Unit 3 Test

Question 1

Small channels in the bone that transmit blood vessels from the periosteum into the bone and that communicate with the central (haversian) canals.

Answer 1

Perforating (Volkmann) canals

Question 2

Irregular latticework of think plates of spongy bone tissue

Answer 2

Trabeculae

Question 3

Define “ossification.”

Answer 3

Formation of bone

Question 4

The process of bone formation

Answer 4

Osteogenesis

Question 5

What is osteoid tissue?

Answer 5

Newly formed organic bone matrix before calcification.

Question 6

____ ____ is the process for the formation of many ____ bones in the fetus.

Answer 6

Intramembranous ossification is the process for the formation of many flat bones in the fetus.

Question 7

____ ossification is the formation of osseous tissue by the ____ of calcified cartilage.

Answer 7

Endochondral ossification is the formation of osseous tissue by the replacement of calcified cartilage.

Question 8

What is the basic structural unit of adult compact bone?

Answer 8

Osteon

Question 9

What structures are inside an osteon?

Answer 9

• Concentric osseous lamella (layers/tree rings)
• Central (haversian) canal
  
  • blood vessels
  • lymph vessels
  • nerves

Question 10

What is the name of the circular channel running longitudinally in the center of an osteon of mature compact bone containing blood & lymph vessels and nerves?

Answer 10

Central (Haversian) canal

Question 11

Lamellae are hard, calcified extracellular matrix in compact bone resembling ____ ____.

Answer 11

Lamellae are hard, calcified extracellular matrix in compact bone resembling tree rings.

Question 12

What is an osteoclast?

Answer 12

An osteoclast is a large, multinucleated cell that resorbs (destroys) bone matrix.

Question 13

What are the thin lines connecting the lamellae?

Answer 13

Canaliculi

Question 14

What are the small, hollow spaces in bones that contain osteocytes?

Answer 14

Lacunae

Question 15

What’s an osteocyte?

Answer 15

A mature bone cell

Question 16

What type of cell builds bone?

Answer 16

Osteoblasts

Question 17

A type of stem cell found in the inner layer of the periosteum that develops into osteoblasts

Answer 17

Osteogenic cells

Question 18

The thin membrane that lines the medullary cavity is known as ____.

Answer 18

Endosteum

Question 19

What’s the epiphyseal plate?

Answer 19

It’s a plate of hyaline cartilage at the junction of the diaphysis & epiphysis of a long bone, which provides for growth in length.

Question 20

What’s the growth plate?

Answer 20

Epiphyseal plate

Question 21

The ____ is a thick membrane that covers the entire surface of a bone except its articular cartilage.

Answer 21

The periosteum is a thick membrane that covers the entire surface of a bone except its articular cartilage.

Question 22

Where is the articular cartilage located?

Answer 22

@the epiphyses of movable joints

Question 23

What type of cartilage is articular cartilage?

Answer 23

Hyaline cartilage

Question 24

What part of a bone is the epiphysis?

Answer 24

Question 25

What part of a bone is the diaphysis?

Answer 25

Question 26

What type of bone is this?

Answer 26

Trabecular/spongy/cancellous

Question 27

\_\_\_ is lightweight bone tissue that makes up the interior of bones and contains spaces with red bone marrow.

Answer 27

**Trabecular bone** is lightweight bone tissue that makes up the interior of bones and contains spaces with red bone marrow.

Question 28

What is this part of long bones?

Answer 28

The medullary cavity

Question 29

What is the function of the medullary cavity?

Answer 29

Stores yellow bone marrow in adults

Question 30

Define compact bone

Answer 30

Compact bone forms the external portion of all bones and the bulk of the diaphysis of long bones; found immediately deep to the periosteum and superior to trabecular bone

Question 31

Define hemopoietic

Answer 31

formation of blood cells

Question 32

What forces bone to deposit minerals?

Answer 32

* Stress * mechanical stress * excercise

Question 33

What type of connective tissue comprises tendons?

Answer 33

Dense regular connective tissue

Question 34

What is the function of tendon?

Answer 34

Connects musle to bone

Question 35

What is the function of ligaments?

Answer 35

Connecting bone to bone

Question 36

Compare and contrast ligaments and tendons

Answer 36

* Compare * both are dense regular connective tissue * Contrast * tendons connect muscle to bone * ligaments connect bone to bone

Question 37

Define cartilage

Answer 37

Connective tissue consisting of chondrocytes in lacunae, embedded in a dense network of collagen and elastic fibers and an extracellular matrix of chondroitin sulfate.

Question 38

Which disorder results in bones that are inadequately mineralized, causing "soft bones," due to a lack of Vitamin D?

Answer 38

* Children * Rickets * Adults * Osteomalacia

Question 39

\_\_\_\_ ____ is secreted by the anterior ____ and stimulates metabolism and tissue growth.

Answer 39

**Growth Hormone (GH)** is secreted by the anterior **pituitary** and stimulates metabolism and tissue growth.

Question 40

What effects do anabolic steroids have on bone growth?

Answer 40

* bone growth stops * epiphyseal plate "closes" prematurely * abnormally short adult stature

Question 41

What effects are caused by low levels of sex hormones (estrogens and testosterone)?

Answer 41

* Estrogen * Increase in resorption and osteoporosis * Testosterone * Low bone mass

Question 42

The picture on the right depicts what condition?

Answer 42

Lordosis

Question 43

What condition is this?

Answer 43

Kyphosis

Question 44

Define osteoporosis.

Answer 44

Osteoporosis is an age-related disorder characterized by decreased bone mass and increased susceptability to fractures as a result of decreased levels of estrogen.

Question 45

How much of the body's PO₄^3- is in the skeleton?

Answer 45

85-90%

Question 46

The process involving bone formation and destruction in response to hormonal or mechanical stress is known as \_\_\_\_.

Answer 46

The process involving bone formation and destruction in response to hormonal or mechanical stress is known as **remodeling**.

Question 47

Where is PTH formed and released?

Answer 47

Parathyroid gland

Question 48

PTH release is a response to which condition?

Answer 48

Hypocalcemia

Question 49

What's the function of PTH?

Answer 49

* Raises blood Ca²⁺ level * increases intestinal absortion of Ca²⁺ * promotes kidney reabsorption of Ca²⁺ and excretion of PO₄^3-

Question 50

Which gland releases calcitonin?

Answer 50

Thyroid

Question 51

Releasing calcitonin is a response to which condition?

Answer 51

Hypercalcemia

Question 52

What is the function of calcitonin?

Answer 52

* lowers blood Ca²⁺ * inhibits resorption

Question 53

What is hypercalcemia?

Answer 53

Increased levels of blood Ca²⁺

Question 54

What is a decrease of Ca²⁺ levels in the blood?

Answer 54

hypocalcemia

Question 55

Compare and contrast hypocalcemia and hypercalcemia

Answer 55

Question 56

What is appositional growth?

Answer 56

Growth by the addition of new layers to the surface of those previously formed.

Question 57

At what is the arrow pointing?

Answer 57

the epiphyseal line, or the remnant of the epiphyseal plate

Question 58

What is interstitial growth?

Answer 58

tissue growth from a number of different centers within a nonrigid matrix

Question 59

C&C appositional vs interstitial growth.

Answer 59

Question 60

How much of the body's Ca is in the skeletal system?

Answer 60

~99%

Question 61

What is the function of osteoclasts?

Answer 61

Resorption - removal of osseous tissue

Question 62

A stone formed within various body parts is known as \_\_\_\_.

Answer 62

A stone formed within various body parts is known as a **calculus**.

Question 63

How much of bone consists of the mineral hydroxyapatite?

Answer 63

~65%

Question 64

Which part of long bones contains the gowth plate?

Answer 64

The **metaphysis** is the region of long bone between the diaphysis and epiphysis that contains the epiphyseal plate in a growing bone.

Question 65

What are the functions of the skeletal system?

Answer 65

1. support 2. protection 3. movement 4. electrolyte balance 5. acid-base balance 6. blood formation

Question 66

What are short bones?

Answer 66

Question 67

What are flat bones?

Answer 67

Question 68

What are irregular bones?

Answer 68

Question 69

What are long bones?

Answer 69

Question 70

What is the nutrient foramen?

Answer 70

An external opening for the entrance of blood vessels in a bone.

Question 71

What are Sharpey's fibers?

Answer 71

They connect the periosteum to the bone.

Question 72

What role does osteocalcin play?

Answer 72

Osteocalcin is secreted by osteoblasts and is implicated in mineralization & Ca²⁺ homeostasis

Question 73

What is mineralization?

Answer 73

Process of laying down minerals on bone matrix Ca₃(PO₄)₂

Question 74

The active form of Vitamin D is what?

Answer 74

Calcitriol

Question 75

The body will adapt to the loads/stresses acted upon it.

Answer 75

Wolff's Law