Skeletal System (Exam 2) Flashcards Preview

Spring of 2012 > Skeletal System (Exam 2) > Flashcards

Flashcards in Skeletal System (Exam 2) Deck (55)
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0
Q

Function: protection

A

Skull protects the brain
Vertebrae protect the spinal cord
Rib Cage protects the thoracic cavity viscera

1
Q

Function: storage

A

Bones are the major support tissue of the body
Cartilage- firm yet flexible support
Ligaments- attach to bones and hold them together

2
Q

Function: storage

A

Ca+2- needed for blood clotting and for electrical signaling in the heart
Phosphorous- needed for ATP synthesis and DNA production

3
Q

Function: blood cell production

A

Bone marrow- location of the rbc, WBC, and platelet production

4
Q

Functions

A
Support
Protection
Movement
Storage
Blood cell production
5
Q

Cartilage

A

Consists of special cells called chondroblasts that produce new cartilage matrix

6
Q

Chondrocyte

A

When the secreted matrix surrounds the condroblast

It matures

7
Q

Lacunae

A

The space a chondrocyte occupies

8
Q

Perichandrium

A

A double layered connective tissue sheath that covers cartilage

Outer layer- dense regular connective tissue with fibroblasts
Inner layer- made mostly of chondroblasts

9
Q

Appositional growth

A

Growth from the outside

Chondroblasts lay down new matrix on the outside of the tissue

10
Q

Interstitial growth

A

Growth from the inside

Inner chondrocytes rapidly divide, expanding the cartilage from within

11
Q

General bone characteristics

A

206 named bones
Each bone is an organ
Made of living tissue (can grow and repair)

12
Q

Axial skeleton

A

Function: protection and support

Skull, rib cage, vertebral column

13
Q

Appendicular skeleton

A

Function: movement

Upper and lower limbs, shoulder and pelvic girdles

14
Q

4 bone shapes

A

Long
Short
Flat
Irregular

15
Q

Long bones

A

Longer than they are wide

Most bones of the upper and lower limbs

16
Q

Short bones

A

A wide as they are long

Bones of the wrist and ankle

17
Q

Flat bones

A

Thin, flat, usually curved

Some skull bones, sternum, ribs, scapula

18
Q

Irregular bones

A

Odd shaped

Vertebrae, patella (sesamoid bone)

19
Q

Long bone structure

A
Diaphysis
Epiphysis
Epiphyseal plate
Medullary cavity
Periosteum
Endosteum
20
Q

Diaphysis

A

Shaft that forms the long axis

Formed mostly of compact bone

21
Q

Epiphysis

A

Knobs on the end of long bones
Composed mostly of spongy/cancellous bone
Outer covering of compact bone

22
Q

Epiphyseal plate

A

Hyaline cartilage between the epiphysis and the diaphysis
Area of growth
At the end of the growth it is transformed into bone and is called the epiphyseal line

23
Q

Medullary cavity

A

In the diaphysis of the long bone
Children- contains red marrow
Adults- contains yellow marrow

24
Q

Periosteum

A

CT membrane covering the outer surface of bone
Outermost: dense, irregular CT
Innermost: osteoblasts, osteoclots
Sharpey’s fibers

25
Q

Osteoblast

A

Bone forming cell

26
Q

Osteoclot

A

Bone resorbing cell

27
Q

Sharpey’s fibers

A

Secure tendons and ligaments to periosteum

28
Q

Endosteum

A

CT membrane lining inner bone surfaces

29
Q

Flat bone structure

A

Usually no epiphysis or diaphysis
Contains spongy bone called diploe
Compact bone on the outer surface

30
Q

Short and irregular bone structure

A

Spongy bone center (trabeculae and marrow)

Compact one on the outer surface

31
Q

Osteon

A

The structural unit of Compact bone

32
Q

Lamellae

A

Circular layers of the bone matrix

Compact bone

33
Q

Haversian canal

A

Passage way for blood vessels and nerves

Compact bone

34
Q

Canaliculi

A

Small canals that connect the lamellae to each other and to the central haversian canal

Allows nutrient and waste exchange for the osteocytes

Compact bone

35
Q

Ossification (osteogenesis)

A

Bone development

Begins 8 weeks after conception

36
Q

Long bones at birth……

A

Are well ossified except for the epiphyseal plate

Complete ossification at the end of the growth period

37
Q

Bones of the skull don’t begin to ossify until……

A

The 10th week of gestation

Not completely ossified at birth
Final ossification at 2 years of age

38
Q

Fontanels

A

Fibrous membranes holding the bones of the skull together before ossification

39
Q

Bone growth

A

Happens in length
New bone is formed on the surface of cartilage
Occurs at the epiphyseal plate

40
Q

4 zones of the epiphyseal plate

A

Zone of resting cartilage
Zone of proliferation
Zone of hypertrophy
Zone of calcification

41
Q

Zone of resting cartilage

A

Nearest to the epiphysis

Contains randomly arranged chondrocytes that are slowly dividing

42
Q

Zone of proliferation

A

2nd zone
Chondrocytes producing new cartilage through interstitial cartilage growth
Rapid division

43
Q

Zone of hypertrophy

A

3rd

Chondrocytes produced in zone 2 (proliferation) mature and enlarge

44
Q

Zone of calcification

A

Consists of cartilage matrix mineralized by Ca+2
Hypertrophied chondrocytes die
Blood vessels inner ate the area

CT surrounding blood vessels contain osteoblasts
They deposit new bone matrix on the surface of the calcified cartilage (appositional growth)

45
Q

Factors affecting bone growth

A

Nutrition

Hormones

46
Q

Vitamin D

A

Needed for absorption of Ca+2 from the small intestine

Deficiency in children can lead to rickets
Adults with the inability to metabolize vitamin D can develop osteomalacia

47
Q

Rickets

A

A disease resulting from reduced mineralization of the bone matrix

Causes bones to “bow”

48
Q

Osteomalacia

A

Softening of the bones as a result of Ca+2 depletion

49
Q

Vitamin C

A

Necessary for collagen synthesis by osteoblasts

Deficiency can result in scurvy

50
Q

Scurvy

A

Characterized by ulceration and hemorrhage of skin because of lack of normal collagen in CT

51
Q

Hormone at regulate the exchange of calcium between blood and bone

A

Calcitonin

Parathyroid hormone

52
Q

Calcitonin

A

Synthesized and secreted by the thyroid gland
Promotes the incorporation of Ca+2 into bone from blood

Sensitive to estrogen levels
Lots of estrogen=lots of calcitonin release=lots of Ca+2 incorporated into the bone
Menopausal women may develop osteoporosis

53
Q

Osteoporosis

A

Brittle bones due to a decrease in Ca+2 deposition

54
Q

Parathyroid hormone

A

Synthesized and secreted by the parathyroid gland
Signal for release is low plasma calcium levels
Mobilizes Ca+2 from the bone into the blood

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