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Cell Pathology 2 (Histology) - 2016 > Muscle Diversity > Flashcards

Flashcards in Muscle Diversity Deck (27)
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1
Q

Which type of muscle is shown in the image?

A

Skeletal muscle fibers (longitudinal) - striated, syncytial, visible myofibers

2
Q

Which type of muscle is shown in the image?

A

Skeletal muscle fibers (cross-section) - multiple, peripheral nuclei

3
Q

Which layer of skeletal muscle makes up the outside layer?

A. Endomysium

B. Perimysium

C. Epimysium

D. None of these

A

C

4
Q

Which is true regarding innervation of skeletal muscle fibers?

A. Stimmulation produces contraction

B. Stimulating a muscle fiber causes shortening of the fiber

C. Only one synapse occurs per fiber

D. All of the above

A

D

5
Q

Actin and myosin are known as the:

A. Myofibers

B. Myofilaments

C. Myofibrils

A

B

6
Q

Which true regarding myosin heavy chains (MHC)?

A.

B.

C.

D.

A
7
Q

Which of the following is NOT a thick filament protein?

A. Myosin

B. C-Protein

C. M-Protein

D. Titin

E. Actin

A

E

8
Q

What component of the motor unit covers the binding site for actin?

A. Tropomyosin

B. Troponin C

C. Troponin I

D. Troponin T

E. None of these

A

A

9
Q

A ________ is a bundle of myofilaments in a sacroplasmic reticulum sheath.

A. Myofiber

B. Myofilament

C. Myofibril

A

C

10
Q

The image shown features what part of the skeletal muscle?

A

T-tubules (transverse tubules)

11
Q

Red muscle fibers:

A. are fast twitch

B. are flight muscles

C. have low fatigability

D. use glycolysis

A

C

12
Q

White muscle fibers:

A. are fast twitch

B. are postural muscles

C. use oxidative metabolism

D. fatigue slowly

A

A

13
Q

Which best describes the muscle fiber with the star in the image shown?

A. Fast twich

B. Glycolytic

C. Red muscle fibers

D. All of the above

A

C

14
Q

Which type of muscle fiber is shown in the image? Which two properties allow us to identify this type?

A

Cardiac muscle fiber - indicated by a) branching fibers and b) intercalated discs

15
Q

The darker patterns in the image displayed here represent:

A. Capillaries

B. Mitochondria

C. Myosin

D. Actin

A

B - very prevalent in cardiac muscle

16
Q

A fasciae adherens is to a cardiac muscle cell as an _______ is to an epithelial cell.

A. gap junction

B. desmosome

C. adherens junction

D. intercalated disk

A

C

17
Q

The arrow in this image is pointing to which component of the junctional complex in the cardiac muscle cell?

A. Intercalated disc

B. gap junction

C. desmosome

D. none of these

A

A

18
Q

Which is true regarding Ca2+ in muscle?

A. In cardiac muscle, around half of Ca2+ comes from extracellular space while in skeletal muscle, half of the Ca2+ comes from cytosol

B. In cardiac muscle, around half of Ca2+ comes from extracellular space while in skeletal muscle, most of the Ca2+ comes from cytosol

C. In both cardiac and skeletal muscle, around half of Ca2+ comes from extracellular space

D. In both cardiac and skeletal muscle, most of Ca2+ comes from the cytosol

A

B

19
Q

Which is true about the control of cardiac muscle?

A. Gap junctions are essential to functioning

B. Tight junctions are essential to functioning

C. All cells are innervated since the cardiac contraction is intrinsic

D. The heart contracts by recruiting motor units

A

A

20
Q

As the cardiac muscle contracts:

A. Both ACh and Norepinephrine decrease

B. ACh increases, Norepinephrine decreases

C. ACh decreases, Norepinephrine increases

D. Both ACh and Norepinephrine increase

A

C

21
Q

The image featured here displays which type of muscle?

A

Longitudinal section of smooth muscle

22
Q

In the smooth muscle, actin is anchored in __________.

A. intermediate filaments

B. mechanical junction coupling cells

C. dense bodies

D. thin filaments

A

C

23
Q

In the active state, smooth muscle filaments:

A. have light chains which are not phosphorylated

B. have heavy chains which are not phosphorylated

C. have heavy chains which are phosphorylated

D. have light chains which are phosphorylated

A

D

24
Q

The sarcoplasmic reticulum of smooth muscle has:

A. an extracellular source of Ca2+

B. an intracellular source of Ca2+

C. myofibrils

D. T-tubules

E. more than one of the above

A

A

25
Q

The smaller, dark spots (as indicated by the yellow circle) represent which component of smooth muscle?

A. Mitochondria

B. Dense bodies

C. Gap junctions

A

B

26
Q

Multi-unit smooth muscle is found in:

A. Uterus

B. Blood vessels

C. Respiratory bronchioles

D. More than one of the above

A

D - both B and C contain multi-unit smooth muscle

27
Q

Contraction of smooth muscle myosin requires:

A. Ca2+ removal

B. MLC phosphatase to cleave the phosphate

C. Ca2+ Calmodulin to activate the MLCK

D. Ca2+ Calmodulin to deactivate the MLCK

A

C