CHAPTER 5 - INTRODUCTION TO THE SKELETAL SYSTEM

Ace your homework & exams now with Quizwiz!

What is in central canal?

contains blood vessels and nerves

Before 6 weeks of development, the skeleton is _________

hyaline cartilage

What is flat bone? Give examples

thin small bone Cranial bones Sternum Ribs Scapula

What happens during phase 2?

- Blood vessels grow around the edges of the cartilage - Perichondrium converts into periosteum - Formation of bone collar: thin layer of compact bone around the shaft of cartilage

What is a process?

bumpy projection

What happens during phase 7?

- Decrease in rate of epiphyseal cartilage enlargement - Increase if rate of osteoblast activity - Epiphyseal closure: epiphyseal cartilage gets narrower and narrower, eventually disappears - Articular cartilage forms

What happens during phase 6?

- Epiphyses filled with spongy bone - CYTES WANT TO GO SIDE TO SIDE - Formation of epiphyseal cartilage • Between epiphysis and diaphysis • Within metaphysis

What happens during phase 3?

- Increased blood supply - Primary ossification center • Cartilaginous matrix is replaced by spongy bone produced by osteoblasts

What happens during phase 5?

- Secondary ossification • Migration of capillaries and osteoblasts into epiphyses centers • Varies from: bone to bone, individual to individual

What happens during phase 4?

- Shaft filled with spongy bone - Osteoclasts create medullary cavity - Cartilage of metaphysis invaded by osteoblasts: production of bone columns - Further growth: increase in length, increased diameter

What are the first steps of endochondral ossification?

1-4: initiation of ossification in developing bone

Collagen fibers make up how much of the bone matrix?

1/3

What is the normal homeostasis level of blood/calcium?

100mg/100ml

Bone cells only contribute to how much of the bone mass?

2%

Calcium phosphate makes up how much of the bones mass?

2/3

What are the last steps of endochondral ossification?

5-7: increasing length of developing bone

What vitamins are essential in bone remodeling?

A C D

What is the skeletal system made up of?

Bones (osseous tissue) Connective Tissue (cartilages, ligaments)

What is a short bone? Give examples

Box like in appearance Carpals Tarsals

What are essential nutrients in bone remodeling?

Calcium Phosphorus Magnesium Sodium

________ is a type of dense connective tissue that is often found in joints to reduce friction. _________ is a type of fibrous connective tissue which attaches a bone to another bone.

Cartilage; ligament

What is found inside of an osteon?

Central canal Canaculi Osteocytes Lacunae Lamallae

What happens during phase 1?

Chondrocytes near the center of the diaphysis increase in size Chondrocytes die and disintegrate due to lack of nutrients Formation of cavities within the cartilage

What are factors that affect bone remodeling?

Diet Body resources: hormones

What is canaliculi?

Hairlike canals that connect lacunae to each other and the central canal

What is a pneumatized bone? Give an example

Have little air pockets, ethmoid bone

What does calcium phosphate eventually convert into?

Hydroapatite crystals

What are osteoprogenitor cells?

Mesenchymal stem cells that divide to produce osteoblasts

Where is bone added to during endochondral ossification?

Metaphysis

What are the cells are in charge of bone resorption?

Osteoclasts

What is the compact bone consisted of?

Osteons

What happens when the calcium is too low in the blood?

Parathyroid gland releases PTH Stimulates calcium release from bones (resorption) Stimulates calcium uptake in the kidneys Increases calcium uptake in the intestines Blood calcium level rises

The outside lining of bone that helps it attach to fascia and circulatory components is the

Periosteum

What is the correct order of events for bone remodeling?

Resting > Resorption > Reversal > Matrix deposition > Mineralization

What is the function of an osteoblast?

Secrete osteoid and build bone

What is the structure of the bone?

Supporting connective tissue Specialized cells

What happens when calcium is too high in the blood?

Thyroid gland releases calcitonin Stimulates calcium deposition in the bones Reduces kidney uptake Blood calcium level declines to set point

What is an irregular bone? Give examples

Weird shape Vertebrae Hip bones Temporal Sphenoid Some facial bones

What is a fissure?

a long, deep sulcus

what is a turbercle?

a small, rounded projection

What is the fascia?

a thin sheath of fibrous tissue enclosing a muscle or other organ

When does the secondary ossification center develop?

after birth

What is osteogenesis?

bone formation

What is solid matrix?

calcium salts around calcium fibers that are hard

What is another name for spongy bone?

cancellous or trabecular bone

What are chondrocytes?

cartilage cells

Stem cells differentiate into what during ossification?

chondroblasts

What forms the cartilaginous bone model?

chondroblasts

What is a foramen?

circular hole or passageway

What are the two types of osseous tissue?

compact bone and spongy bone

What is another name for compact bone?

cortical bone

What is calcification?

deposition of calcium salts

What is the inner lining of the bone called?

endosteum

What is the epiphysis of a long bone? What does it contain?

ends of bone MAINLY SPONGY BONE consists of red marrow

Where is hyaline cartilage found?

ends of bones, nose or ears

In an adult, the epiphysis is separated from the diaphysis by the:

epiphyseal line

Where is the secondary bone centers located?

epiphysis

When does endochondral ossification begin and end?

fetal stage until about age 20

What is a sesamoid bone? Give an example

found in joints Patella

What is an osteoblast?

immature bone cell

How is spongy bone arranged?

in parallel struts, trabeculae, thats what makes the bones lightweight

What is intramembranous ossification? What is it derived from?

involved in the development of clavicle, mandible, skull and face mesenchyme during embryonic periodxf

Where is cartilage found?

joints rib cage ear nose throat

What is a long bone? Give examples

long, have epiphysis, diaphysis, and metaphysis Femur Tibira Fibula Radius Clavicle MetaC MetaT Phalanges Humerus

What are osteocytes?

mature bone cells they release calcium ions position salts in the surrounding matrix

What does the endosteum line?

medullary cavity

What is reversal?

mononuclear cells soothing cut bone

What is resting?

no modeling

When does intramembranous ossification occur?

occurs during embryonic period and into the fetal period

How thick is the endosteum?

one cell thick

What is bone remodeling?

ongoing replacement of old bone tissue by new bone tissue

What is a canal/meatus?

opening a bone that is elongated into a tunnel-like passage through the bone

What is matrix deposition?

osteoblasts released into the fluid matrix

What is the function of an osteoclast?

osteoclasts are involved in bone reabsorption (breaking down bone)

What is resoprtion?

osteoclasts eat away at the bone

The functional unit of bone is known as:

osteon

What is the outer lining of the bone called?

periosteum

What is ossification?

process of bone formation

What is the function of the periosteum?

protection attaches to the fascia attachment site for circulatory and nervous supply

What is the function of an osteocyte?

provide nutrients and keep tissue alive

What osteolysis?

removing bone tissue

What is endochondral ossification?

replacement of cartilage by bone in limbs, vertebrae and hips

What is lamellae?

rings around the central canal, sites of lacunae

What is a tuberosity?

rough projection

What is a condyle?

rounded articular projection

What is the diaphysis? What does it contain

shaft of a long bone the medullary cavity which contains yellow/red marrow

What is a fossa?

shallow depression

What is lacunae?

small cavities that contain osteocytes

What is a sutural bone or wormion?

small flat bones, not everybody has, found in between sutures

What is a facet?

smooth, nearly flat articular surface

What are the functions of the skeletal system?

support, protection, movement, storage of minerals, blood cell formation

What is the primary difference in growth from primary to secondary bone centers?

the timing before birth the bone growth occurs at the primary ossification center after birth bone growth occurs at the secondary ossification center

What is mineralization?

trapping of osteoblasts and subsequent change into osteocytes

What are osteoclasts?

very big cells with multiple nuclei release calcium ions

What is the metaphysis?

where diaphysis and epiphysis meet


Related study sets

AP Human Geography- Unit 6 AP Classroom MCQ

View Set

Mental Health Nursing Chapter 26: Children and Adolescents

View Set

Chapter 1: What are the challenges in ethnographic fieldwork, and how is ethnographic research changing?

View Set

World History Study Guide Review

View Set