CH 3 Specific Tissue or Organ Repair

Question 1

What types of organs are composed of cells that cannot regenerate?

Answer 1

Heart, CNS, PNS cells

Question 2

Liver, epithelial cells of integumentrary and GI systems can replace missing tissue through?

Answer 2

Cell division (mitosis)

Question 3

What types of cells do not divide but can be induced to undergo mitosis?

Answer 3

Skeletal muscle cells and renal cells

Question 4

What depends on the type of cell (permanent, stable, labile), the cell’s ability to divide, the type of damage incurred (lethal, sublethal), and other factors discussed (nutrition, age, immunocompetency, vascular supply, presence of microorganisms leading to infection)?

Answer 4

Extent to which cells regenerate

Question 5

What can only occur if the parenchymal cells can undergo mitosis?

Answer 5

Regeneration

Question 6

When regeneration of parenchymal cells is not possible, what happens?

Answer 6

Inflammatory reaction becomes chronic

Question 7

What lung cells primarily produce surfactant?

Answer 7

Type II pneumocytes

Question 8

What must remain intact in the lung for regeneration to occur?

Answer 8

The basement membrane of the lung

Question 9

What occurs after lethal injury to alveolar cells (type I and II pneumocytes) of the lung while the basement membrane remains intact?

Answer 9

After phagocytic removal of necrotic cells, adjacent epithelial cells migrate onto remaining basement membrane and differentiate into type II pneumocytes.

Question 10

What type of lung cells permit gas exchange?

Answer 10

Type I pneumocytes

Question 11

For full lung function to occur, what must occur?

Answer 11

Some cells will differentiate into type I pneuomocytes from type II

Question 12

What occurs when the damage to the lung disrupts the basement membrane?

Answer 12

Healing must be achieved by repair that is characterized by fibrosis and scar formation

Question 13

What is an example of certain injurious agents that induce lung healing by forming scar tissue and leading to restrictive lung disease?

Answer 13

Inhalation of asbestos

Question 14

Finger-like projections that are responsible for nutrient absorption and the production of digestive enzymes?

Answer 14

Villi

Question 15

How do gut cells grow?

Answer 15

In a single file from the bottom up

Question 16

How often do gut cells pass out of the body?

Answer 16

5 days

Question 17

How long does it take for a complete turnover of all gut cells throughout the digestive tract?

Answer 17

3-4 weeks

Question 18

How long does a mildly to moderate impaired gut take to heal?

Answer 18

3-6 months

Question 19

How long does a severe intestinal injury take to heal?

Answer 19

12-18 months

Question 20

How much of all immune system function takes place in the gut?

Answer 20

Two-thirds

Question 21

How much serotonin function takes place in the gut?

Answer 21

90%

Question 22

What is needed to produce melatonin?

Answer 22

Serotonin

Question 23

What is an essential component for a good, restful sleep?

Answer 23

Melatonin

Question 24

A proper amount of circulating and functioning serotonin is needed to?

Answer 24

Stabilize mood

Question 25

What happens when a nerve is cut?

Answer 25

A peripheral portion rapidly undergoes a myelin degeneration and axonal fragmentation

Question 26

What process occurs when lipid debris is removed by macrophages mobilized from the surrounding tissues?

Answer 26

Wallerian Degeneration

Question 27

What happens within 24 hours of section of peripheral nerves?

Answer 27

New axonal sprouts from the central stump are observed with proliferation of Schwann cells from both central and peripheral stumps

Question 28

What type of muscle is composed of contractile and connective tissue?

Answer 28

Skeletal muscle

Question 29

Actin and myosin milafilaments make up what types of muscle fiber units?

Answer 29

Sarcomere

Question 30

What is the delicate sheath surrounding each individual myofiber?

Answer 30

Endomysium (basement membrane)

Question 31

What type of cells surround the skeletal muscle fibers and are important for tissue regeneration after injury?

Answer 31

Satellite cells

Question 32

Contusion, strain, laceration, and sprain are what types of injury?

Answer 32

Muscle injury

Question 33

Occurs when the muscle is subject to a sudden, heavy compressive force such as a direct blow to the muscle

Answer 33

Muscle contusion

Question 34

Occurs when the excessive tensile force leads to overtstraining of the myofibers

Answer 34

Muscle strain

Question 35

What injuries are about 90% of all muscle injuries?

Answer 35

Muscle contusion or strains

Question 36

Muscles that cross two-joint muscles are vulnerable to what type of injury due to simultaneously being affected by angular positions and velocities of adjacent joints?

Answer 36

Muscle stretch injury

Question 37

What type of muscle injury is more likely to occur during eccentric contraction when the muscle is lengthening because tension is greater than the muscle’s resistance to stretch; resultant forces are large

Answer 37

Muscle strains

Question 38

What is the most common site of a muscle strain injury?

Answer 38

Myotendinous junction

Question 39

What happens when the force of a stretch on a muscle is too great to be resisted by the contractile unit?

Answer 39

Resistance shifts from the contractile unit to the connective tissues

Question 40

What happens when a pathogenic stretch (passive, active) that is beyond the threshold length of the entire musculotendinous unit occurs?

Answer 40

Results in disruption at the myotendinous junction