What are the 5 types of connective tissue?
Connective Tissue Proper
- Loose Connective Tissue
- Dense Connective Tissue
Where do you find hyaline cartliage?
Articular cartilage (found at joints)
Where do you find elastic cartilage?
Auricle of the ear
Epiglottis (Determines what tube something goes down from your mouth)
What are the characteristics of cartilage?
Semirigid, weaker than bone.
Flexible and resilient due to elastic fibers and water content.
Avascular (recieves nutrient supply through diffusion.
What are the functions of cartilage?
Support soft tissues
Articular surfaces for joints
Provide a model for endochondral bone formation (making bone from cartilage)
What are the functions of cartilage?
Support of soft tissues
Articular surfaces for joints
Provide a model for endochondral (endo=inside/within, chondral= cartilage) bone formation. (Making bone from cartilage)
Describe the structure of cartilage.
Chondroblasts produce the matrix of the cartilage. Once they become encased within the matrix they have produced and secreted, the cells are called chondrocytes and occupy small spaces called lacunae.
Cartilage has an extracellular matrix.
Perichondrium surrounds pieces of cartilage.
What is perichondrium? What does it provide to the cartilage?
Perichondrium is dense connective tissue.
It provides mechanical support and protection.
What type of extracellular matrix does bone have?
Calcified extracellular matrix. (Calcium phosphate)
What are the functions of bone?
Support and protect
Storage of minerals and energy reserves
How do bones protect the body?
They protect vital organs from injury and trauma.
e.g. cranial bones, rib cage, vertebrae, pelvis
What is hemopoiesis (hematopoiesis)?
Hemo = blood, poiesis = creation/formation
Red bone marrow (making blood)
How do the bones assist in the storage of minerals and energy reserves?
Storage: Calcium phosphate
Energy: Yellow bone marrow (yellow because it contains fat)
Who has exclusively red bone marrow? Why?
Children, because they are growing and need to create more blood.
Who has yellow bone marrow? Why?
Adults, because they've stopped growing and start to store fat in their marrow.
What are some examples of long bones?
Humerus, radius, ulna, metacarpals, phalanges, femur, tibia, fibula, metatarsals
What are the characteristics of short bones?
Length nearly equal to width
Covered by compact bone
Interior is mostly spongy bone
What are some examples of short bones?
Carpals, tarsals, sesamoid bones (bones you aren't born with e.g. patella)
What are the characteristics of flat bones?
Flat, thin surfaces
Roughly parallel surfaces of compact bone with a layer of internally placed spongy bone.
What is the epiphyseal line made of?
Bone that replaces the epiphyseal plate when a person stops growing.
In a long bone, where is the articular cartilage?
Hyaline cartilage covering the ends of bones within a joint.
In a long bone, where is the medullary cavity?
The middle of the bone. Medulla = middle, cavity = hollowed out
What does the medullary cavity contain?
Contains yellow marrow in adults and red marrow in children.
In a long bone, where and what is the endosteum?
Layer of cells lining the spongy bone and medullary cavity. (The first layer of cells inside the bone)
In a long bone where and what are the nutrient foramina?
They contain the nutrient artery. Blood vessel travels through the nutrient foramen.
What are the stem cells of bones called?
Osteoprogenitor cells (bone stem cells)
Osteo = bone, pro = before, genitor = creation
How do osteoblasts build bone?
They secrete osteoid (organic part of bone matrix).
They take calcium from the blood stream and make the bone thicker. They decrease blood calcium.
What are the characteristics of compact bone (cortical bone)?
Solid, relatively dense
Lined by periosteum
Found in the superficial regions of bone
Contains osteons (functional unit of bone).
What are the characteristics of spongy bone?
Lined by endosteum
Found in deeper regions of bone
Where and what is the central (Haversian) canal in the osteon?
Cylindrical channel that lies in the center of the osteon and runs parallel to it. Blood vessels and nerves that supply the bone run through it.
Where and what are the concentric lamellae in the osteon?
Concentric rings of osseous connective tissue that surround the central canal.
Where are the osteocytes in the osteon?
Mature bone cells housed in lacunae found between adjacent concentric lamellae.
Where and what are the lacunae in the osteon?
Cavities which house the osteocytes. Found between adjacent concentric lamellae.
Where are what are the canaliculi in the osteon?
Connect neighboring lacunae. Allow nutrients, minerals, gases, and wastes to travel between the central canal and osteocytes.
Where and what are the perforating (Volkmann's) canals?
Connect blood and nerve supply to central canal. Perpendicular to central canal.
What and where are parallel lamellae in the trabeculae?
They are the concentric lamellae of tribeculae.
What structures provide nutrients to the osteocytes in tribeculae? What kind of process is this?
Canaliculi provide nutrients to cells through diffusion.
What are some examples of osteogenesis throgh intramembranous ossification?
Forms flat bones of the skull, some facial bones, mandible, and clavicle.
What is encochondral ossification?
Bone growth within cartilage.
Turns fetal framwork of hyaline cartilage into bone.
Where are the ossification centers in endochondral ossification?
Primary ossification center in diaphysis, secondary ossification center in epiphysis.
What does interstitial and appositional growth mean?
Interstitial growth = length
Appositional growth = width
Describe interstitial growth at the epiphyseal plates.
1. Chondroblasts near epiphyseal plate multiply; epiphysis is pushed away from diaphysis.
2. Chondrocytes enlarge; matrix calcifies.
3. Chondrocytes die and disintegrate.
4. Remodeling by osteoclasts.
What are the different types of bone fractures?
Open or compound fractures
What is a pathologic fracture?
Disease weakens the bone. (breaking because of disease, e.g. osteoporosis)
What are the steps of bone repair?
1. Fracture hematoma forms (blood rushes in)
2. Fibrocartilage (soft) callus forms
3. Hard (bony) callus forms
4. Bone remodeled
What is osteomalacia?
Osteo = bone, malacia = soft
Called Rickets in children.
Leads to bowed legs
What is osteitis deformans?
Excessive osteoclast and osteoblast function.
Bone is unstable and immature.
Name the three types of cartilage. Where do we find each type? Which type is on the end of long bones?
• Hyaline cartilage: Costal cartilage, fetal skeleton, epiphyseal plate, articular cartilage, trachea
• Fibrocartilage: Pubic symphysis, menisci of the knee and intervertebral discs
• Elastic cartilage: Ears and epiglottis
Hyaline cartilage is found on the ends of long bones (articular cartilage).
The names of mature chondro/osteo cells end with the suffix ____. Immature (building cells) end in ____.
What is the function of red bone marrow? Yellow bone marrow?
Red bone marrow performs hematopoiesis or the production of blood cells. Yellow bone marrow stores energy in the form of fat.
What are the four structural classifications of bones? What type of bone is the ox coxa? Humerus? Rib? Metacarpal?
Long, short, flat and irregular; os coxa = irregular, humerus = long, rib = flat, metacarpal = long
Draw and label the canals of the osteon. Name the concentric rings and cavities containing osteocytes.
Concentric rings = concentric lamellae; cavities containing osteocytes = lacunae
What type of ossification forms the flat bones of the skull? Which begins with a hyaline model?
What is the difference between osteoporosis and osteomalacia?
Osteoporosis typically occurs in older adults and is characterized by bone that has become less dense and more porous. Osteomalacia typically occurs in children when bone becomes softer and more flexible due to calcium and vitamin D deficiencies.