1. The Skeletal System Chapter 36 Section 1 Notes

2. Lecture Outline – The Skeletal System
PowerPoint Notes
textbook questions
Keys

3. Skeletal System Functions
Makes up body framework - gives body shape
Supports the body
Protects vital internal organs

4. Skeletal System Functions
Makes up body framework - gives body shape
Supports the body
Protects vital internal organs

5. Functions continued… Provides for movement Stores mineral reserves
Produces red blood cells

6. Bone Composition Bone is living tissue.
It is a solid network of cells and protein fibers surrounded by deposits of minerals.
Components:
32% Organic materials (collagen and bone cells)
43% Minerals (calcium and phosphorous)
25% Water

7. Bone Cells There are four main types of bone cells in bone tissue.
Osteogenic cells respond to traumas, such as fractures, by giving rise to osteoblasts and osteoclasts.
Osteoblasts (bone-forming cells) synthesize and secrete unmineralized ground substance and are found in areas of high metabolism within the bone.
Osteocytes are mature bone cells made from osteoblasts that have made bone tissue around themselves.
Osteoclasts are large cells that break down bone tissue. They are very important to bone growth, healing, and remodeling.

8. Skeletal Tissue 4 main types Compact bone Spongy bone Cartilage
Fibroblasts
spongy
compact
cartilage
fibroblasts
Ligament

9. Anatomy of a Typical Long Bone
Structure of Bone
Anatomy of a Typical Long Bone
Femur

10. Structure of bone
Spongy bone is the inside layer of compact bone that is actually quite strong but lacy in appearance and contains red marrow which produces blood cells.
Taking a closer look: A cross- section of the long bone.
Periosteum covers bone, is a place for tendon and ligament attachment, and brings blood, lymph vessels and nerves into the bone.
Compact bone is a dense layer of bone tissue composed of cylinders or tubes of mineral crystals and protein fibers, that give bone its strength.
Bone marrow (primarily yellow marrow) stores fat that serves as an energy reserve and contains blood vessels and nerve cells.
Copyright © 2003 Pearson Education, Inc., publishing as Benjamin Cummings

11. Structure of Bone
Haversian canal
Osteocytes are responsible for bone growth and changes in the shape of bone and can either deposit or absorb calcium salts
Here is another diagram
Just to help give you that visual to remember all of this!
Haversian canal are interconnected networks of tubes that blood vessels and nerves run through.
Blood vessels carry nourishment to the living bone tissue as well as removing wastes

12. Structure of Bone
Notice… Hyalin cartilage covers the ends of bones where they articulate (join) with other bones.
As adulthood is reached, the epiphyseal plate (growth plate) is replaced by bone and fuses, thus completing growth.

13. Structure of Bone { What parts do you remember? Let’s Quiz Ourselves!
Blood vessels
Bone marrow
Compact bone
Haversian canal
Osteocyte
Periosteum
Spongy bone 1 { 23 5 6 7 4 5 3 1 7 4 6 2

14. Structure of Bone
Bones of the skeleton contain a combination of spongy and compact bone.
Do you recognize the bone at the left?
What classification (type) of bone is it?
What type of bone marrow is found within the spaces of the spongy bone?
Skull Bone
A flat bone
Red Marrow

15. Bone Formation
Called Ossification- Process of producing bone from cartilage
________ is replaced by _________ which secrete ________deposits and then mature into __________(bone cells).
___________ break down bone and remove _________bone tissue when a bone is broken.
Cartilage x
osteoblasts
mineral
osteocytes
Osteoclasts
damaged

16. Bone Formation Growth in Length
The _______ plate (epiphyseal disc) is an area of _______ in the _____of long bones where bone _________ occurs.
growth
cartilage
ends
lengthening

17. Bone Formation Bone growth begins long before birth.
10 week fetus
Cartilage bone
of the skull
Intramembranous
ossification
produces the
roofing bones
Primary
centers of the
diaphyses
(skeleton of the
lower limb)
Future
hip bone
Bone growth begins long before birth.
The basic shape of a long bone, such as an arm bone, is first formed as cartilage

18. Bone Formation 12 week fetus 16 week fetus
Ossification begins to take place up to seven months before birth

19. Bone Formation
Babies are born with 350 bones, many are composed almost entirely of cartilage.
Latter the cartilage cells will be replaced by cells that form the bones. (ossification)
The SOFT SPOT of a babie’s skull will fuse around age , but growth of the skull continues until adulthood.
Long bones develop and grow through out childhood at the centers of ossification (growth plates)

20. Bone Formation Stages of Ossification
Between the ages of 16 and 25 years, all of the cartilage of the epiphyseal disc is replaced by bone. This is called closure of the epiphyseal disc, and the bone lengthening process stops. 

21. Bone Formation G R O W T H I N D

22. The adult skeleton contains _____ bones
Bones of the Skeleton
The adult skeleton contains _____ bones
206

23. Name That Bone Do you recognize these 22 bones? carpals clavicle11 21 22 20 19 12 18 15 16 17 13 14 10 9 8 6 5 4 3 2 1 7
Do you recognize these 22 bones?
carpals
clavicle
coccyx
femur
fibula
humerus
mandible
metacarpals
metatarsals
patella
phalanges
pelvis
radius
ribs
sacrum
scapula
skull
sternum
tarsals
tibia
ulna
vertebrae 9 6 16 19 8 4 12 7 14 17 18 1 2 3
1cranium, skull 2mandible 3clavicle 4sternum 5humerus 6rib 7vertebra 8pelvis 9radius 10ulna 11carpals 12metacarpals 13phalanges 14femur 15patella 16tibia 17fibula 18tarsals 19metatarsals 20phalanges 10 21 22 15 13 20 11 5

24. Axial and Appenicular Skeletons
Divisions of Skeleton
Axial and Appenicular Skeletons

25. Axial Skeleton
THE AXIAL SKELETON - CONSIST OF THE SKULL, VERTEBRAL COLUMN, AND THE RIB CAGE
Skull
Vertebral column
Rib cage (ribs + sternum)
Skull

26. Skull Bones * The Skull consists of 8 CRANIAL BONES + 13 FACIAL BONES
* The Ears consists of
6 BONES and
* Floating in the throat is 1 HYOID BONE
Inner Ear

27. Rib Cage Also called the Thoracic Cage 12 pairs of RIBS 1 STERNUM
7 true ribs
5 false ribs
2 floating ribs
1 STERNUM
(breastbone)

28. Vertebral Column The Vertebral Column (Spinal Column or Backbone)
7 CERVICAL (NECK) VERTEBRAE,
12 THORACIC
5 LUMBAR,
5 FUSED VERTEBRAE INTO 1 SACRUM,
4 SMALL FUSED VERTEBRAE INTO 1 COCCYX (YOUR TAIL BONE)

29. Appendicular Skeleton
THE APPENDICULAR SKELETON – consists of bones of the:
ARMS (upper limbs)
LEGS (lower limbs)
SHOULDER GIRDLE (pectoral girdle)
HIP GIRDLE (pelvic girdle)

30. Shoulder Girdles and Arms
The Shoulder girdle is also called the pectoral girdle
Consists of 4 bones
Upper limbs consist of 60 bones (the hands and wrist contain 54 separate bones).

31. Hip Girdles and Legs The hip girdle is also called the pelvic girdle
Consists of 2 bones
Lower limbs consist of 60 bones (the ankles and feet contain 52 separate bones)

32. Comparison of Skletons
The Human Skeleton is homologous to skeletons of other animals. Once you learn the bones in a human, you can identify the bones in other animals.
rat
cat
horse

33. Bone Classification by Shape
5 Types
Long
Short
Flat
Irregular
sesamoid

34. Shapes of Bones
Long bones are longer than they are wide and work as levers. The bones of the upper and lower extremities (ex. humerus, tibia, femur, ulna, metacarpals, etc.) are of this type.
Short bones are short, cube shaped, and found in the wrists and ankles.
Flat bones have broad surfaces for protection of organs and attachment of muscles (ex. cranial bones, ribs, and bones of hip and shoulder girdles).
Irregular bones are all others that do not fall into the previous categories. They have varied shapes, sizes, and surface features and include the bones of the vertebrae and a few in the skull.

35. Types of Bones
1.  The humerus and femur are examples of _______ bone.
2.  Tarsal and carpal bones are examples of _______ bone.
3.  Sternum and many skull bones are examples of ________bone.
4.  Vertebrae and the patella are examples of _______ bone.
long
short
flat
irregular

36. Joints JOINTS: WHERE TWO or MORE BONES MEET
Joints are responsible for keeping bones far enough apart so they do not rub against each other as they move, preventing damage.
At the same time, joints hold the bones in place.
Different joints permit different amounts of movement.
Joints are classified by the amount and type of movement they permit.

37. Classification of Joints
Three Main Types
Immovable- A fixed joint, one that allows no movement
bones of skull, pelvis, and sacrum
Slightly movable- joint that permits a small amount of restricted movement
between vertebrae, two bones of lower leg
Freely movable- Permit movement in one or more directions

38. Classification of Joints
Ribs
Classification of Joints
Immovable
bones of skull,
pelvis, and sacrum
Slightly movable
between vertebrae,
two bones of lower leg
Vertebra
Tibia and Fibula
Pelvis
skull

39. Freely Movable Joints TYPES OF FREELY MOVABLE JOINTS
A. BALL AND SOCKET JOINT – Permits circular movement - the widest range of movement.
SHOULDER Joint- which enables you to move your arm up, down, forward and backward, as well as to rotate it in a complete circle.
HIP Joint- same range of motion.

40. Types of Freely Movable Joints Continued
B. HINGED JOINT - Permits a back and-forth motion.
The Knee- enables your leg to flex and extend.
The Elbow -allows you to move your forearm forward and backward.
The Phalanges
C. PIVOT JOINT - Permits rotation of one bone around another.
The elbow enables your hand to turn over. (radius rotates around ulna)
It also allows you to turn your head from side to side. (atlas rotates around axis)

41. Types of Freely Movable Joints Continued
D. GLIDING JOINT - Permits a sliding motion of one bone over another.
Found at ends of the collarbones,
between wrist bones,
and between anklebones.
Click Here
E. SADDLE JOINT- Permits movement in two planes.
This type of joint is found at the base of the thumb
Click on skeleton to link to this ^ site for an interactive animation

42. Anatomy of a Joint Structures of a freely movable joint
2 or more bones
Cartilage
Joint capsule
Synovial membrane
Synovial fluid
Fat
Bursa
Meniscus
Ligaments
Tendons

43. Anatomy of a Joint
Cartilage - at the joint, the bones are covered with cartilage, which is wear-resistant and helps reduce the friction of movement.
Joint capsule- is a thick, tough layer that envelops the joint cavity forming a membrane or sac that adheres firmly to the periosteum of the articulating bones

44. Anatomy of a Joint
Synovial membrane - a tissue that lines the joint and seals it into a joint capsule. The synovial membrane secretes synovial fluid.
Synovial fluid - a clear, sticky fluid secreted by the synovial membrane to lubricate the joint.

45. Anatomy of a Joint Fat- Helps pad and cushion the joint.
Bursa- fluid-filled sac between adjacent structures such as ligaments or bones which help reduce friction in a joint, cushion it, and absorb shock.
Meniscus- wedge shaped cartilage, curved like the letter "C" at the inside and outside of each knee. A strong stabilizing tissue, helps the knee joint carry weight, and glide and turn in many directions. It also keeps your femur and tibia from grinding against each other.

46. Anatomy of a Joint
ligaments - tough, elastic bands of connective tissue
surround the joint to give support and limit the joint's movement.
Attach bone to bone
tendons – another type of tough connective tissue
on each side of a joint attached to muscles that control movement of the joint.
Attach muscle to bone
Knee Joint

47. Skeletal Disorders Fractures
A broken bone is known as a fracture. This can simply be a crack or buckle in the structure of the bone, or a complete break, producing two or more fragments.

48. Skeletal Disorders Bone Fracture Repair
The repair of bone fractures is similar to embryonic bone formation.

49. Skeletal Disorders Arthritis Arthritis- inflammation of the joints
Consists of more than different conditions
The common denominator for all these conditions is joint pain
Osteoarthritis- nick-named “wear and tear” arthritis
Rheumatoid arthritis is one of the most crippling forms of arthritis. It is characterized by chronic inflammation of the lining of joints.

50. Skeletal Disorders Osteoporosis
Osteoporosis- literally means "porous bones“
Occurs when a body's blood calcium level is low and calcium from bones is dissolved into the blood to maintain a proper balance.
Over time, bone mass and bone strength decrease. As a result, bones become dotted with pits and pores, weak and fragile, and break easily.
Other factors besides age can lead to osteoporosis, such as a diet low in calcium and protein, a lack of vitamin D, smoking, excessive alcohol drinking, and insufficient weight-bearing exercises to stress the bones.