Skeletal System

Question 1

What are the primary functions of long bones?

Answer 1

Support and movement

Long bones are crucial for supporting the body and facilitating movement due to their structure.

Question 2

What are the characteristics of short bones?

Answer 2

Roundish or cube-shaped; little to no role in movement

Short bones include carpals and tarsals.

Question 3

What type of bones are scapulae and sternum classified as?

Answer 3

Flat bones

Flat bones are suited for protection and muscle attachment.

Question 4

What defines irregular bones?

Answer 4

Complex shapes that do not fit other classifications

Examples include many facial bones.

Question 5

What are sesamoid bones?

Answer 5

Bones embedded in tendons, such as the kneecap

They help manage mechanical stress.

Question 6

What is the primary structure of compact bone?

Answer 6

Cylindrical structures called osteons

Osteons are also known as Haversian systems.

Question 7

What does the Haversian canal contain?

Answer 7

Nerve fibers and blood vessels

The Haversian canal is central to each osteon.

Question 8

What connects lacunae in compact bone?

Answer 8

Canaliculi

Canaliculi allow for nutrient and waste exchange between osteocytes.

Question 9

What is spongy bone primarily composed of?

Answer 9

Interconnected plates called trabeculae

Spongy bone contains red bone marrow which produces blood cells.

Question 10

What is the inorganic component of bone’s extracellular matrix?

Answer 10

Calcium phosphate (hydroxyapatite)

It comprises about 2/3 of the bone matrix.

Question 11

What role do osteoblasts play in bone formation?

Answer 11

They take calcium from the blood and produce the bone matrix

Osteoblasts eventually become osteocytes when encased in matrix.

Question 12

What are the three types of bone cells?

Answer 12

• Osteoblasts
• Osteocytes
• Osteoclasts

Each cell type has a unique function in bone health and maintenance.

Question 13

What is the function of osteoclasts?

Answer 13

Break down bone and return calcium to the blood

Osteoclasts are large multinucleate cells formed from monocytes.

Question 14

How are joints classified?

Answer 14

According to structure and function

Structure refers to the material holding the joint, while function refers to the range of motion.

Question 15

What type of joint is a suture?

Answer 15

Fibrous; immovable

Sutures are found in the skull.

Question 16

What type of cartilage is found in a synchondrosis joint?

Answer 16

Hyaline cartilage

Synchondrosis joints are nearly immovable.

Question 17

What is an example of a slightly movable joint?

Answer 17

Pubic symphysis

Pubic symphysis is classified as a cartilaginous joint.

Question 18

What type of joint is characterized by a joint cavity filled with synovial fluid?

Answer 18

Synovial joint

This is the most common type of joint.

Question 19

What type of joint allows rotation, such as the atlantonxial joint?

Answer 19

Pivot joint

Question 20

What type of joint allows movement in one plane, such as the knee?

Answer 20

Hinge joint

Question 21

What type of joint allows pivoting in two planes and axial rotation, exemplified by the first metacarpal/trapezium?

Answer 21

Saddle joint

Question 22

What type of joint allows sliding movements, as seen in carpals?

Answer 22

Gliding joint

Question 23

What type of joint allows pivoting in two planes but no axial rotation?

Answer 23

Condyloid joint

Question 24

What type of joint has the highest range of motion, as seen in the hip?

Answer 24

Ball and socket joint

Question 25

What is the term for immovable joints?

Answer 25

Synarthrosis

Question 26

What type of joint allows slight range of motion?

Answer 26

Amphiarthrosis

Question 27

What type of joint moves freely and is always synovial?

Answer 27

Diarthrosis

Question 28

Give an example of a synarthrosis joint.

Answer 28

Skull sutures, teeth/mandiol

Question 29

Give an example of an amphiarthrosis joint.

Answer 29

Intervertebral discs, distal tibiofibular joint

Question 30

Give an example of a diarthrosis joint.

Answer 30

Wrist, knee, shoulder

Question 31

What is one function of the skeletal system related to structural support?

Answer 31

Provides a framework for the body

Question 32

How does the skeletal system protect vital organs?

Answer 32

The skull encloses the brain, the vertebrae surround the spinal cord, and the thoracic cage protects the heart and lungs.

Question 33

What is the primary role of bones in the skeletal system?

Answer 33

Support the weight of the body and provide shape

Question 34

What cells remove calcium from the blood and deposit it into the bone?

Answer 34

Osteoblasts

Question 35

What is the term for a bone fracture that does not puncture the skin?

Answer 35

Closed fracture

Question 36

What type of fracture occurs when the bone breaks and punctures the skin?

Answer 36

Open fracture

Question 37

What is a comminuted fracture?

Answer 37

When the bone breaks in multiple areas

Question 38

What characterizes a greenstick fracture?

Answer 38

Part of the bone bends but does not fully break

Question 39

What is a spiral fracture?

Answer 39

When the bone is twisted apart

Question 40

What type of fracture occurs at an angle caused by an outside force?

Answer 40

Oblique fracture

Question 41

What is a transverse fracture?

Answer 41

When the fracture is perpendicular to the long axis of the bone

Question 42

What is a pathological fracture?

Answer 42

Caused by disease making the bone weak

Question 43

What is cartilage?

Answer 43

A connective tissue with a flexible matrix

Question 44

What are the immature cartilage cells that secrete the matrix called?

Answer 44

Chondroblasts

Question 45

What do chondroblasts mature into?

Answer 45

Chondrocytes

Question 46

What is the role of collagen in cartilage?

Answer 46

Provides structure and support

Question 47

What are the three types of cartilage?

Answer 47

Hyaline, elastic, and fibrocartilage ## Footnote Each type of cartilage has distinct structural and functional properties.

Question 48

What is the primary function of hyaline cartilage?

Answer 48

Provides support and flexibility ## Footnote It is found in articular surfaces and respiratory structures.

Question 49

What distinguishes elastic cartilage from other types?

Answer 49

Presence of elastic fibers ## Footnote This allows it to maintain shape while being flexible.

Question 50

Where is fibrocartilage typically found?

Answer 50

Jaw, knee, and between vertebrae ## Footnote Its thick collagen fibers allow it to withstand compressive forces.

Question 51

What is the role of ligaments?

Answer 51

Connect bones to bones and stabilize joints ## Footnote They are composed of dense connective tissue.

Question 52

What do tendons connect?

Answer 52

Muscles to bones ## Footnote Tendons facilitate movement and are tougher than ligaments.

Question 53

How are the fibers in tendons and ligaments different?

Answer 53

Tendons have more densely packed fibers ## Footnote This gives tendons greater strength compared to ligaments.

Question 54

What protein contributes to the yellowish color of certain ligaments?

Answer 54

Elastin ## Footnote Elastin provides elasticity to ligaments.

Question 55

Which hormone is known as calcitriol?

Answer 55

1,25-hydroxyvitamin D ## Footnote It is produced by the kidneys and regulates calcium levels.

Question 56

What effect does calcitriol have on calcium levels?

Answer 56

Promotes absorption of dietary calcium in the intestines ## Footnote This increases blood calcium levels.

Question 57

What is the function of calcitonin?

Answer 57

Inhibits osteoclast activity and stimulates osteoblast activity ## Footnote It is secreted when blood calcium levels are high.

Question 58

What does parathyroid hormone (PTH) do?

Answer 58

Increases quantity and activity of osteoclasts ## Footnote It is secreted when blood calcium levels are low.

Question 59

Fill in the blank: The _____ connect bones to bones.

Answer 59

ligaments

Question 60

True or False: Tendons are more elastic than ligaments.

Answer 60

False ## Footnote Tendons are tougher, while ligaments are more elastic.