Skeletal System

Question 1

Skeletal system

Answer 1

An organ system
Consists of bones, cartilage, tendons( muscle to bone) and ligaments (bone to bone)

Question 2

Functions of skeletal system

Answer 2

•Protection
•mineral storage and homeostasis
•Hematopoiesis (in red bone marrow) formation of blood cells
• Fat Storage( in yellow bone marrow)
• Movement
• support

Question 3

Classifications of Bones by shape

Answer 3

Long, short, flat, irregular, Sesamoid

Question 4

Long bone

Answer 4

Longer than wide; knobby ends
Found in arms & legs; fingers & toes

Question 5

Short bone

Answer 5

About equal length & width; rock shaped
Found in wrists and ankles

Question 6

Flat Bone

Answer 6

Thin, may be curved
Found in skull, rib cage & hips

Question 7

Irregular bone

Answer 7

Comped shape; don’t fit other categories

Ex: vertebrae, ethmoid& sphenoid bones(skull)

Question 8

Sesamoid bone

Answer 8

Looks like a short bone
Form in tendons in response to mechanical stress

Ex: patella (kneecap)

Question 9

Diaphysis of long bone

Answer 9

Bone shaft (long middle part)

Question 10

Epiphysis of long bone

Answer 10

Knobby ends

Question 11

Articular Carttilage of long bone

Answer 11

Caps the ends

Question 12

Epiphyseal line of long bone

Answer 12

Remnants of growth plate (epiphyseal plate)

Question 13

Bone texture of long bone

Answer 13

Compact/ solid
Spongy

Question 14

Medullary cavity of long bone

Answer 14

Hollow middle; contains red bone marrow (children) or yellow bone marrow (adults)

Question 15

Endosteum of long bone

Answer 15

Inner lining of bone

Question 16

Periosteum of long bone

Answer 16

Tough outer covering of bone

Question 17

Bone remodeling

Answer 17

20% of skeleton is replaced each year
In healthy adult bone, osteoblasts and osteoclast work at the same rate.

Question 18

Conditions that tip the balance of bone remodeling

Answer 18

Mechanical stress, hormones, and diet

Question 19

Bone cells

Answer 19

Osteoblasts, osteocytes, osteoclastS

Question 20

Osteoblast

Answer 20

Build bone- becomes trapped➡️ become osteocytes

Question 21

Osteocytes

Answer 21

Mature bone cells
Formally osteoblasts

Question 22

Osteoclasts

Answer 22

Breakdown bone

Question 23

Osteon

Answer 23

Basic unit of compact bone

Looks like tree trunk

Question 24

Central canal

Answer 24

How’s his blood vessels and nerves: parallel to length of bone

Question 25

Lamellae

Answer 25

Layers of solid bone around central canal Looks like rings of tree truck

Question 26

Osteocytes

Answer 26

Mature bone cells Looks like roaches

Question 27

Lacunae

Answer 27

Pockets that the osteocytes sit in

Question 28

Canaliculi

Answer 28

Canals that the osteocytes project cellular extensions (“arms”) through for communication and diffusion of nutrients.

Question 29

Perforating Canal

Answer 29

Houses, blood vessels and nerves perpendicular to the length of the bone

Question 30

Spongy bone structure

Answer 30

No osteons Trabeculae structure; trabecular= solid part of “sponge” Still has osteocytes in lacunae Bone marrow fills open space in “sponge” Always surrounds around the compact bone

Question 31

Cartilage CT Components

Answer 31

1. Cells - chondroblasts(build cartilage) chondrocytes (mature cartilage cells) 2. Protein fibers: collagen &/or elastic 3. Ground substance: rubbery

Question 32

Hyaline cartilage

Answer 32

(Firm/strong) Articular cartilage (end of long bones) Costal cartilage (rib cage) Fetal skeleton and growth plates Nose Trachea (windpipes)

Question 33

Fibrocartilage

Answer 33

(Weight bearing) Intervertebral discs Pubic symphysis Meniscus (knee)

Question 34

Elastic Cartilage

Answer 34

(Springy) Ear Epiglottis (part of voice box)

Question 35

Bone formation

Answer 35

Called Ossification or osteogenesis Begins in embryo @8-12 wks Completed by age 7

Question 36

Two types of ossification

Answer 36

Intramembranous ossification- forms flat bones of skull &clavicle Endochondral ossification- forms all bones below head (expect clavicle)

Question 37

Interstitial Growth

Answer 37

Bone growth in length - epiphyseal plates (childhood)

Question 38

Appositional growth

Answer 38

Bone growth in width (adulthood) Influenced by several factors.