Anatomy Lecture Ch. 6 Pt.1

What is skeletal cartilage? 

highly resilient, molded cartilage tissue that consists primarily of water. 

True or False:

Skeletal Cartilage contains no blood vessels or nerves.

True

What is the Perichondrium?

Layer of dense connective tissues surrounding cartilage like a girdle.

What does Perichondrium help in?

helps cartilage resist outward expansion.

What is cartilage made up of?

Chondrocytes

What are chondrocytes?

Cells encased in small cavities (lacunae) within jelly-like extracellular matrix.

What are the 3 types of cartilage?

Hyaline, Elastic, Fibrocartilage

What is hyaline cartilage?

Provides support, flexibility, and resilience

True or False:

Hyaline cartilage does NOT contain collagen fibers only.

False

Where is hyaline cartilage seen?

Articular (joints), costal (ribs), respiratory (larynx), nasla cartilage (nose tip)

What is elastic cartilage?

similar to hyaline cartilage, but contains elastic fibers

Where can you find elastic cartilage?

in the external ear and epiglottis

What is fibrocartilage?

Thick collagen fibers which have great tensile strength.

Where can you find fibrocartilage?

Menisci of knee, vertebral discs

What are the 7 important functions of bones?

1. Support

2. Protection

3. Movement

4. Mineral and growth factor storage

5. Blood cell formation

6. Triglyceride (fat) storage

7. Hormone production

What does Support do?

For body and soft organs

What does Protection do?

Protect brain, spinal cord, and vital organs.

What does Movement do?

Levers for muscle action

What does Mineral and growth factor storage do?

Calcium and phosphorus, and growth factors reservoir

Where does hematopoiesis do?

occurs in red marrow cavities of certain bones

What is triglyceride (fat) storage?

Fat, used for an energy source, is stored in bone cavities

What is osteocalcin?

it is secreted by bones and helps to regulate insulin secretion, glucose levels, and metabolism

How many named bones are there in the human skeleton?

206

True or False:

Bones are divided into two groups based on location?

True

What are the two groups of bones?

1. Axial skeleton

2. Appendicular skeleton

What does the Axial skeleton consist of?

Long axis of body, skull, vertebral column, ribs

What does the Appendicular skeleton consist of?

bones of the upper/lower limbs, girdles attaching limbs to axial skeleton

Bones are classified into 1 of 4 shapes. What are they?

1. long bones

2. short bones

3. flat bones

4. irregular bones

Describe long bones:

Longer than they are wide

limb bones

Describe short bones:

cube-shaped bones (in wrist and ankles), they vary in size and number in different individuals 

Where do sesamoid bones form?

They form within tendons 

(EX: Patella)

Describe flat bones:

thin, flat, slightly curved

(EX: sternum, scapulae, ribs, most skull bones)

Describe Irregular bones:

complicated shapes

(EX: vertebrae and hip bones) 

What classification is a limb bone?

Long bones

What classification are wrists and ankle bones?

Short bones

What classification would a patella bone be?

Short bone

What classification would the sternum be?

Flat bone

What bone classification would the scapulae be?

Flat bone

What bone classification would the ribs be?

flat bones

What bone classification would most skull bones be?

Flat bone

What bone classification would the vertebrae be?

irregular bones

What bone classification would the hip bones be?

irregular bones

True or False:

Bones ARE organs because they contain different types of tissues.

True

True or False:

A Bone contains nervous tissue, cartilage, fibrous connective tissue, muscle cells, and epithelial cells in its blood vessels.

True

What are the 3 levels of structure for bones?

1. gross

2. microscopic

3. chemical

What is compact bone?

dense outer layer on bones that appear smooth and solid.

What is spongy bone?

made up of “honeycomb” of small-needle-like or flat pieces of bone called trabeculae.

True or false:

Open spaces between trabeculae ARE filled with red or yellow bone marrow.

True

True or false:

Spongy bone has a mesh of bony spines called trabeculae

True

True or false:

Compact bone does NOT look smooth and solid

False

(compact bone appears smooth and solid)

What does the structure of short, irregular, and flat bones consist of?

thin plates of spongy bone covered by compact bone 

What is another word for spongy bone?

diploe

True or False:

Compact bone IS sandwiched between connective tissue membranes.

True

What is the periosteum?

It covers the OUTSIDE portion of compact bone.

What is the Endosteum?

It covers the INSIDE portion of compact bone.

Where is bone marrow scattered throughout?

spongy bone

What does hyaline cartilage cover?

area of bone that is part of a movable joint.

What is the “shaft” and also forms the long axis of a long bone?

diaphysis

What is the end of a long bone called?

epiphyses

True or false:

The Epiphyses consists of compact bone externally and spongy bone internally

True

True or False:

Articular cartilage does NOT cover articular (joint) surfaces.

False

( articular cartilage does cover articular joint surfaces)

What is between the diaphysis and epiphysis?

Epiphyseal line

What occurs in epiphyseal plate?

bone growth

What are the 2 membranes?

1. periosteum

2. endosteum

What is the periosteum?

white, double-layered membrane that covers the EXTERNAL surfaces except joints.

What is the fibrous layer?

outer layer consisting of dense irregular connective tissue that consists of Sharpey’s fibers that secure bone to matrix. 

What is the Osteogenic layer?

inner layer abutting bone and contains primitive osteogenic stem cells.

True or False:

The periosteum contains many nerve fibers and blood vessels that continue on to the shaft through nutrient foramen openings. 

True

True or false:

The periosteum is NOT an anchoring point for tendons and ligaments.

False

What does the endosteum cover? 

it is a delicate connective tissue membrane that covers internal bone surace. 

True or false:

The endosteum covers trabeculae of spongy bone.

True

True or false:

The endosteum does NOT line canals that pass through compact bone.

FALSE

Does the endosteum contain osteogenic cells?

Yes, just like the periosteum they both can differentiate into other bone cells.

Where is Red marrow found?

within trabecular cavities of spongy bone and diploe of flat bones. such as sternum

True or False:

In newborns, medullary cavities and all spongy bone contain red marrow.

true

True or False:

In adults, red marrow is located in heads of femur and humerus.

true

True or false:

Yellow marrow can covert to red, if person becomes anemic.

true

What are bone markings?

sites of muscle, ligament, and tendon attachment on external surfaces.

Are bone markings involved in joint formation and conduits for blood vessels and nerves?

Yes

What are the 3 types of bone markings:

1. projection: outward bulge of bone

2. depression: bowel or groove-like cut-out that serves as passageways for nerves/vessels

3. opening: hole/canal in bone acts like passageways for nerves/vessels.

What are the 5 major cell types?

1. osteogenic cells

2. osteoblasts

3. osteocytes

4. bone-lining cells

5. osteoclasts

what are osteogenic cells?

mitotically active stem cells in periosteum and endosteum

when stimulated what do osteogenic cells become?

they differentiate into osteoblasts or bone-lining cells

what are osteoblasts

bone-forming cells that secrete unmineralized bone matrix called osteiod

what is made up of collagen and calcium-binding proteins

osteoid

true or false

collagen makes up 90% of bone protein

true

what are osteocytes

mature bone cells in lacunae that no longer divide

what do osteocytes maintain?

they maintain bone matrix and act as stress or strain sensors

what are osteoclasts?

cells that destroy bone

what are bone-lining cells?

flat cells on bone surfaces believed to also help maintain matrix (along with osteocytes)

periosteal cells

on external bone surface, lining cells are called

endosteal cells

on internal bone surfaces is called

what are osteoclasts 

giant, multinucleated cells that finction in bone resorption (breakdown of bone)

resorption bays

where are osteoclasts located at when active?

compact bone

What is also called a lamellar bone?

one of the 3 things a compact bone consists of

osten (haversian system)

one of the 3 things a compact bone consists of

canals and canaliculi

one of the 3 things a compact bone consists of

interstitial and circumferential lamellae

what is an osteon?

structural unit of compact bone