1. The document discusses the functions and components of bones in the human body. It describes how bones provide structure, protection, movement, mineral storage, blood cell production, and triglyceride storage. 2. The main components of bones are described including the skull, vertebral column, ribs, sternum, and bones of the upper and lower limbs. 3. The types of bones - long, short, flat, irregular, and sesamoid - are defined along with examples of each type.

1. By
Dr. Noura El Tahawy
http://www.slideshare.net/nmohmed

2. Functions
Support
Protection
Assistance in movement
Mineral homeostasis
Blood cell production
Triglycerides storage

3. Functions of bones
1. Bones form the skeleton which is the framework of the body.
2. The skeleton supports the softer tissues and provides points of attachment
for most skeletal muscles.
3. The skeleton provides mechanical protection for many of the body's
internal organs, reducing risk of injury to them. It forms boundaries of
cranial, thoracic and pelvic cavities. Thus it protects the brain, lungs, heart
etc.
4. Bones permit movement of the body as a whole or part of the body, by
formation of joints, which are moved by muscles.
5. Bone tissues store several minerals, including calcium and phosphorus.
When required, bone releases minerals into the blood facilitating and
maintaining the balance of minerals in the body.
6. Bone contains red bone marrow in which blood cells develop.
7. Bone acts as an important chemical reserve. With advancing age, some
bone marrow changes from red bone marrow to yellow bone marrow
which consists mainly of adipose cells and a few blood cells.

5. Components
Skull
Vertebral column
Auditory ossicles
Hyoid
Ribs
Sternum

8. Components
Upper limb bones
Pectoral (shoulder) girdle
Lower limb bones
Hip girdle

10. Types of bones
Long bone
Short bone
Flat bone
Irregular bone
Seasamoid bone

11. Types of bones

12. Long bone
Greater length than width
Mostly compact bone tissue
Curved
Vary in size
Includes:
Femur Ulna
Tibia Radius
Fibula Phalanges
Humerus

13. Long bone: Femur

15. Forms of bone

16. Short bones
Cube shaped
Equal lenghth and width
Mostly spongy, except on surface it is compact
Includes:
carpal bone (except pisiform)
tarsal bones (except calcaneus)

17. Flat bones
Thin
2 layers of compact surrounding a spongy layer
Large areas for muscle attachment
Includes:
Cranial bones
Sternum
Ribs
Scapulae

18. Irregular bones
Complex shape
Amount of spongy and compact varies
Includes:
Vertebrae
Hip bone
Certain facial bones
Calcaneus

19. Sesamoid bones
Develop in certain muscles tendons
Protect the tendons from excessive wear

22. Structure of bone
Diaphysis
Epiphysis
Metaphysis
Articular cartilage
Periosteum
Medullary cavity
Endosteum

25. Structure of
bone:

26. Spongy bone tissue

27. Types of ossification
By
DR. Noura El Tahawy

28. Bone formation
Intramembranous ossification
(flat bones)
Endochondral ossification
(long bones)

29. Bone Growth & Remodeling
Growth
Appositional Growth = widening of bone
Bone tissue added on surface by osteoblasts of the periosteum
Medullary cavity maintained by osteoclasts
Lengthening of Bone
Epiphyseal plates enlarge by chondroblasts
Matrix calcifies (chondrocytes die and disintegrate)
Bone tissue replaces cartilage on diaphysis side

30. Endochondral ossification

31. Endochondral ossification
Endochondral ossification is the gradual replacement of
cartilage by bone during development. This is responsible
for formation of most of the skeleton. Osteoblasts arise in
regions of cartilage called ossification centers. They
develop into osteocytes, which are mature bone cells,
embedded in the calcified (hardened) part of the bone
known as the matrix.

32. Intramembranous ossification
Intramembranous ossification is the transformation of the
mesenchyme, embryonic cells, into bone. During early
development, the embryo consists of three primary cell layers,
ectoderm on the outside, mesoderm in the middle and
endoderm on the inside. Mesenchyme cells constitute part of
the embryo's mesoderm and develop into connective tissue
such as bone and blood. The bones of the skull derive directly
from mesenchyme cells by intramembranous ossification.

33. Most bones arise from a combination of intramembranous
and endochondral ossification. Mesenchyme cells develop
into chondroblasts and increase in number by cell division.
Chondroblasts enlarge and excrete a matrix which hardens due
to presence of inorganic minerals. Chambers form within the
matrix and osteoblasts and blood-forming cells enter these
chambers. The osteoblasts then secret minerals to form the
bone matrix.

35. Vertebral Column

36. Vertebral Column

38. Vertebra

39. Typical vertebra

42. Skull

43. Skull

44. Ribs
Sternum

46. Upper limb bones
Humerus
Ulna and radius
Carpal bones
1- Scaphoid 2- Lunate
3- Triquetrum 4- Pisiform
5- Trapezium 6- Trapezoid
7- Capitate 8- Hamate
Metacapals
phalanges

47. Pectoral girdle
Clavicle
Scapulae

50. Bones of the upper
limb

53. Lower limb bones
Femur
Tibia
Fibula
Tarsal bones
1- Talus 2- Calcaneum
3- Navicular 4- Cuboid
5- Medial cuniform
6- Intermediate cuniform
7- Distal cuniform
Metatarasals
Phalanges

54. Hip girdle
Hip bone
1- ilium
2- pubis
3- sacrum

59. Bones of the lower limb

60. Bones of the lower limb

61. Bones of the foot

62. Bones of the foot

63. Thanks
http://www.slideshare.net/nmohmed