 13ed Pt 3

Human Biology Sylvia S. Mader Michael Windelspecht

Chapter 11 Skeletal System Lecture Outline Part 3

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

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11.3 Bones of the Appendicular Skeleton

Skeletal remains •

Characteristics to be determined –

Age is approximated through dentition, studying areas of bone ossification, and joint condition.

–

For gender, it is best to use the pelvic bone, but the thickness of long bones or skull characteristics may also be used.

–

Ethnicity is difficult to tell, but skull characteristics are most useful. 2

11.4 Articulations

Types of joints (where bones meet bones) • __________ – usually immovable such as the sutures between cranial bones

• ______________ – tend to be slightly movable such as the intervertebral disks • __________ – freely movable joints such as the ball-and-socket hip and shoulder joints, and the hinge knee and elbow joints 3

11.4 Articulations

Anatomy of a synovial joint Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

a: © Gerard Vandystadt/Photo Researchers, Inc. bursae joint cavity filled with synovial fluid

articular cartilage meniscus

meniscus

ligament ligament

head of humerus

scapula

b. Generalized synovial joint

ulna

humerus c. Ball-and-socket joint

a. A gymnast depends on flexible joints.

Figure 11.9 The structure of a synovial joint.

d. Hinge joint

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11.4 Articulations

Summary of synovial joints movements • Flexion – __________ in joint angle • Extension – _________ in joint angle

• __________ – body part moves toward midline • __________ – body part moves away from midline

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11.4 Articulations

Summary of synovial joints movements • Rotation – body part moves around its own axis • Supination – hand faces anterior or downward • Pronation – hand faces posterior or downward

• Circumduction – body part moves so that a cone shape is outlined 6

11.4 Articulations

Summary of synovial joints movements • Inversion – sole of foot turns inward • Eversion – sole of foot turns outward

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11.4 Articulations

Visualizing synovial joints movements Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Rotation: Body part moves around its own axis.

extension flexion

abduction

flexion extension

abduction

Inversion: Sole of foot turns inward.

adduction

flexion adduction

extension

abduction adduction

Flexion: Joint angle decreases. a.

Extension: Joint angle increases.

Adduction: Body part moves toward midline.

Supination: Hand faces anterior or downward. Pronation: Hand faces posterior or downward.

Abduction: Body part moves away from midline.

b.

c.

Circumduction: Body part moves so that a cone shape is outlined.

Eversion: Sole of foot turns outward. d.

Figure 11.10 Synovial joints allow for a variety of movement.

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11.5 Bone Growth and Homeostasis

What are the important cells in bone growth, remodeling, and repair? • Osteoblasts – bone-forming cells • Osteocytes – mature bone cells that maintain bone structure derived from osteoblasts • Osteoclasts – bone-absorbing cells • Chondroytes – cartilage-forming cells 9

11.5 Bone Growth and Homeostasis

How does bone develop? •

Ossification is the formation of bone in 2 distinct ways.:

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_____________________ – bone development between sheets of fibrous connective tissue; used in flat bones

2.

_____________________ – cartilage is replaced by bone; used by most bones

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