Quiz 2 prep (muscles)

Question 1

What are three types of muscle tissue types?

Answer 1

1. Skeletal
2. Cardiac
3. Smooth

Question 2

What is a Muscle Fiber?

Answer 2

• An individual muscle fiber is a bundle of myofibrils

Question 3

What are 6 components of muscle structure?

Answer 3

1. A-bands
2. Sarcomere
3. z-line
4. I-band
5. H-zone
6. M-line

Question 4

What is an A-band?

Answer 4

• Anisotrophic band
• an-without, iso-same, trophic-property
• appearance is dependent on its orientation

Question 5

What is a Sarcomere?

Answer 5

• A contractile unit of Muscle
• contains arranged myofibrils
  
  • thin
  • thick

Question 6

What is a Z-line?

Answer 6

The disk/line inbetween the I bands. Appears as a seires of dark lines.

Question 7

What is an I-band?

Answer 7

• Zone of thin filaments that is not superimposed by thick filaments.
• Looks the same in every direction

Question 8

What is the H-zone?

Answer 8

• “brighter”
• lighter appearance under microscope
• sone of thick filaments , not superimposed by thin filaments.

Question 9

What are characteristics of Cardiac Muscle, where is it found?

Answer 9

• Branched
• has intercalated fibers
• striated
• involuntary
• Found in most of wall of the heart

Question 10

What are characteristics of skeletal muscle, where is it found?

Answer 10

• striated
• voluntary
• mostly attached to bones

Question 11

What are characteristic of smooth muscle, where is it found?

Answer 11

• nonstriated
• involuntary
• located in viscera

Question 12

Name 6 types of fascicle arrangement of muscle.

Answer 12

1. Unipennate
2. Bipennate
3. Multipennate
4. Spiral
5. Triangular
6. Circular

Question 13

List Muscle structure from innermost to outermost.

Answer 13

1. Muscle cell/ Myofibril
2. muscle fiber
   
   • bundle of myofibril
3. Endomysium
4. fascicle
   
   • bundle of muscle fiber
5. paramysium
6. skeletal muscle
   
   • bundle of fascicles
7. Epimysium
8. fascia
9. tendon
10. bone

Question 14

What are thin filaments of myofibril?

Answer 14

• Composed of Actin, tropomyosin, and troponin.
• have globular protein active sites that bind myosin heads

Question 15

What are thick filaments of myofibril?

Answer 15

Consist of myosin tails and heads

Question 16

What are the role of tropomyosin and troponin? Where are they found?

Answer 16

• FOund in thin filament
• Regulatory proteins.

Question 17

How does Muscle Contraction happen?

Answer 17

Uses Tropomyosin and troponin, regulatory proteins.

Troponin binds to Ca and causes tropomyosin to change shape and expose the actin binding sites. thick filament head ataches at actin binding site and a “power stroke (row)” happens.

Question 18

What are Type 1 muscle fibers?

Answer 18

• presence of oxygen binding protein, myoglobin.
• appear red
• suited for endurance
• small diameter
• slow to fatigue because they use oxidative metabolism to generate ATP
• “slow twitch muscle”

Question 19

What are Type 2 Muscle Fibers?

Answer 19

• Absence of Myoglobin and reliance on glycolytic enzymes.
• Efficient for short bursts of speed and power
• Use both oxidative metabolism and anaeobic metabolism
• “fast twitch”
• quick to fatigue