Human Skeletal Anatomy and Osseous Tissue

Flashcards covering bone tissue properties, classification, anatomy of long and flat bones, cellular processes, fracture types, and specific structures of the axial and appendicular skeleton.

What two types of tissue primarily make up a bone?

Osseous tissue and a small part being cartilage.

What is a major physiological difference between osseous tissue and cartilage regarding healing?

Bone heals fast because it is highly vascularized and dynamic, whereas cartilage does not change based on stress.

How many bones do all humans have?

206.

According to what criteria are bones classified?

Shape.

Where are short bones found and what is their function?

Found in the Carpals and tarsal; they act as support for the hand and feet.

What is the primary function of flat bones?

They serve as attachment points for muscles.

How would the vertebral body specifically be described in terms of shape?

Cube bone.

What purpose do the transverse process and spinous process serve?

They jut out for muscles to attach to and pull on.

Which two Seisimoid bones are present in all people?

The patellae.

What are Wormian bones?

A special class of bones that closes sutures in the cranium.

What is the purpose of fontanelles?

To allow the head to fit through the birth canal.

What components of the matrix provide bone with hardness and flexibility?

Calcium Carbonate provides hardness; protein fibers provide flexibility.

Define the Epiphysis, Diaphysis, and Metaphysis of a long bone.

Epiphysis refers to the heads of bones; Diaphysis is the shaft; Metaphysis is where the diaphysis meets the epiphysis.

What feature is found at the metaphysis and what is it composed of?

The Epiphyseal plate, which is composed of cartilage.

What does the Epiphyseal plate become once growing stops?

The epiphyseal line.

What is the medullary cavity and what does it contain?

A hollow space in the diaphysis filled with Yellow marrow for the storage of fat.

What is found within the spongy bone of the epiphysis?

Blood vessels that condense and form red marrow, which is the site of hematopoiesis.

What type of cartilage covers the epiphysis and what is its function?

Articular cartilage (hyaline cartilage), which provides a smooth surface for articulation.

Contrast the Endosteum and Periosteum membranes.

The Endosteum is a thin, delicate membrane lining the medullary cavity used for repair and remodeling; the Periosteum is a fibrous outer membrane where blood vessels, nerves, and lymph enter.

What is the name for spongy bone found inside flat bones?

Diploe.

Define the surface markings: Fovea, Fossa, Foramen, and Meatus.

Fovea: small pit; Fossa: elongated depression; Foramen: an opening; Meatus: opening to a canal.

What is a Fissure?

A foramen that is not smooth or rounded.

Identify the four cell types in osseous tissue and their functions.

Osteogenic: dividing pluripotent stem cells; Osteoblasts: lay down bone matrix (osteoid); Osteocytes: mature cells in lacunae that maintain mineral concentration; Osteoclasts: responsible for bone absorption/resorption.

What is the origin of osteoclasts?

They differentiate from Macrophages.

What makes up the Calcium carbonate matrix?

Hydroxyapatite adhering to organic collagen fibers.

What are three tissues that require calcium to work?

All muscles, for muscle contraction (specifically actin and myosin interaction).

What is the function of Calcitonin?

It inhibits reabsorbtion by osteoclasts.

What is Tetany?

Involuntary contractions of skeletal muscle that happen if blood calcium levels dip.

Define an Osteon (Haversian system).

The bone unit consisting of concentric lamella surrounding a Haversian canal (central canal) which contains blood vessels, lymphatic vessels, and nerves.

How are osteocytes connected within an osteon?

By canaliculi.

Compare vertical and horizontal canals in compact bone.

Central canals run vertically; Perforating canals run horizontally.

What is the lattice work structure of spongy bone called?

Trabeculae.

Through what opening do blood and nerve supplies enter the bone?

Nutrient foramina.

What are the two pathways of ossification?

Intermembranous and endochondral ossification.

Define the following fracture types: Communited, Oblique, Transverse, Impacted, and Greenstick.

Communited: bone shatters; Oblique: breaks at an angle; Transverse: straight across; Impacted: break from falling from a great height; Greenstick: a hairline fracture that does not break the bone.

Categorize these bones as Axial or Appendicular: Ribs, Clavicle, Coccyx, Fibula, Radius, Calcaneus, Sphenoid.

Axial: Ribs, Coccyx, Sphenoid. Appendicular: Clavicle, Fibula, Radius, Calcaneus.

Which bones make up the nasal septum?

The Vomer (inferior) and the perpendicular plate of the ethmoid (superior).

Where do the coxal bones and the shoulder girdle articulate with the axial skeleton?

The coxal bones articulate at the Sacrum; the shoulder girdle articulates at the manubrium of the sternum via the clavicle.

What is the superior part of the ethmoid bone called?

Crista galli.

Which sutures connect the parietal bones to each other and to the temporal bones?

The Sagittal suture connects parietal bones; the Squamous suture connects the temporal bone to the parietal bones.

List the seven bones that make up the orbit.

Zygomatic, maxilla, lacrimal, ethmoid, sphenoid, frontal, and palatine.

Identify the four spinal curvatures and their anterior shapes.

Cervical (Convex), Thoracic (Concave), Lumbar (Convex), and Sacral (Concave).

What are the specialized names for C1 and C2, and what feature allows for rotation?

C1 is the Atlas; C2 is the Axis. The Dens (odontoid process) on C2 allows left and right motion.

Define Scoliosis and Kyphosis.

Scoliosis is lateral deviation of the column; Kyphosis is exaggerating the thoracic curvature.

What are the two parts of an intervertebral disc?

Nucleus pulposus (fluid part) and anulus fibrosus (fibrous part).

What unique features are found in cervical and thoracic vertebrae?

Cervical vertebrae have transverse foramen (for vertebral arteries); Thoracic vertebrae have superior and inferior costal facets for ribs.