Midterm 2

Question 1

Osteoblast

Answer 1

Bone building cell

Question 2

Osteiod

Answer 2

The immature bone that is first formed. It contains the collagen fibers and proteins that promote calcium salt formation onto the collagen.

Question 3

Osteocytes

Answer 3

Mature Osteoblasts, Bone cells.

Question 4

Osteoclasts

Answer 4

Breaks down bone.

Question 5

Lacunae

Answer 5

empty space in bone, where osteocytes are located.

Question 6

Chondroblasts

Answer 6

Form cartilage

Question 7

Connective tissue

Answer 7

Bone, Blood, Dense regular connective tissue, areolar CT. Unifying characteristic- all form from mesenchyme.

Question 8

4 primary tissue types

Answer 8

epithelial, connective, muscle and neural.

Question 9

3 types of embryological origin

Answer 9

Mesoderm, Ectoderm, Endoderm

Question 10

Mesoderm

Answer 10

(middle) “everything else” Connective tissue, Wall of digestive and respiratory tracts, heart. ect.

Question 11

Ectoderm

Answer 11

Epidermis, hair nails and glands of skin. BRAIN and SPINAL CORD

Question 12

Endoderm

Answer 12

Epithelial lining and glands of the digestive and respiratory tracts.

Question 13

Fibroblasts

Answer 13

cell type found in tendons (dense regular connective tissues) and they are responsible for producing the collagen fibers.

Question 14

Fibroblasts

Answer 14

cell type found in tendons (dense regular connective tissues) and they are responsible for producing the collagen fibers.

Question 15

Osteons

Answer 15

the structural unit of compact bone. They make up the thick walls of long bone diaphyses and the most superficial compact bone collar (cortex) of long bone epiphyses.

Question 16

Trabeculae

Answer 16

the struts of spongy bone in the epiphyses and adjacent to the medullary cavity. They are more lightweight than dense compact bone (as evidenced by their many open spaces). In the epiphyses they transmit weight to the more dense compact bone of the outer diaphyseal cortex. They remodel very rapidly in response to signals

Question 17

Articular cartilage

Answer 17

cartilage on the end of long bones

Question 18

What is the difference between spongy bone and compact bone?

Answer 18

Spongy bone and compact bone are microscopically arranged differently. Spongy bone and compact bone are made of the same matrix material (1/3rd collagen, 2/3rds mineral), contain the same cellular populations (osteoblasts, osteoclasts, osteocytes, osteoprogenitor cells) and are both found in long bones. Microscopically, the matrix arranges itself as osteons in compact bone, but as non-osteon, irregular lamellae of trabeculae in spongy bone.

Question 19

lamella

Answer 19

a ring of osteoid secreted by osteocytes that eventually mineralizes and traps the osteocytes within pockets (lacunae).

Question 20

Hyaline cartilage

Answer 20

connective tissue that makes embryonic protoskeletons and articular cartilage.

Question 21

endosteum

Answer 21

is made of connective tissue cells, that can deposit or reabsorb bone from the internal aspect of the bone. During growth, the endosteum is particularly important to remodel bone from the inside. Without endosteal bone reabsorption, as bones grow wider overall, the bone would become too heavy. In other words, as bones grow wider (due to periosteal bone deposition), they maintain the same cortical bone thickness because of endosteal removal.

Question 22

periosteum

Answer 22

a double layered structure on the outside of all bones. The outermost layer is a fibrous connective tissue, the innermost layer (adjacent to the cortical bone) is a layer of osteoblasts, osteoclasts and osteogenic/osteoprogenitor cells.

Question 23

Appositional growth

Answer 23

occurs when the cartilage model also grows in thickness due to the addition of more extracellular matrix on the peripheral cartilage surface, which is accompanied by new chondroblasts that develop from the perichondrium.

Question 24

Diaphysis

Answer 24

The shaft of long bone.

Question 25

intramembranous bone formation

Answer 25

During intramembranous bone formation, mesenchymal cells in the mesenchyme differentiate to become osteoblasts. Types of bone formed - include the flat skull bones of the cranium, the clavicle and the mandible.

Question 26

Epiphysis

Answer 26

The end of long bone

Question 27

Endochondral bone formation

Answer 27

Formation of bone around Hyaline cartilage.

Question 28

Joint classifications (function)

Answer 28

synarthrotic, amphiarthrotic or diarthrotic

Question 29

Joint classification (material/structure)

Answer 29

cartilaginous, synovial or fibrous

Question 30

Synarthrotic joints

Answer 30

Little or no movement (Skull sutures)

Question 31

Amphiarthrotic

Answer 31

Slightly moveable ( intervertebral discs, pubic symphysis)

Question 32

Diathrotic

Answer 32

Freely moveable (shoulders, carpals/tarsals)

Question 33

Fiborous joints

Answer 33

collagen fibers spanning the space between bones.

Made of dense fibrous connective tissue (sutures, Syndesmosis, Gomphosis)

Question 34

Cartlaginous joints

Answer 34

2 bones bound to each other by cartilage Synchondrosis- connected by hyaline cartilage
Symphysis- connected by fibrocartilage (more flexible)

Question 35

Synovial joints

Answer 35

bones held together by joint capsule filled with synovial fluid ( shoulder, elbow, carpal joints, knee, tarsal joints)
Are all Diathrotic joints. (planar, hinge, pivot, saddle, condylar, Ball and socket.)

Question 36

Direct bone healing

Answer 36

the broken elements must be very close together and osteoblasts present at the site of injury deposit concentric lamellae around blood vessels.

Question 37

Indirect Bone healing

Answer 37

occurs when bone fragments are further apart. Initially, a large vascular response occurs, bringing cells and nutrients to the site of injury. Then, a temporary bridge (patch) forms. The temporary patch consists of cells and collagen fibers in a gelatinous, avascular matrix. The patch is then replaced by woven, trabecular bone but is later remodeled into mature bone.

Question 38

Epimysium

Answer 38

connective tissue layer surrounding whole muscle

Question 39

endomsyium

Answer 39

deep in the muscle, surrounding individual muscle cells, above the cell membrane.

Question 40

perimysium

Answer 40

surrounds bundles of muscle cells/fibers. These bundles are called fascicles and the connective tissue wrapper around them is in-between the fiber density of the endomysium and epimysium.

Question 41

sarcolemma

Answer 41

the cell membrane of a muscle cell - “sarco” means flesh (meat, muscle is meat) and “lemma” means husk or outer coat.

Question 42

Thin filament

Answer 42

Pulled by thick filament to produce muscle contractions. Made up of Actin, troponin, tropomyosin.

Question 43

Thick filament

Answer 43

Made of Myosin and Titin, Forms cross bridges with thin filaments to cause muscle contractions.